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How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-16T17:02:31Z

Belix :

= Chapter 15 - Comprendre le pH de la maische =

== De quelle type d'eau j'ai besoin? ==

"De quelle type d'eau ai je besoin pour brasser tout-grain?" (vous demandez vous) Normalement, l'eau devrait etre d'une durete moderee et d'une aclinite de basse a moderee, mais ca depend ... "Qu'est ce que signifie ces termes? De quoi cela depend?" "Ou puis je obtenir ce type d'eau?" "A quelle eau ressemble mon eau?" ''What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?" '' 

Ce chapitre vous permettra de repondre a ces questions. Les reponses vont dependre du type de biere que vous voulez brasser et the profil mineral de l'eau que vous allez utiliser.

''This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.''

 

Le terme durete se refere au taux d'ions calcium et magnesium cintenu dans l'eau. Une eau dure va communement produire des depots dans les tuyaux. La durete de l'eau est liee pour une grande partie a l'acalinite de l'eau. Une eau alcaline est riche en bicarbonates. Une eau tres alcalines conduira le pH de votre maische plus eleve qu'il serait normalement. L'utilisation de malt fonce pourra contre-balance l'alcalinite de l'eau pour obtenir un pH adequat de votre maische, et ce principe va etre explorer dans ce chapite.

''The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.''

 

== 15.1 Reading a Water Report ==

Pour comprendre votre eau, vous avez besoin d'une copie de l'analyse de l'eau de votre reseau. Prenez contact avec votre mairie ou avec la societe de distribution et demandez leur une copie, generalement ils vous en enverrins une gratuitement. Un example pour la ville de Los Angeles est montre dans la Table 12. Les rapports d'analyse d'eau sont principalement oriente par la legislation sur la qualite de l'eau potable et axes sur les poluants comme les pesticides, les bacteries ou les metaux lourds. En tant que brasseur, nous nous interesserons a partie concernant les mineraux qui infulencent le gout et le pH. 

''To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. ''

Il y a plusieurs ions a prendre en considerartion quand il s'agit d'evaluer votre eau de brassage. The principaux ions sont le Calcium (Ca+2), le Magnesium (Mg+2), les carbonates (HCO3-1), et les sulfates (SO4-2). le sodium (Na+1), le chore (Cl-1), et les sulfates (SO4-2) peuvent influencer le gout de l'eau et de la biere, mais eux n'affecte pas le pH de votre maiche <strike>(NDT: j'ai enleve le comme les autres eu egard aux sulfates qui sont dans les deux </strike>). la concenration en ions de l'eau est generalement mesuree an partie par million (ppm), ce qui est correspond a 1 mg de la substance par litre d'eau (mg/l). Vous trouverez la description des ions a la suite de la table ci-dessous.

''There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.''

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Niveau recommande NS =  pas de standard defini ND = Pas detecte 

'''''*'''= Recommended Level NS = No Standard ND = Not Detected''

'''Calcium (Ca+2)'''

Poids atomique = 40.0

Poids equivalent = 20.0

Tolerance pour le brassage = 50 a 150 ppm

Le calcium est le principal ion derterminant la durete de l'eau et a une charge +2. Tout comme il l'est pour notre corps, le calcium est necessaire a beaucoup de levures, d'enzymes, de reaction proteinique, aussi bien lors de l'empatage que de l'ebulition. Il favorise la transparence, le gout, et la stabilite de biere finie. L'addition de Calcium peut etre necessaire pour assurer une activite suffisantes des enzymes lors de brassage avec une eau faible en calcium. Le calcium qui est combine au bicarbonate est aussi connue comme la "durete temporaire ou carbonatee". La durete temporaire peut etre supprimer par ebulition (voir bicarbonates). Le calcium qui subsite apres que l'on est supprime la durete tempraire est appele durete permanente

 Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Poids atomique = 24,3 Masse équivalente = 12.1 Domaine de brassage : de 10 a 30 ppm Cet ion agit de la manière que le calcium dans l’eau, mais avec moins d’efficacité. Il contribue lui aussi a la dureté de l’eau. Le Magnésium est un nutriment important des levures dans de faible quantité (10-20 ppm), mais des niveaux supérieurs à 50 ppm tendent a donner gout aigre-amer à la bière. Des niveaux supérieur à 125 ppm ont des effets laxatifs et diurétiques. 

''Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.''

'''Bicarbonate (HCO3-1) ''' Poids moléculaire = 61.0 Masse équivalente = 61 Niveaux pour le brassage = de 0 à 50 ppm pour les bières blondes, de 50 à 150 ppm pour les bières ambrées, de 125 à 250 pour les bières brunes, foncées. Les ions de la famille des carbonates sont très importants dans l’évaluation d’une eau de brassage. Le carbonate (CO3-2), est un ion alcalin, qui augmente le pH, et neutralise l’acidité des malts fonces. Son cousin, le bicarbonate (HCO3-1), a un pouvoir tampon divise par deux, mais est dominant dans les caractéristiques chimiques de l’eau de brassage car c’est la forme principale de carbonates dans les eaux ayant un pH inferieur à 8.4. Le carbonate, lui, représente généralement moins de 1% du total des carbonate/bicarbonate/acide carbonique présents dans les eaux avec un pH inferieur à 8.4. Il existe deux méthodes que les brasseurs peuvent utiliser pour réduire la concentration a un niveau de 50 a 150 ppm approprie pour la plupart de ale blonde, voir même a des niveaux inferieurs pour des lagers comme les pilseners. Ces méthodes sont l’ébullition et la dilution. 

 

''Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.''

Les carbonates peuvent être précipités sous forme de carbonate de calcium (CaCO3) par aération et ébullition par le biais de la réaction suivante : 

2 HCO3-1 + CA+2 + O2 (gazeux) --> CacO3 + H2O + CO2 (gazeux) 

Dans cette réaction l’oxygène provenant de l’aération agit comme un catalyseur and la chaleur due à l’ébullition empêche la re-dissolution du CO2 produit qui pourrait avoir lieu sous forme d’acide carbonique. 

''Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:''

'' 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas''

'' where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.''

La dilution est la méthode la plus simple pour produire une eau faiblement carbonatée. Utiliser de l’eau distillée que vous vous procurer facilement (Elle est souvent utilisée pour les fers à repasser à vapeur) dans une proportion de 1 pou 1, et vous réduirez ainsi par deux le taux de carbonates, vous obtiendrez cependant une légère différence due à des réactions tampons.

''Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.''

'''Sulfate (SO4-2)''' Poids moléculaire = 96.0 Masse équivalente = 48 Niveaux recommandes pour le brassage = 50 a 150 ppm pour les bières normalement houblonnées (amères), et de 150 a 350 pour les bières fortement houblonnées (fortement amères). 

''Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers ''

L’ion sulfate se combine aussi avec le Calcium ou le Magnésium et contribue a la dureté permanente. Il accentue l’amertume, produisant un effet plus sec de l’amertume, plus pétillant/tranchant. A des concentrations supérieures a 400ppm, il me conduire l’amertume a un caractère astringent et désagréable, et à des concentrations supérieures a 750 ppm il cause des diarrhées. Le sulfate a seulement un pouvoir faiblement alcalin et ne contribue par a l’alcalinité globale de l’eau.

''The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.''

'''Sodium (Na+1) ''' Poids atomique = 22.9. Masse équivalente = 22.9. Niveaux recommandes pour le brassage = de 0 a 150 ppm.

''Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. ''

Le sodium peut être présent a des concentrations très importantes, particulièrement si vous utilisez adoucisseur a base de sels (cad par échangeur d’ions) a la maison. En général vous ne devez jamais utiliser d’eau adoucie pour brasser. Vous aurez en effet surement besoin du Calcium qui sera remplace, et vous n’aurez clairement pas besoin des niveaux de sodium élevés qui seront produit. A des niveaux de 70 à 150 ppm il contribue à arrondir le gout de la bière, et accentue le coté doux du malt. Mais au dessus de 200ppm la bière va commencer à avoir un gout sale. La combinaison de sodium avec une forte concentration d’ions sulfate va génère une amertume très agressive. Ainsi il convient de tenir la concentration d’au moins un des ces ions a des niveaux aussi pas que possible, et de préférence celui du sodium.

Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chlorure (Cl-1)''' Poids atomique = 35.4 Masse équivalente = 35.4 Niveaux recommandes pour le brassage = De 0 a 250 ppm 

''Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm.''

L’ion chlore contribue au gout et la plénitude gustative d’une bière. Des concentrations supérieures a 300pm (dans des eaux fortement chlorées, ou résultant de résidus de désinfectant javellisé) peut conduire a des gouts médicamenteux du aux composes chlorophenol.

'' The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.''

'''Durete de l’eau, Alcilinite et milliEquivalence'''

La dureté et l’alcalinité de l’eau sont souvent exprimées comme « CaCO3 ». La dureté se référant à la concentration de cation, et l’alcalinité a celles des anions cad bicarbonate. Si l’analyse de votre eau ne spécifie pas les niveaux d’ion bicarbonate, ni l’alcalinité ou les dosages de CaCO3, pour vous donner une idee du pouvoir tampon de votre eau, vous aurez besoin de téléphoner les département gérant les eaux et demander à parler a un de leurs ingénieurs. Ils disposeront de cette information.

''Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.''

Le Calcium, et a un niveau moins important le Magnésium se combinent avec les bicarbonates pour formes du calcaire qui est très peu soluble dans une eau à pH neutre (7.0). La concentration totale de ces deux ions dans l’eau est appelée dureté et est le plus décelable aux dépôts calcaires dans la tuyauterie. La dureté de l’eau est souvent nommée dans les analyses municipales de l’eau comme dureté « CaCo3 » et est égale a la somme des concentrations en milliEquivalent (mEq/l) multiplie par 50 (la masse équivalente du CaCO3). Un équivalent est une mole d’un ion avec une charge +1 ou -1. La Masse équivalente du Ca+2 est la moitie de son poids atomique de 40 cad 20. Ainsi si vous divisez la concentration en ppm ou en mg/l du Ca+2 par 20 vous obtenez le nombre de milliEquivalent par litre de ca+2. En additionnant le nombre de milliequivalent de Calcium et de Magnésium puis en multipliant par 50 vous obtenez la dureté en milliEquivalent par litre de CaCO3.

''Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.''

(CA (ppm)/20 + mg(ppm)/12.1) x 50 = La dureté totale sous forme CaCO3.

''(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3''

Ces operations sont resumees dans la table suivante:

''These operations are summarized in the following table.''

Table 13 - Table de conversion de la concentration des ions.

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 '''Ph de l’eau ''' 

Vous devez penser que le pH de l’eau est important mais en fait il ne l’est pas. C’est le pH de la maiche qui est important. Et cette valeur dépend des tous ions présents dont nous avons déjà discuté. En fait, la concentration des ions n’est a prendre en considération telle quelle, et ce tant que l’eau n’est pas mélangée avec l’ensemble des grains, c’est le pH de ce mélange (NDT la maiche) qui doit être déterminé, et c’est ce pH qui affectera l’activité enzymatique lors de l’empattage ainsi que le niveau d’extraction des tannins astringent de l’enveloppe des grains.

''You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks.''

  De nombreux brasseurs se sont trompes en essayant de modifier le pH de leur eau avec des sels et des acides pour obtenir le pH désiré pour la maiche avant d’ajouter les malts. Vous pouvez le faire si vous avez suffisamment d’expérience avec une recette particulière qui vous permet de déterminer le pH résultant ; mais c’est un peu comme mettre la charrue avant les bœufs. Il est préférable de commencer l’empattage, vérifier le pH avec un papier pH et ensuite faire les ajustements que vous jugerez nécessaire pour obtenir le pH désiré. La plupart du temps ces ajustements ne seront pas nécessaires.

''Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.''

Cependant, beaucoup de personnes n’aiment pas faire confiance a la chance ou procéder par essai successifs en mesurant le pH de la maiche avec un papier pH et ajoutant des sels pour obtenir le bon PH. Il estime un moyen d’estimer le pH de votre maiche avant de commencer l’empattage et cette méthode sera développée dans la section suivante, mais d’abord voyons comment les grains affectent le pH de la maiche.

''However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.''

== 15.2 Equilibrage des malts et des minéraux ==

Si vous brassez en n'utilisant que du malt blond de base avec de l'eau distillée, vous obtiendrez habituellement une maishe avec un pH entre 5.7-5.8. (Rappelez-vous, que la plage idéale est un pH de 5.1-5.5). L'adjonction de malts spéciaux à l'acidité naturelle (par exemple le caramel, chocolat, ou noir) va avoir un effet important sur le pH de la maishe. Ainsi l'utilisation d'un malt cristal foncé ou grillé, à hauteur de 20% du grain, réduira souvent le pH d'une demi-unité (.5 pH). En utilisant de l'eau distillée et 100% de malt caramel on obtiendra normalement une maishe avec un pH de 4.5-4.8, avec du malt chocolat un ph de 4.3-4.5, et avec du malt noir un pH de 4.0-4.2. De son coté la composition de l'eau va elle influencer ou compenser l'effet que pourrait avoir ces malts spéciaux sur le pH de la maishe. La meilleure manière d'expliquer le phénomène est de décrire deux des bières les plus célèbres au monde et leurs eaux de brassage.La région de Pilsen en République Tchèque est le berceau de la bière de type Pilsener. La Pils est une bière blonde allemande dorée, sèche et limpide avec un goût de houblon particulier. L'eau de Pilsen est très douce, exempte de la plupart des sels minéraux et très pauvre en bicarbonates. Les brasseurs avaient pris l'habitude d'utiliser un acidifiant pour réduire le pH de la maishe, à base uniquement de malts blond de pilsen, à 5.1 - 5.5. 

 ''When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.''

Table 14 - Influence du profil de l'eau locale. 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

Extrait de "American Handy Book", 2:790, Wahl-Henius, 1902

L'autre bière à considérer est la Guinness, la célèbre bière Irlandaise. L'eau d'Irlande est riche en bicarbonates (HCO3-1), et a une quantité considérable de calcium mais pas suffisament pour équilibrer le bicarbonate. Ceci a comme conséquence une eau dure et alkaline avec une forte capacité de dosage. L'alcalinité élevée de l'eau rend difficile la production de bière blondes sans une amertume prononcée. En effet l'eau utilisée ne permet pas au pH de la maishe a base de malt, de baisser suffisamment pour atteindre la plage cible de ph de 5 - 5.8. Ce pH élevé induisant l'extraction élevé de composés phénoliques et de tanins amers provenant de l’enveloppe du grain. Un pH inférieur, (5.2-5.5) optimal pour une maishe, empêche normalement l’apparition de ces composés dans le produit final. Mais alors comment cette région du monde peut-elle être renommée pour produire les bières foncées exceptionnelles? La raison est en fait le malt foncé lui-même. En effet les malts noirs utilisés, fortement grillés, conduisaient naturellement Guinness à augmenter l'acidité de la maishe. L'acidité de ces malts neutralisant le pH élevé de l'eau, le pH de la maishe s’abaisse naturellement pour atteindre la plage de pH optimale.

''The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.''

Ainsi une bonne bière foncée ne pourrait pas être brassée dans la région de Pilsen, et des bonnes bières blondes légères allemandes dans la région de Dublin sans l'adjonction rigoureuse de sels minéraux appropries.Avant que vous brassiez votre première bière en tout-grain, vous devez obtenir la fiche d’analyse de votre eau de brassage et vérifier le profil minérale pour établir quels styles de bières en tireront avantage. L’utilisation de malts grilles comme du le caramel, chocolat, ou le Noir, ou de malt toaste comme le Munich ou le Vienne, sera fructueuse dans des régions ou l’eau est alcaline (cad, un pH supérieur a 7.5 et un niveau de carbonates supérieur a 200 ppm) et produiront des conditions idéales pour le brassage. Si vous vivez dans une région ou l’eau est très douce (comme Pilsen), alors vous pourrez ajouter des sels a votre eau de brassage et de rinçage pour obtenir le pH desire. Les deux sections suivantes de ce chapitre, Alcalinité résiduelle et pH de votre maiche, et utilisation des sels pour ajuster votre eau de brassage, vous aiderons dans cette démarche.

''The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.''

La table suivante liste un certain de style classique de bières ainsi que le profil de l’eau de la région ou elles sont brassées. En examinant la ville et le type de bières brassées, vous pourrez apprécier comment la chimie du malt et celle de l’eau interagissent. La description de la région et des styles de bière sont données ci-dessous :

''The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.''

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Style de biere 
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

Pilsen -

La faible dureté de l’eau et de son alcalinité permettre d’obtenir le pH désiré uniquement avec des malts de base, obtenant ainsi la douce saveur du pain frais. The manque de sulfate attenue l’amertume du houblon ce qui permet de ne pas dénaturer la douceur du caractère malté ; l’arome d’un houblon noble y est sublime.

''The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.''

Dortmund -

Une autre ville célèbre pour ces lagers pales, les Dormunt export ont un caractère moins houblonné que les pilsner, avec un caractère malte moins prononce dut a des teneurs en minéraux élevées. L’équilibre des minéraux est relativement similaire a celui de Vienne, mais la bière a plus de corps, plus sèche et plus pale.

''Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.''

Vienne -

L’eau de cette ville est très similaire a celle de dormant, mais manqué de calcium pour contre balancer les carbonates, et manque aussi de sodium et de chlore pour le gout. Les tentatives pour imiter les Dormunt Export furent des échecs cuisants jusqu'à ce que le pourcentage de malt toaste soit augmente pour équilibrer les brassins, ce qui donna naissance a cette fameuse bière rousse de Vienne.

''The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.''

Munich -

 Bien que d’un profil modéré en ce qui concerne la plupart des minéraux, l’alcalinité provenant des carbonates est élevée. Les aromes doux des dunkels, bocks ou autres oktoberfest de la région mette en avant le succès de l’utilisation de malts fonce pour contre balance les carbonates et acidifie la maiche. Le taux relativement bas de sulfate confère une amertume du houblon moins prononcée mettant en valeur les aromes de malt.

''Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.''

Londres -

Le taux de carbonate le plus élevé oblige l’utilisation de malt fonces pour equilibrer la maiche, mais le chlorure et le niveau eleve de sodium permetent d’adoucir les aromes, dont les resultats sous forme de porter fonces et de pale ale cuivrees sont bien connus.

''The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.''

Edinburgh -

Pensez aux brumeuses soirées écossaises et pensez aux robustes Scottish Ale – avec des reflets d’un rouge profond, des aromes doux de malt et d’agréable aromes de houblon en fin de bouche. L’eau est similaire a celle de Londres mais un peu moins carbonatée et mois de sulfate, se traduisant par une bière qui peut se permettre un corps plus malte avec un utilisation moins prononcée de houblons pour équilibrer ces bières.

''Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.''

Burton-on-Trent -

 Comparée a Londres, le calcium et le sulfate est remarquablement élevé, mais la dureté de l’eau et son alcalinité sont équivalent a ceux de pilsen. Le taux élevé de sulfate et le faible taux de sodium produisent une amertume franche mais pas trop prononcée. Comparées aux ales de Londres, celles de Burton sont plus pale, mais plus amères, bien que l’amertume soit atténuée par un taux d’alcool plus élevé et la corpulence de ces ales.

''Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.''

Dublin -

Fameuse pour ces Stout, Dublin à le taux de bicarbonate le plus élevé de toutes les iles britanniques, et l’Irlande l’utilise pour faire les bières les plus foncées et les plus maltées du monde. Le faible taux de sodium, de chlorure, et de sulfate contribue a une franche amertume du houblon pour équilibrer le cote très malté.

''Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.''

== 15.3 Alcalinité résiduelle et pH de la maiche ==

 Avant que vous ne commenciez votre premier brassage, vous voudrez probablement vous assurez qu’il se déroule bien. Beaucoup de personnes souhaitent brasser un Stout fonce ou bien une pilsner légère pour leur première expérience, mais ces styles très fonces ou très pales nécessitent une eau de brassage avec un profil bien défini pour obtenir un pH désiré. Alors qu’il n’existe aucun moyen infaillible de prédire le pH exact, il existe des méthodes empiriques and des formules qui peuvent vous y aider, tout comme les calculs d’IBU du houblon. Pour estimer le pH d’une maiche composée uniquement de malt de base, vous aurez besoins de connaître vos taux de calcium, magnésium, et votre alcalinité en vous aidant du rapport d’analyse de votre eau. Malheureusement, vous voudrez rarement brasser une biere en utilisant uniquement que des malts de base.

''Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.''

Pour estimer le pH de votre recette, vous aurez besoin du taux de Calcium, Magnésium, et de l’alcalinité de votre eau mais aussi de la couleur approximative de la bière que vous allez tenter de faire.

''To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.''

Historique: En 1953, P. Kohlbach a détermine que 3.5 Equivalents Calcium réagisse a la phytin du malt pour libérer un équivalent d’ions hydrogène qui pouvait neutraliser 1 équivalent d’alcalinité de l’eau. Le Magnésium, l’autre ion associe a la dureté de l’eau, agit lui aussi mais une moindre mesure, ainsi 7 équivalents sont nécessaire pour neutraliser 1 équivalent d’alcalinité. L’alcalinité qui n’est pas neutralise est appelée alcalinité permanente (RA Residual Alkalinity en Anglais). Base sur le volume, ceci peut être exprime par la formule suivante :

 

''In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: ''

mEq/L RA = mEq/L d’alcalinité – [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] ou mEq/L correspond a milliEquivalent par litre. 

mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

Cette alcalinité permanente conduira une maiche ne contenant que des malts de bases à avoir un pH supérieur a celui désire (cad > 6.0), ce qui conduira a une extraction de tanins, etc. Pour contrecarrer l’alcalinité permanente, les brasseurs ayant une eau alcaline comme celle de Dublin devront ajouter des malts grilles qui ont une acidité naturelle qui permettra au pH de la maiche de descendre au niveau désiré (5.2-5.6). Pour vous aider a déterminer votre alcalinité permanente, et déterminer ce que vous obtiendriez avec une maiche ne contenant que des malts de base, j’ai réuni toutes les informations nécessaire sur le graphique suivant, qui vous permettra de lire directement le pH d’une maiche ne contenant que des malts de base après avoir reporte vos niveau de calcium, Magnésium, et d’alcalinité. Pour utiliser le graphique suivant, vous devez pointer vos niveaux de Calcium, Magnésium pour déterminer une dureté « effective », puis tracer une ligne depuis cette valeur vers votre valeur d’alcalinité pour déterminer votre alcalinité résiduelle et approximer le pH. La dureté effective n’est pas la même que la dureté totale en CaCO3 que vous pourrez trouver sur le rapport d’analyse de votre eau, c’est un calcul de l’effet que le calcium et le magnésium ont sur l’alcalinité.

''This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.''

Apres la détermination de votre alcalinité permanente et le pH prévisible, ce graphique vous offre deux options : a) Vous aurez la possibilité de brasser un style de bière qui correspond a peu prés à la couleur indiquée au dessus de l’alcalinité permanente. b) Vous pourrez estimer la quantité de calcium ou de bicarbonates a ajouter a votre eau de brassage pour obtenir l’alcalinité permanente souhaite, celle qui correspondra au mieux a la couleur de bière que vous souhaitez brasser. Je fais vous expliquer comment le faire dans l’exemple suivant : 

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

'''Détermination du style de biere qui correspond le mieux a votre eau de brassage '''1. Un rapport d’analyse de l’eau de Los Angeles, Californie, stipule que les concentrations des trois ions sont : Ca (ppm) = 70 Mg (ppm) =30 Alcalinité = 120 ppm (Comme CaCO3) 2. Marquer ces valeurs sur les échelles correspondantes. (Comme indiquer ci-dessous par des cercles rouges et verts) 

''1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)''

 [[Image:15 3 3 1.gif]]

 

3. Tirer une line entre les valeurs Ca et Mg pour déterminer la dureté effective. (Comme indiquer par un carré rouge) 4. En partant de la valeur de la dureté effective, tracer une ligne qui passe par la valeur de l’alcalinité(le cercle vert) et coupe l’échelle de RA/pH. L’intersection représente votre pH estime dans le cadre d’un brassage avec des malts de base uniquement a savoir 5.8 (le carre bleu). Le taux d’acidité dans 5. En regardant directement au dessus de l’échelle des pH, le guide de couleur vous indique la plage de couleur qui correspond a la plupart des bières ambrées, rousses, brunes et lagers. La plupart des recettes de pale Ale, Brown Ale, et Porter pourront être brassées avec confiance. L’acidité contenue dans ces grains spéciaux sera suffisante pour neutraliser l’alcalinité permanente pour arriver au pH de votre maiche (de 5.8 a 5.2-5.6 dependant du style et de la couleur de biere) . 

''3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).''

'''Détermination de la quantité de Calcium nécessaire pour faire baisser le pH de votre brassin. '''

Mais comment faire pour brasser une bière plus pale comme une Pilsener ou une Helles ? Vous devez dans ce cas ajouter du calcium à votre eau de brassage pour neutraliser l’alcalinité de votre sélection de malt ne peut pas. 

 

1. Reprenons le graphique précédent et prenons un point sur l’échelle RA qui corresponde à la couleur de la biere que vous souhaitez réaliser. Dans l’exemple ci dessous j ai utilise un point correspondant a une alcalinité permanente réduite de 50 point.

''1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.''

 [[Image:15 3 3 2.gif]]

 

2. Traçons une ligne allant du point de RA souhaite vers l’alcalinité effective. 3. En partant maintenant de point correspondant a votre teneur en magnésium , tracer une ligne passant par le nouveau point de d’alcalinité effective et déterminer ainsi un nouveau point sur l’échelle de Calcium donnant la quantité nécessaire pour produire la dureté effective désirée. 4. Soustrayiez la valeur initiale de Ca de la valeur obtenue pour déterminer combien de calcium (par gallon) vous devez ajouter. Dans cet exemple il faut ajouter 145ppm/gal de Calcium. 5. La source de calcium peut être du chlorure de calcium ou du sulfate de calcium (gypse). Referez-vous à la section suivante pour savoir combien de ces sels vous devez ajouter. 

''2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.''

'''Détermination de la dose de carbonate à ajouter pour augmenter le pH de votre brassin '''De la même manière, vous pouvez déterminer combien d’alcalinité additionnelle sera nécessaire pour brasser une Stout foncée si votre eau est faible en alcalinité. 

''Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.''

 [[Image:15 3 3 3.gif]]

 

1. Déterminez votre RA initiale ainsi que le pH pour une recette exclusivement avec des malts de base, déterminez ensuite la valeur de RA désirée pour le style de bière que vous désirez brasser. Dans cet exemple, J ai sélectionné une RA de 180 (ph 6 pour une recette malt de base), ce qui correspond a une bière brune dans le guide de couleur. 2. Cette fois ci vous tracer une ligne partant de ce point vers le point de votre dureté effective, en passant par une nouvelle alcalinité CaCO3. 3. Soustrayiez l’alcalinité originale de l’alcalinité que vous venez de déterminer pour obtenir la quantité de bicarbonate a ajouter. Le bicarbonate ajoute peut provenir de bicarbonate de sodium (de la levure chimique) ou bien de carbonate de calcium. Utiliser du carbonate de calcium aura une influence sur la dureté effective, obligeant à réévaluer le système complet, mais utilisant du bicarbonate de sodium vous allez aussi influencer les taux de sodium, qui pourrait se traduire par un gout acre dans la bière finie a des niveaux élevé. Vous serez probablement amener à ajouter un peu des deux pour obtenir le bon niveau de carbonate sans ajouter trop de sodium ou de calcium. 

''1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.''

Note: La version de ce document grandeur nature contient une corrélation numérique approximative avec l’échelle des couleurs (l’échelle SRM). Elle a pour but de vous aidez à définir le taux alcalinité résiduelle base sur la couleur du style de la bière désirée, mais ce n’est qu’une approximation. Il y a de nombreuses variations dans la relation couleur du malt et acidité du malt.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:15 3 3 4.gif]] Figure 81: Version gradeur nature du graphique permettant l'estumation du ph de votre brassin en fonction du profil de votre eau.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download a n Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4). 

 

== 15.4 Utilisation de sel pour modification de votre eau de brassage ==

 

L'eau de brassage peut etre modifiee (jusqu'a un certain point) par adjonction de sels. Malheureusement, l'ajout de sels dans l'eau ne suit pas la logique 2 + 2 = 4, mais plutot 3.9 ou 4.1 cela depends. La chimie de l'eau peut-etre compliquee; les regles comportent des exception et des limites dans lesquelles d'autres regles avec d'autres exceptions s'appliqueront.

''Brewing water can be adjusted (to a degree) by the addition of brewing salts. Unfortunately, the addition of salts to water is not a matter of 2 + 2 = 4, it tends to be 3.9 or 4.1, depending. Water chemistry can be complicated; the rules contain exceptions and thresholds where other rules and exceptions take over. ''

Heureusement dans la plupart des cas, vous n'aurez pas besoin d'etre trop rigoureux. Vous pourrrez ajouter les ions neceesaire a votre brassage a partir de sels que vous trouverez facilemement. Pour determiner combien vous en ajouter, utiliser le graphique ci dessus ou tout autre graphique pour determiner les concentrations recherchees auxquelles vous pourrez soustraire les concentration deja presente dans votre eau. Ensuite consulter la table 16 pour savoir quel sera l'apport en ion de certains sels. N'oubliez pas de multiplier le resultat obtenu par le volume total d'eau a traiter.  

''Fortunately for most practical applications, you do not have to be that rigorous. You can add needed ions to your water with easily obtainable salts. To calculate how much to add, use the nomograph or another water chart to figure out what concentration is desired and then subtract your water's ion concentration to determine the difference. Next, consult Table 16 to see how much of an ion a particular salt can be expected to add. Don't forget to multiply the difference in concentration by the total volume of water you are working with.''

Reprenons notre exemple sur le graphique qui nous a permis de determiner qu'il nous fallait 145 ppm d'ion calcium additionnel. Disons que nous utiliseros 4 gallons pour brassage.

''Let's look back at the nomograph example where we determined that we needed 145 ppm of additional Calcium ion. Let's say that 4 gallons of water are used in the mash.''

Choisissez le sel que vous allez utiliser pour ajouter du calcium. Utilisons du gypse pour notre exemple.

''Choose a salt to use to add the needed calcium. Let's use gypsum.''

La table 16, nous indique que le gypse ajoute 61.5 ppm de Calcium par gramme a un gallon d'eau.  ''From Table 16, gypsum adds 61.5 ppm of Ca per gram of gypsum added to 1 gallon of water.''

Divisons 144 ppm par 61.5 pour determiner le poids necessaire de gypse a ajouter par gallons pour obtenir la cocentration desiree (145/61.5 = 2,4 g).

Ensuite, multiplions le nombre de grammes par gallons pa rle nombre de gallons a utiliser dans le brassage (4)/ 2.4 x 4 = 9.6 g, que nous pourrons arrondir a 10 grammes. Divide the 145 ppm by 61.5 to determine the number of grams of gypsum needed per gallon to make the desired concentration. 145/61.5 = 2.4 grams Next, multiply the number of grams per gallon by the number of gallons in the mash (4). 2.4 x 4 = 9.6 grams, which can be rounded to 10 grams. <strike>Unless you have a gram scale handy, you will want to convert that to teaspoons which is more convenient. There are 4 grams of gypsum per teaspoon, which gives us 10/4 = 2.5 teaspoons of gypsum to be added to the mash. </strike>

Lastly, you need to realize how much sulfate this addition has made. 2.5 grams per gallon equals 368 ppm of sulfate added to the mash, which is a lot. In this case, it would probably be a good idea to use calcium chloride for half of the addition.

The following table provides information on the use and results of each salt's addition. Brewing salts should be used sparingly to make up for gross deficiencies or overabundance of ions. The concentrations given in Table 16 below are for 1 gram dissolved in 1 gallon of distilled water. Dissolution of 1 gram of a salt in your water will result in a different value due to your water's specific mineral content and pH. However, the results should be reasonably close. Please refer to Appendix F - Recommended Reading, for better discussions of water chemistry and brewing water adjustment than I can provide here.

Table 16 - Salts for Water Adjustment

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Brewing Saltand Common Name
| Concentration at 1 gram/gallon
| Grams per level teaspoon
| Effects
| Comments
|-
| Calcium Carbonate (CaCO3) a.k.a. Chalk
| 105 ppm Ca+2158 ppm CO3-2
| 1.8
| Raises pH
| Because of its limited solubility it is only effective when added directly to the mash. Use for making dark beers in areas of soft water. Use nomograph and monitor the mash pH with pH test papers to determine how much to add.
|-
| Calcium Sulfate (CaSO4*2 H2O) a.k.a. Gypsum
| 61.5 ppm Ca+2 147.4 ppm SO4-2
| 4.0
| Lowers pH
| Useful for adding calcium if the water is low in sulfate. Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Calcium Chloride (CaCl2*2H2O)
| 72 ppm Ca+2 127 ppm Cl-1
| 3.4
| Lowers pH
| Useful for adding Calcium if the water is low in chlorides.
|-
| Magnesium Sulfate (MgSO4*7H2O) a.k.a. Epsom Salt
| 26 ppm Mg+2 103 ppm SO4-2
| 4.5
| Lowers pH by a small amount.
| Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Sodium Bicarbonate (NaHCO3) a.k.a. Baking Soda
| 75 ppm Na+1 191 ppm HCO3-
| 4.4
| Raises pH by adding alkalinity.
| If your pH is too low and/or has low residual alkalinity, then you can add alkalinity. See procedure for calcium carbonate.
|}

 My final advice on the matter is that if you want to brew a pale beer and have water that is very high in carbonates and low in calcium, then your best bet is to use bottled water* from the store or to dilute your water with distilled water and add gypsum or calcium chloride to make up the calcium deficit. Watch your sulfate and chloride counts though. Mineral dilution with water is not as straightforward as it is with wort dilution, due to the various ion buffering effects, but it will be reasonably close. Good Luck!

*You should be able to get an analysis of the bottled water by calling the manufacturer. I have done this with a couple of different brands.

References Fix, G., Fix, L., An Analysis of Brewing Techniques, Brewers Publications, Boulder Colorado, 1997.

DeLange, AJ, personal communication, 1998.

Daniels, R., Designing Great Beers, Brewers Publications, Boulder Colorado, 1997.

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-16T16:07:27Z

Belix :

= Chapter 15 - Comprendre le pH de la maische =

== De quelle type d'eau j'ai besoin? ==

"De quelle type d'eau ai je besoin pour brasser tout-grain?" (vous demandez vous) Normalement, l'eau devrait etre d'une durete moderee et d'une aclinite de basse a moderee, mais ca depend ... "Qu'est ce que signifie ces termes? De quoi cela depend?" "Ou puis je obtenir ce type d'eau?" "A quelle eau ressemble mon eau?" ''What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?" '' 

Ce chapitre vous permettra de repondre a ces questions. Les reponses vont dependre du type de biere que vous voulez brasser et the profil mineral de l'eau que vous allez utiliser.

''This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.''

 

Le terme durete se refere au taux d'ions calcium et magnesium cintenu dans l'eau. Une eau dure va communement produire des depots dans les tuyaux. La durete de l'eau est liee pour une grande partie a l'acalinite de l'eau. Une eau alcaline est riche en bicarbonates. Une eau tres alcalines conduira le pH de votre maische plus eleve qu'il serait normalement. L'utilisation de malt fonce pourra contre-balance l'alcalinite de l'eau pour obtenir un pH adequat de votre maische, et ce principe va etre explorer dans ce chapite.

''The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.''

 

== 15.1 Reading a Water Report ==

Pour comprendre votre eau, vous avez besoin d'une copie de l'analyse de l'eau de votre reseau. Prenez contact avec votre mairie ou avec la societe de distribution et demandez leur une copie, generalement ils vous en enverrins une gratuitement. Un example pour la ville de Los Angeles est montre dans la Table 12. Les rapports d'analyse d'eau sont principalement oriente par la legislation sur la qualite de l'eau potable et axes sur les poluants comme les pesticides, les bacteries ou les metaux lourds. En tant que brasseur, nous nous interesserons a partie concernant les mineraux qui infulencent le gout et le pH. 

''To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. ''

Il y a plusieurs ions a prendre en considerartion quand il s'agit d'evaluer votre eau de brassage. The principaux ions sont le Calcium (Ca+2), le Magnesium (Mg+2), les carbonates (HCO3-1), et les sulfates (SO4-2). le sodium (Na+1), le chore (Cl-1), et les sulfates (SO4-2) peuvent influencer le gout de l'eau et de la biere, mais eux n'affecte pas le pH de votre maiche <strike>(NDT: j'ai enleve le comme les autres eu egard aux sulfates qui sont dans les deux </strike>). la concenration en ions de l'eau est generalement mesuree an partie par million (ppm), ce qui est correspond a 1 mg de la substance par litre d'eau (mg/l). Vous trouverez la description des ions a la suite de la table ci-dessous.

''There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.''

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Niveau recommande NS =  pas de standard defini ND = Pas detecte 

'''''*'''= Recommended Level NS = No Standard ND = Not Detected''

'''Calcium (Ca+2)'''

Poids atomique = 40.0

Poids equivalent = 20.0

Tolerance pour le brassage = 50 a 150 ppm

Le calcium est le principal ion derterminant la durete de l'eau et a une charge +2. Tout comme il l'est pour notre corps, le calcium est necessaire a beaucoup de levures, d'enzymes, de reaction proteinique, aussi bien lors de l'empatage que de l'ebulition. Il favorise la transparence, le gout, et la stabilite de biere finie. L'addition de Calcium peut etre necessaire pour assurer une activite suffisantes des enzymes lors de brassage avec une eau faible en calcium. Le calcium qui est combine au bicarbonate est aussi connue comme la "durete temporaire ou carbonatee". La durete temporaire peut etre supprimer par ebulition (voir bicarbonates). Le calcium qui subsite apres que l'on est supprime la durete tempraire est appele durete permanente

 Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Poids atomique = 24,3 Masse équivalente = 12.1 Domaine de brassage : de 10 a 30 ppm Cet ion agit de la manière que le calcium dans l’eau, mais avec moins d’efficacité. Il contribue lui aussi a la dureté de l’eau. Le Magnésium est un nutriment important des levures dans de faible quantité (10-20 ppm), mais des niveaux supérieurs à 50 ppm tendent a donner gout aigre-amer à la bière. Des niveaux supérieur à 125 ppm ont des effets laxatifs et diurétiques. 

''Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.''

'''Bicarbonate (HCO3-1) ''' Poids moléculaire = 61.0 Masse équivalente = 61 Niveaux pour le brassage = de 0 à 50 ppm pour les bières blondes, de 50 à 150 ppm pour les bières ambrées, de 125 à 250 pour les bières brunes, foncées. Les ions de la famille des carbonates sont très importants dans l’évaluation d’une eau de brassage. Le carbonate (CO3-2), est un ion alcalin, qui augmente le pH, et neutralise l’acidité des malts fonces. Son cousin, le bicarbonate (HCO3-1), a un pouvoir tampon divise par deux, mais est dominant dans les caractéristiques chimiques de l’eau de brassage car c’est la forme principale de carbonates dans les eaux ayant un pH inferieur à 8.4. Le carbonate, lui, représente généralement moins de 1% du total des carbonate/bicarbonate/acide carbonique présents dans les eaux avec un pH inferieur à 8.4. Il existe deux méthodes que les brasseurs peuvent utiliser pour réduire la concentration a un niveau de 50 a 150 ppm approprie pour la plupart de ale blonde, voir même a des niveaux inferieurs pour des lagers comme les pilseners. Ces méthodes sont l’ébullition et la dilution. 

 

''Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.''

Les carbonates peuvent être précipités sous forme de carbonate de calcium (CaCO3) par aération et ébullition par le biais de la réaction suivante : 

2 HCO3-1 + CA+2 + O2 (gazeux) --> CacO3 + H2O + CO2 (gazeux) 

Dans cette réaction l’oxygène provenant de l’aération agit comme un catalyseur and la chaleur due à l’ébullition empêche la re-dissolution du CO2 produit qui pourrait avoir lieu sous forme d’acide carbonique. 

''Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:''

'' 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas''

'' where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.''

La dilution est la méthode la plus simple pour produire une eau faiblement carbonatée. Utiliser de l’eau distillée que vous vous procurer facilement (Elle est souvent utilisée pour les fers à repasser à vapeur) dans une proportion de 1 pou 1, et vous réduirez ainsi par deux le taux de carbonates, vous obtiendrez cependant une légère différence due à des réactions tampons.

''Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.''

'''Sulfate (SO4-2)''' Poids moléculaire = 96.0 Masse équivalente = 48 Niveaux recommandes pour le brassage = 50 a 150 ppm pour les bières normalement houblonnées (amères), et de 150 a 350 pour les bières fortement houblonnées (fortement amères). 

''Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers ''

L’ion sulfate se combine aussi avec le Calcium ou le Magnésium et contribue a la dureté permanente. Il accentue l’amertume, produisant un effet plus sec de l’amertume, plus pétillant/tranchant. A des concentrations supérieures a 400ppm, il me conduire l’amertume a un caractère astringent et désagréable, et à des concentrations supérieures a 750 ppm il cause des diarrhées. Le sulfate a seulement un pouvoir faiblement alcalin et ne contribue par a l’alcalinité globale de l’eau.

''The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.''

'''Sodium (Na+1) ''' Poids atomique = 22.9. Masse équivalente = 22.9. Niveaux recommandes pour le brassage = de 0 a 150 ppm.

''Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. ''

Le sodium peut être présent a des concentrations très importantes, particulièrement si vous utilisez adoucisseur a base de sels (cad par échangeur d’ions) a la maison. En général vous ne devez jamais utiliser d’eau adoucie pour brasser. Vous aurez en effet surement besoin du Calcium qui sera remplace, et vous n’aurez clairement pas besoin des niveaux de sodium élevés qui seront produit. A des niveaux de 70 à 150 ppm il contribue à arrondir le gout de la bière, et accentue le coté doux du malt. Mais au dessus de 200ppm la bière va commencer à avoir un gout sale. La combinaison de sodium avec une forte concentration d’ions sulfate va génère une amertume très agressive. Ainsi il convient de tenir la concentration d’au moins un des ces ions a des niveaux aussi pas que possible, et de préférence celui du sodium.

Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chlorure (Cl-1)''' Poids atomique = 35.4 Masse équivalente = 35.4 Niveaux recommandes pour le brassage = De 0 a 250 ppm 

''Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm.''

L’ion chlore contribue au gout et la plénitude gustative d’une bière. Des concentrations supérieures a 300pm (dans des eaux fortement chlorées, ou résultant de résidus de désinfectant javellisé) peut conduire a des gouts médicamenteux du aux composes chlorophenol.

'' The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.''

'''Durete de l’eau, Alcilinite et milliEquivalence'''

La dureté et l’alcalinité de l’eau sont souvent exprimées comme « CaCO3 ». La dureté se référant à la concentration de cation, et l’alcalinité a celles des anions cad bicarbonate. Si l’analyse de votre eau ne spécifie pas les niveaux d’ion bicarbonate, ni l’alcalinité ou les dosages de CaCO3, pour vous donner une idee du pouvoir tampon de votre eau, vous aurez besoin de téléphoner les département gérant les eaux et demander à parler a un de leurs ingénieurs. Ils disposeront de cette information.

''Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.''

Le Calcium, et a un niveau moins important le Magnésium se combinent avec les bicarbonates pour formes du calcaire qui est très peu soluble dans une eau à pH neutre (7.0). La concentration totale de ces deux ions dans l’eau est appelée dureté et est le plus décelable aux dépôts calcaires dans la tuyauterie. La dureté de l’eau est souvent nommée dans les analyses municipales de l’eau comme dureté « CaCo3 » et est égale a la somme des concentrations en milliEquivalent (mEq/l) multiplie par 50 (la masse équivalente du CaCO3). Un équivalent est une mole d’un ion avec une charge +1 ou -1. La Masse équivalente du Ca+2 est la moitie de son poids atomique de 40 cad 20. Ainsi si vous divisez la concentration en ppm ou en mg/l du Ca+2 par 20 vous obtenez le nombre de milliEquivalent par litre de ca+2. En additionnant le nombre de milliequivalent de Calcium et de Magnésium puis en multipliant par 50 vous obtenez la dureté en milliEquivalent par litre de CaCO3.

''Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.''

(CA (ppm)/20 + mg(ppm)/12.1) x 50 = La dureté totale sous forme CaCO3.

''(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3''

Ces operations sont resumees dans la table suivante:

''These operations are summarized in the following table.''

Table 13 - Table de conversion de la concentration des ions.

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 '''Ph de l’eau ''' 

Vous devez penser que le pH de l’eau est important mais en fait il ne l’est pas. C’est le pH de la maiche qui est important. Et cette valeur dépend des tous ions présents dont nous avons déjà discuté. En fait, la concentration des ions n’est a prendre en considération telle quelle, et ce tant que l’eau n’est pas mélangée avec l’ensemble des grains, c’est le pH de ce mélange (NDT la maiche) qui doit être déterminé, et c’est ce pH qui affectera l’activité enzymatique lors de l’empattage ainsi que le niveau d’extraction des tannins astringent de l’enveloppe des grains.

''You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks.''

  De nombreux brasseurs se sont trompes en essayant de modifier le pH de leur eau avec des sels et des acides pour obtenir le pH désiré pour la maiche avant d’ajouter les malts. Vous pouvez le faire si vous avez suffisamment d’expérience avec une recette particulière qui vous permet de déterminer le pH résultant ; mais c’est un peu comme mettre la charrue avant les bœufs. Il est préférable de commencer l’empattage, vérifier le pH avec un papier pH et ensuite faire les ajustements que vous jugerez nécessaire pour obtenir le pH désiré. La plupart du temps ces ajustements ne seront pas nécessaires.

''Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.''

Cependant, beaucoup de personnes n’aiment pas faire confiance a la chance ou procéder par essai successifs en mesurant le pH de la maiche avec un papier pH et ajoutant des sels pour obtenir le bon PH. Il estime un moyen d’estimer le pH de votre maiche avant de commencer l’empattage et cette méthode sera développée dans la section suivante, mais d’abord voyons comment les grains affectent le pH de la maiche.

''However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.''

== 15.2 Equilibrage des malts et des minéraux ==

Si vous brassez en n'utilisant que du malt blond de base avec de l'eau distillée, vous obtiendrez habituellement une maishe avec un pH entre 5.7-5.8. (Rappelez-vous, que la plage idéale est un pH de 5.1-5.5). L'adjonction de malts spéciaux à l'acidité naturelle (par exemple le caramel, chocolat, ou noir) va avoir un effet important sur le pH de la maishe. Ainsi l'utilisation d'un malt cristal foncé ou grillé, à hauteur de 20% du grain, réduira souvent le pH d'une demi-unité (.5 pH). En utilisant de l'eau distillée et 100% de malt caramel on obtiendra normalement une maishe avec un pH de 4.5-4.8, avec du malt chocolat un ph de 4.3-4.5, et avec du malt noir un pH de 4.0-4.2. De son coté la composition de l'eau va elle influencer ou compenser l'effet que pourrait avoir ces malts spéciaux sur le pH de la maishe. La meilleure manière d'expliquer le phénomène est de décrire deux des bières les plus célèbres au monde et leurs eaux de brassage.La région de Pilsen en République Tchèque est le berceau de la bière de type Pilsener. La Pils est une bière blonde allemande dorée, sèche et limpide avec un goût de houblon particulier. L'eau de Pilsen est très douce, exempte de la plupart des sels minéraux et très pauvre en bicarbonates. Les brasseurs avaient pris l'habitude d'utiliser un acidifiant pour réduire le pH de la maishe, à base uniquement de malts blond de pilsen, à 5.1 - 5.5. 

 ''When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.''

Table 14 - Influence du profil de l'eau locale. 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

Extrait de "American Handy Book", 2:790, Wahl-Henius, 1902

L'autre bière à considérer est la Guinness, la célèbre bière Irlandaise. L'eau d'Irlande est riche en bicarbonates (HCO3-1), et a une quantité considérable de calcium mais pas suffisament pour équilibrer le bicarbonate. Ceci a comme conséquence une eau dure et alkaline avec une forte capacité de dosage. L'alcalinité élevée de l'eau rend difficile la production de bière blondes sans une amertume prononcée. En effet l'eau utilisée ne permet pas au pH de la maishe a base de malt, de baisser suffisamment pour atteindre la plage cible de ph de 5 - 5.8. Ce pH élevé induisant l'extraction élevé de composés phénoliques et de tanins amers provenant de l’enveloppe du grain. Un pH inférieur, (5.2-5.5) optimal pour une maishe, empêche normalement l’apparition de ces composés dans le produit final. Mais alors comment cette région du monde peut-elle être renommée pour produire les bières foncées exceptionnelles? La raison est en fait le malt foncé lui-même. En effet les malts noirs utilisés, fortement grillés, conduisaient naturellement Guinness à augmenter l'acidité de la maishe. L'acidité de ces malts neutralisant le pH élevé de l'eau, le pH de la maishe s’abaisse naturellement pour atteindre la plage de pH optimale.

''The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.''

Ainsi une bonne bière foncée ne pourrait pas être brassée dans la région de Pilsen, et des bonnes bières blondes légères allemandes dans la région de Dublin sans l'adjonction rigoureuse de sels minéraux appropries.Avant que vous brassiez votre première bière en tout-grain, vous devez obtenir la fiche d’analyse de votre eau de brassage et vérifier le profil minérale pour établir quels styles de bières en tireront avantage. L’utilisation de malts grilles comme du le caramel, chocolat, ou le Noir, ou de malt toaste comme le Munich ou le Vienne, sera fructueuse dans des régions ou l’eau est alcaline (cad, un pH supérieur a 7.5 et un niveau de carbonates supérieur a 200 ppm) et produiront des conditions idéales pour le brassage. Si vous vivez dans une région ou l’eau est très douce (comme Pilsen), alors vous pourrez ajouter des sels a votre eau de brassage et de rinçage pour obtenir le pH desire. Les deux sections suivantes de ce chapitre, Alcalinité résiduelle et pH de votre maiche, et utilisation des sels pour ajuster votre eau de brassage, vous aiderons dans cette démarche.

''The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.''

La table suivante liste un certain de style classique de bières ainsi que le profil de l’eau de la région ou elles sont brassées. En examinant la ville et le type de bières brassées, vous pourrez apprécier comment la chimie du malt et celle de l’eau interagissent. La description de la région et des styles de bière sont données ci-dessous :

''The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.''

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Style de biere 
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

Pilsen -

La faible dureté de l’eau et de son alcalinité permettre d’obtenir le pH désiré uniquement avec des malts de base, obtenant ainsi la douce saveur du pain frais. The manque de sulfate attenue l’amertume du houblon ce qui permet de ne pas dénaturer la douceur du caractère malté ; l’arome d’un houblon noble y est sublime.

''The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.''

Dortmund -

Une autre ville célèbre pour ces lagers pales, les Dormunt export ont un caractère moins houblonné que les pilsner, avec un caractère malte moins prononce dut a des teneurs en minéraux élevées. L’équilibre des minéraux est relativement similaire a celui de Vienne, mais la bière a plus de corps, plus sèche et plus pale.

''Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.''

Vienne -

L’eau de cette ville est très similaire a celle de dormant, mais manqué de calcium pour contre balancer les carbonates, et manque aussi de sodium et de chlore pour le gout. Les tentatives pour imiter les Dormunt Export furent des échecs cuisants jusqu'à ce que le pourcentage de malt toaste soit augmente pour équilibrer les brassins, ce qui donna naissance a cette fameuse bière rousse de Vienne.

''The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.''

Munich -

 Bien que d’un profil modéré en ce qui concerne la plupart des minéraux, l’alcalinité provenant des carbonates est élevée. Les aromes doux des dunkels, bocks ou autres oktoberfest de la région mette en avant le succès de l’utilisation de malts fonce pour contre balance les carbonates et acidifie la maiche. Le taux relativement bas de sulfate confère une amertume du houblon moins prononcée mettant en valeur les aromes de malt.

''Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.''

Londres -

Le taux de carbonate le plus élevé oblige l’utilisation de malt fonces pour equilibrer la maiche, mais le chlorure et le niveau eleve de sodium permetent d’adoucir les aromes, dont les resultats sous forme de porter fonces et de pale ale cuivrees sont bien connus.

''The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.''

Edinburgh -

Pensez aux brumeuses soirées écossaises et pensez aux robustes Scottish Ale – avec des reflets d’un rouge profond, des aromes doux de malt et d’agréable aromes de houblon en fin de bouche. L’eau est similaire a celle de Londres mais un peu moins carbonatée et mois de sulfate, se traduisant par une bière qui peut se permettre un corps plus malte avec un utilisation moins prononcée de houblons pour équilibrer ces bières.

''Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.''

Burton-on-Trent -

 Comparée a Londres, le calcium et le sulfate est remarquablement élevé, mais la dureté de l’eau et son alcalinité sont équivalent a ceux de pilsen. Le taux élevé de sulfate et le faible taux de sodium produisent une amertume franche mais pas trop prononcée. Comparées aux ales de Londres, celles de Burton sont plus pale, mais plus amères, bien que l’amertume soit atténuée par un taux d’alcool plus élevé et la corpulence de ces ales.

''Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.''

Dublin -

Fameuse pour ces Stout, Dublin à le taux de bicarbonate le plus élevé de toutes les iles britanniques, et l’Irlande l’utilise pour faire les bières les plus foncées et les plus maltées du monde. Le faible taux de sodium, de chlorure, et de sulfate contribue a une franche amertume du houblon pour équilibrer le cote très malté.

''Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.''

== 15.3 Alcalinité résiduelle et pH de la maiche ==

 Avant que vous ne commenciez votre premier brassage, vous voudrez probablement vous assurez qu’il se déroule bien. Beaucoup de personnes souhaitent brasser un Stout fonce ou bien une pilsner légère pour leur première expérience, mais ces styles très fonces ou très pales nécessitent une eau de brassage avec un profil bien défini pour obtenir un pH désiré. Alors qu’il n’existe aucun moyen infaillible de prédire le pH exact, il existe des méthodes empiriques and des formules qui peuvent vous y aider, tout comme les calculs d’IBU du houblon. Pour estimer le pH d’une maiche composée uniquement de malt de base, vous aurez besoins de connaître vos taux de calcium, magnésium, et votre alcalinité en vous aidant du rapport d’analyse de votre eau. Malheureusement, vous voudrez rarement brasser une biere en utilisant uniquement que des malts de base.

''Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.''

Pour estimer le pH de votre recette, vous aurez besoin du taux de Calcium, Magnésium, et de l’alcalinité de votre eau mais aussi de la couleur approximative de la bière que vous allez tenter de faire.

''To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.''

Historique: En 1953, P. Kohlbach a détermine que 3.5 Equivalents Calcium réagisse a la phytin du malt pour libérer un équivalent d’ions hydrogène qui pouvait neutraliser 1 équivalent d’alcalinité de l’eau. Le Magnésium, l’autre ion associe a la dureté de l’eau, agit lui aussi mais une moindre mesure, ainsi 7 équivalents sont nécessaire pour neutraliser 1 équivalent d’alcalinité. L’alcalinité qui n’est pas neutralise est appelée alcalinité permanente (RA Residual Alkalinity en Anglais). Base sur le volume, ceci peut être exprime par la formule suivante :

 

''In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: ''

mEq/L RA = mEq/L d’alcalinité – [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] ou mEq/L correspond a milliEquivalent par litre. 

mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

Cette alcalinité permanente conduira une maiche ne contenant que des malts de bases à avoir un pH supérieur a celui désire (cad > 6.0), ce qui conduira a une extraction de tanins, etc. Pour contrecarrer l’alcalinité permanente, les brasseurs ayant une eau alcaline comme celle de Dublin devront ajouter des malts grilles qui ont une acidité naturelle qui permettra au pH de la maiche de descendre au niveau désiré (5.2-5.6). Pour vous aider a déterminer votre alcalinité permanente, et déterminer ce que vous obtiendriez avec une maiche ne contenant que des malts de base, j’ai réuni toutes les informations nécessaire sur le graphique suivant, qui vous permettra de lire directement le pH d’une maiche ne contenant que des malts de base après avoir reporte vos niveau de calcium, Magnésium, et d’alcalinité. Pour utiliser le graphique suivant, vous devez pointer vos niveaux de Calcium, Magnésium pour déterminer une dureté « effective », puis tracer une ligne depuis cette valeur vers votre valeur d’alcalinité pour déterminer votre alcalinité résiduelle et approximer le pH. La dureté effective n’est pas la même que la dureté totale en CaCO3 que vous pourrez trouver sur le rapport d’analyse de votre eau, c’est un calcul de l’effet que le calcium et le magnésium ont sur l’alcalinité.

''This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.''

Apres la détermination de votre alcalinité permanente et le pH prévisible, ce graphique vous offre deux options : a) Vous aurez la possibilité de brasser un style de bière qui correspond a peu prés à la couleur indiquée au dessus de l’alcalinité permanente. b) Vous pourrez estimer la quantité de calcium ou de bicarbonates a ajouter a votre eau de brassage pour obtenir l’alcalinité permanente souhaite, celle qui correspondra au mieux a la couleur de bière que vous souhaitez brasser. Je fais vous expliquer comment le faire dans l’exemple suivant : 

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

'''Détermination du style de biere qui correspond le mieux a votre eau de brassage '''1. Un rapport d’analyse de l’eau de Los Angeles, Californie, stipule que les concentrations des trois ions sont : Ca (ppm) = 70 Mg (ppm) =30 Alcalinité = 120 ppm (Comme CaCO3) 2. Marquer ces valeurs sur les échelles correspondantes. (Comme indiquer ci-dessous par des cercles rouges et verts) 

''1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)''

 [[Image:15 3 3 1.gif]]

 

3. Tirer une line entre les valeurs Ca et Mg pour déterminer la dureté effective. (Comme indiquer par un carré rouge) 4. En partant de la valeur de la dureté effective, tracer une ligne qui passe par la valeur de l’alcalinité(le cercle vert) et coupe l’échelle de RA/pH. L’intersection représente votre pH estime dans le cadre d’un brassage avec des malts de base uniquement a savoir 5.8 (le carre bleu). Le taux d’acidité dans 5. En regardant directement au dessus de l’échelle des pH, le guide de couleur vous indique la plage de couleur qui correspond a la plupart des bières ambrées, rousses, brunes et lagers. La plupart des recettes de pale Ale, Brown Ale, et Porter pourront être brassées avec confiance. L’acidité contenue dans ces grains spéciaux sera suffisante pour neutraliser l’alcalinité permanente pour arriver au pH de votre maiche (de 5.8 a 5.2-5.6 dependant du style et de la couleur de biere) . 

''3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).''

'''Détermination de la quantité de Calcium nécessaire pour faire baisser le pH de votre brassin. '''

Mais comment faire pour brasser une bière plus pale comme une Pilsener ou une Helles ? Vous devez dans ce cas ajouter du calcium à votre eau de brassage pour neutraliser l’alcalinité de votre sélection de malt ne peut pas. 

1. Reprenons le graphique précédent et prenons un point sur l’échelle RA qui corresponde à la couleur de la biere que vous souhaitez réaliser. Dans l’exemple ci dessous j ai utilise un point correspondant a une alcalinité permanente réduite de 50 point.

''1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.''

 [[Image:15 3 3 2.gif]]

 

2. Traçons une ligne allant du point de RA souhaite vers l’alcalinité effective. 3. En partant maintenant de point correspondant a votre teneur en magnésium , tracer une ligne passant par le nouveau point de d’alcalinité effective et déterminer ainsi un nouveau point sur l’échelle de Calcium donnant la quantité nécessaire pour produire la dureté effective désirée. 4. Soustrayiez la valeur initiale de Ca de la valeur obtenue pour déterminer combien de calcium (par gallon) vous devez ajouter. Dans cet exemple il faut ajouter 145ppm/gal de Calcium. 5. La source de calcium peut être du chlorure de calcium ou du sulfate de calcium (gypse). Referez-vous à la section suivante pour savoir combien de ces sels vous devez ajouter. 

''2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.''

'''Détermination de la dose de carbonate à ajouter pour augmenter le pH de votre brassin '''De la même manière, vous pouvez déterminer combien d’alcalinité additionnelle sera nécessaire pour brasser une Stout foncée si votre eau est faible en alcalinité. 

''Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.''

 [[Image:15 3 3 3.gif]]

 

1. Déterminez votre RA initiale ainsi que le pH pour une recette exclusivement avec des malts de base, déterminez ensuite la valeur de RA désirée pour le style de bière que vous désirez brasser. Dans cet exemple, J ai sélectionné une RA de 180 (ph 6 pour une recette malt de base), ce qui correspond a une bière brune dans le guide de couleur. 2. Cette fois ci vous tracer une ligne partant de ce point vers le point de votre dureté effective, en passant par une nouvelle alcalinité CaCO3. 3. Soustrayiez l’alcalinité originale de l’alcalinité que vous venez de déterminer pour obtenir la quantité de bicarbonate a ajouter. Le bicarbonate ajoute peut provenir de bicarbonate de sodium (de la levure chimique) ou bien de carbonate de calcium. Utiliser du carbonate de calcium aura une influence sur la dureté effective, obligeant à réévaluer le système complet, mais utilisant du bicarbonate de sodium vous allez aussi influencer les taux de sodium, qui pourrait se traduire par un gout acre dans la bière finie a des niveaux élevé. Vous serez probablement amener à ajouter un peu des deux pour obtenir le bon niveau de carbonate sans ajouter trop de sodium ou de calcium. 

''1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.''

Note: La version de ce document grandeur nature contient une corrélation numérique approximative avec l’échelle des couleurs (l’échelle SRM). Elle a pour but de vous aidez à définir le taux alcalinité résiduelle base sur la couleur du style de la bière désirée, mais ce n’est qu’une approximation. Il y a de nombreuses variations dans la relation couleur du malt et acidité du malt.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:15 3 3 4.gif]] Figure 81: Full size nomograph for approximating your mash pH from your local water report. Click to bring up the full size pdf file.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download an Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4). 

 

== 15.4 Using Salts for Brewing Water Adjustment ==

 Brewing water can be adjusted (to a degree) by the addition of brewing salts. Unfortunately, the addition of salts to water is not a matter of 2 + 2 = 4, it tends to be 3.9 or 4.1, depending. Water chemistry can be complicated; the rules contain exceptions and thresholds where other rules and exceptions take over. 

Fortunately for most practical applications, you do not have to be that rigorous. You can add needed ions to your water with easily obtainable salts. To calculate how much to add, use the nomograph or another water chart to figure out what concentration is desired and then subtract your water's ion concentration to determine the difference. Next, consult Table 16 to see how much of an ion a particular salt can be expected to add. Don't forget to multiply the difference in concentration by the total volume of water you are working with.

Let's look back at the nomograph example where we determined that we needed 145 ppm of additional Calcium ion. Let's say that 4 gallons of water are used in the mash.

Choose a salt to use to add the needed calcium. Let's use gypsum. From Table 16, gypsum adds 61.5 ppm of Ca per gram of gypsum added to 1 gallon of water. Divide the 145 ppm by 61.5 to determine the number of grams of gypsum needed per gallon to make the desired concentration. 145/61.5 = 2.4 grams Next, multiply the number of grams per gallon by the number of gallons in the mash (4). 2.4 x 4 = 9.6 grams, which can be rounded to 10 grams. Unless you have a gram scale handy, you will want to convert that to teaspoons which is more convenient. There are 4 grams of gypsum per teaspoon, which gives us 10/4 = 2.5 teaspoons of gypsum to be added to the mash. Lastly, you need to realize how much sulfate this addition has made. 2.5 grams per gallon equals 368 ppm of sulfate added to the mash, which is a lot. In this case, it would probably be a good idea to use calcium chloride for half of the addition.

The following table provides information on the use and results of each salt's addition. Brewing salts should be used sparingly to make up for gross deficiencies or overabundance of ions. The concentrations given in Table 16 below are for 1 gram dissolved in 1 gallon of distilled water. Dissolution of 1 gram of a salt in your water will result in a different value due to your water's specific mineral content and pH. However, the results should be reasonably close. Please refer to Appendix F - Recommended Reading, for better discussions of water chemistry and brewing water adjustment than I can provide here.

Table 16 - Salts for Water Adjustment

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Brewing Saltand Common Name
| Concentration at 1 gram/gallon
| Grams per level teaspoon
| Effects
| Comments
|-
| Calcium Carbonate (CaCO3) a.k.a. Chalk
| 105 ppm Ca+2158 ppm CO3-2
| 1.8
| Raises pH
| Because of its limited solubility it is only effective when added directly to the mash. Use for making dark beers in areas of soft water. Use nomograph and monitor the mash pH with pH test papers to determine how much to add.
|-
| Calcium Sulfate (CaSO4*2 H2O) a.k.a. Gypsum
| 61.5 ppm Ca+2 147.4 ppm SO4-2
| 4.0
| Lowers pH
| Useful for adding calcium if the water is low in sulfate. Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Calcium Chloride (CaCl2*2H2O)
| 72 ppm Ca+2 127 ppm Cl-1
| 3.4
| Lowers pH
| Useful for adding Calcium if the water is low in chlorides.
|-
| Magnesium Sulfate (MgSO4*7H2O) a.k.a. Epsom Salt
| 26 ppm Mg+2 103 ppm SO4-2
| 4.5
| Lowers pH by a small amount.
| Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Sodium Bicarbonate (NaHCO3) a.k.a. Baking Soda
| 75 ppm Na+1 191 ppm HCO3-
| 4.4
| Raises pH by adding alkalinity.
| If your pH is too low and/or has low residual alkalinity, then you can add alkalinity. See procedure for calcium carbonate.
|}

 My final advice on the matter is that if you want to brew a pale beer and have water that is very high in carbonates and low in calcium, then your best bet is to use bottled water* from the store or to dilute your water with distilled water and add gypsum or calcium chloride to make up the calcium deficit. Watch your sulfate and chloride counts though. Mineral dilution with water is not as straightforward as it is with wort dilution, due to the various ion buffering effects, but it will be reasonably close. Good Luck!

*You should be able to get an analysis of the bottled water by calling the manufacturer. I have done this with a couple of different brands.

References Fix, G., Fix, L., An Analysis of Brewing Techniques, Brewers Publications, Boulder Colorado, 1997.

DeLange, AJ, personal communication, 1998.

Daniels, R., Designing Great Beers, Brewers Publications, Boulder Colorado, 1997.

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-16T14:52:50Z

Belix :

= Chapter 15 - Comprendre le pH de la maische =

== De quelle type d'eau j'ai besoin? ==

"De quelle type d'eau ai je besoin pour brasser tout-grain?" (vous demandez vous) Normalement, l'eau devrait etre d'une durete moderee et d'une aclinite de basse a moderee, mais ca depend ... "Qu'est ce que signifie ces termes? De quoi cela depend?" "Ou puis je obtenir ce type d'eau?" "A quelle eau ressemble mon eau?" ''What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?" '' 

Ce chapitre vous permettra de repondre a ces questions. Les reponses vont dependre du type de biere que vous voulez brasser et the profil mineral de l'eau que vous allez utiliser.

''This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.''

 

Le terme durete se refere au taux d'ions calcium et magnesium cintenu dans l'eau. Une eau dure va communement produire des depots dans les tuyaux. La durete de l'eau est liee pour une grande partie a l'acalinite de l'eau. Une eau alcaline est riche en bicarbonates. Une eau tres alcalines conduira le pH de votre maische plus eleve qu'il serait normalement. L'utilisation de malt fonce pourra contre-balance l'alcalinite de l'eau pour obtenir un pH adequat de votre maische, et ce principe va etre explorer dans ce chapite.

''The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.''

 

== 15.1 Reading a Water Report ==

Pour comprendre votre eau, vous avez besoin d'une copie de l'analyse de l'eau de votre reseau. Prenez contact avec votre mairie ou avec la societe de distribution et demandez leur une copie, generalement ils vous en enverrins une gratuitement. Un example pour la ville de Los Angeles est montre dans la Table 12. Les rapports d'analyse d'eau sont principalement oriente par la legislation sur la qualite de l'eau potable et axes sur les poluants comme les pesticides, les bacteries ou les metaux lourds. En tant que brasseur, nous nous interesserons a partie concernant les mineraux qui infulencent le gout et le pH. 

''To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. ''

Il y a plusieurs ions a prendre en considerartion quand il s'agit d'evaluer votre eau de brassage. The principaux ions sont le Calcium (Ca+2), le Magnesium (Mg+2), les carbonates (HCO3-1), et les sulfates (SO4-2). le sodium (Na+1), le chore (Cl-1), et les sulfates (SO4-2) peuvent influencer le gout de l'eau et de la biere, mais eux n'affecte pas le pH de votre maiche <strike>(NDT: j'ai enleve le comme les autres eu egard aux sulfates qui sont dans les deux </strike>). la concenration en ions de l'eau est generalement mesuree an partie par million (ppm), ce qui est correspond a 1 mg de la substance par litre d'eau (mg/l). Vous trouverez la description des ions a la suite de la table ci-dessous.

''There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.''

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Niveau recommande NS =  pas de standard defini ND = Pas detecte 

'''''*'''= Recommended Level NS = No Standard ND = Not Detected''

'''Calcium (Ca+2)'''

Poids atomique = 40.0

Poids equivalent = 20.0

Tolerance pour le brassage = 50 a 150 ppm

Le calcium est le principal ion derterminant la durete de l'eau et a une charge +2. Tout comme il l'est pour notre corps, le calcium est necessaire a beaucoup de levures, d'enzymes, de reaction proteinique, aussi bien lors de l'empatage que de l'ebulition. Il favorise la transparence, le gout, et la stabilite de biere finie. L'addition de Calcium peut etre necessaire pour assurer une activite suffisantes des enzymes lors de brassage avec une eau faible en calcium. Le calcium qui est combine au bicarbonate est aussi connue comme la "durete temporaire ou carbonatee". La durete temporaire peut etre supprimer par ebulition (voir bicarbonates). Le calcium qui subsite apres que l'on est supprime la durete tempraire est appele durete permanente

 Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Poids atomique = 24,3 Masse équivalente = 12.1 Domaine de brassage : de 10 a 30 ppm Cet ion agit de la manière que le calcium dans l’eau, mais avec moins d’efficacité. Il contribue lui aussi a la dureté de l’eau. Le Magnésium est un nutriment important des levures dans de faible quantité (10-20 ppm), mais des niveaux supérieurs à 50 ppm tendent a donner gout aigre-amer à la bière. Des niveaux supérieur à 125 ppm ont des effets laxatifs et diurétiques. 

''Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.''

'''Bicarbonate (HCO3-1) ''' Poids moléculaire = 61.0 Masse équivalente = 61 Niveaux pour le brassage = de 0 à 50 ppm pour les bières blondes, de 50 à 150 ppm pour les bières ambrées, de 125 à 250 pour les bières brunes, foncées. Les ions de la famille des carbonates sont très importants dans l’évaluation d’une eau de brassage. Le carbonate (CO3-2), est un ion alcalin, qui augmente le pH, et neutralise l’acidité des malts fonces. Son cousin, le bicarbonate (HCO3-1), a un pouvoir tampon divise par deux, mais est dominant dans les caractéristiques chimiques de l’eau de brassage car c’est la forme principale de carbonates dans les eaux ayant un pH inferieur à 8.4. Le carbonate, lui, représente généralement moins de 1% du total des carbonate/bicarbonate/acide carbonique présents dans les eaux avec un pH inferieur à 8.4. Il existe deux méthodes que les brasseurs peuvent utiliser pour réduire la concentration a un niveau de 50 a 150 ppm approprie pour la plupart de ale blonde, voir même a des niveaux inferieurs pour des lagers comme les pilseners. Ces méthodes sont l’ébullition et la dilution. 

 

''Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.''

Les carbonates peuvent être précipités sous forme de carbonate de calcium (CaCO3) par aération et ébullition par le biais de la réaction suivante : 

2 HCO3-1 + CA+2 + O2 (gazeux) --> CacO3 + H2O + CO2 (gazeux) 

Dans cette réaction l’oxygène provenant de l’aération agit comme un catalyseur and la chaleur due à l’ébullition empêche la re-dissolution du CO2 produit qui pourrait avoir lieu sous forme d’acide carbonique. 

''Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:''

'' 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas''

'' where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.''

La dilution est la méthode la plus simple pour produire une eau faiblement carbonatée. Utiliser de l’eau distillée que vous vous procurer facilement (Elle est souvent utilisée pour les fers à repasser à vapeur) dans une proportion de 1 pou 1, et vous réduirez ainsi par deux le taux de carbonates, vous obtiendrez cependant une légère différence due à des réactions tampons.

''Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.''

'''Sulfate (SO4-2)''' Poids moléculaire = 96.0 Masse équivalente = 48 Niveaux recommandes pour le brassage = 50 a 150 ppm pour les bières normalement houblonnées (amères), et de 150 a 350 pour les bières fortement houblonnées (fortement amères). 

''Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers ''

L’ion sulfate se combine aussi avec le Calcium ou le Magnésium et contribue a la dureté permanente. Il accentue l’amertume, produisant un effet plus sec de l’amertume, plus pétillant/tranchant. A des concentrations supérieures a 400ppm, il me conduire l’amertume a un caractère astringent et désagréable, et à des concentrations supérieures a 750 ppm il cause des diarrhées. Le sulfate a seulement un pouvoir faiblement alcalin et ne contribue par a l’alcalinité globale de l’eau.

''The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.''

'''Sodium (Na+1) ''' Poids atomique = 22.9. Masse équivalente = 22.9. Niveaux recommandes pour le brassage = de 0 a 150 ppm.

''Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. ''

Le sodium peut être présent a des concentrations très importantes, particulièrement si vous utilisez adoucisseur a base de sels (cad par échangeur d’ions) a la maison. En général vous ne devez jamais utiliser d’eau adoucie pour brasser. Vous aurez en effet surement besoin du Calcium qui sera remplace, et vous n’aurez clairement pas besoin des niveaux de sodium élevés qui seront produit. A des niveaux de 70 à 150 ppm il contribue à arrondir le gout de la bière, et accentue le coté doux du malt. Mais au dessus de 200ppm la bière va commencer à avoir un gout sale. La combinaison de sodium avec une forte concentration d’ions sulfate va génère une amertume très agressive. Ainsi il convient de tenir la concentration d’au moins un des ces ions a des niveaux aussi pas que possible, et de préférence celui du sodium.

Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chlorure (Cl-1)''' Poids atomique = 35.4 Masse équivalente = 35.4 Niveaux recommandes pour le brassage = De 0 a 250 ppm 

''Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm.''

L’ion chlore contribue au gout et la plénitude gustative d’une bière. Des concentrations supérieures a 300pm (dans des eaux fortement chlorées, ou résultant de résidus de désinfectant javellisé) peut conduire a des gouts médicamenteux du aux composes chlorophenol.

'' The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.''

'''Durete de l’eau, Alcilinite et milliEquivalence'''

La dureté et l’alcalinité de l’eau sont souvent exprimées comme « CaCO3 ». La dureté se référant à la concentration de cation, et l’alcalinité a celles des anions cad bicarbonate. Si l’analyse de votre eau ne spécifie pas les niveaux d’ion bicarbonate, ni l’alcalinité ou les dosages de CaCO3, pour vous donner une idee du pouvoir tampon de votre eau, vous aurez besoin de téléphoner les département gérant les eaux et demander à parler a un de leurs ingénieurs. Ils disposeront de cette information.

''Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.''

Le Calcium, et a un niveau moins important le Magnésium se combinent avec les bicarbonates pour formes du calcaire qui est très peu soluble dans une eau à pH neutre (7.0). La concentration totale de ces deux ions dans l’eau est appelée dureté et est le plus décelable aux dépôts calcaires dans la tuyauterie. La dureté de l’eau est souvent nommée dans les analyses municipales de l’eau comme dureté « CaCo3 » et est égale a la somme des concentrations en milliEquivalent (mEq/l) multiplie par 50 (la masse équivalente du CaCO3). Un équivalent est une mole d’un ion avec une charge +1 ou -1. La Masse équivalente du Ca+2 est la moitie de son poids atomique de 40 cad 20. Ainsi si vous divisez la concentration en ppm ou en mg/l du Ca+2 par 20 vous obtenez le nombre de milliEquivalent par litre de ca+2. En additionnant le nombre de milliequivalent de Calcium et de Magnésium puis en multipliant par 50 vous obtenez la dureté en milliEquivalent par litre de CaCO3.

''Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.''

(CA (ppm)/20 + mg(ppm)/12.1) x 50 = La dureté totale sous forme CaCO3.

''(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3''

Ces operations sont resumees dans la table suivante:

''These operations are summarized in the following table.''

Table 13 - Table de conversion de la concentration des ions.

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 '''Ph de l’eau ''' 

Vous devez penser que le pH de l’eau est important mais en fait il ne l’est pas. C’est le pH de la maiche qui est important. Et cette valeur dépend des tous ions présents dont nous avons déjà discuté. En fait, la concentration des ions n’est a prendre en considération telle quelle, et ce tant que l’eau n’est pas mélangée avec l’ensemble des grains, c’est le pH de ce mélange (NDT la maiche) qui doit être déterminé, et c’est ce pH qui affectera l’activité enzymatique lors de l’empattage ainsi que le niveau d’extraction des tannins astringent de l’enveloppe des grains.

''You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks.''

  De nombreux brasseurs se sont trompes en essayant de modifier le pH de leur eau avec des sels et des acides pour obtenir le pH désiré pour la maiche avant d’ajouter les malts. Vous pouvez le faire si vous avez suffisamment d’expérience avec une recette particulière qui vous permet de déterminer le pH résultant ; mais c’est un peu comme mettre la charrue avant les bœufs. Il est préférable de commencer l’empattage, vérifier le pH avec un papier pH et ensuite faire les ajustements que vous jugerez nécessaire pour obtenir le pH désiré. La plupart du temps ces ajustements ne seront pas nécessaires.

''Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.''

Cependant, beaucoup de personnes n’aiment pas faire confiance a la chance ou procéder par essai successifs en mesurant le pH de la maiche avec un papier pH et ajoutant des sels pour obtenir le bon PH. Il estime un moyen d’estimer le pH de votre maiche avant de commencer l’empattage et cette méthode sera développée dans la section suivante, mais d’abord voyons comment les grains affectent le pH de la maiche.

''However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.''

== 15.2 Equilibrage des malts et des minéraux ==

Si vous brassez en n'utilisant que du malt blond de base avec de l'eau distillée, vous obtiendrez habituellement une maishe avec un pH entre 5.7-5.8. (Rappelez-vous, que la plage idéale est un pH de 5.1-5.5). L'adjonction de malts spéciaux à l'acidité naturelle (par exemple le caramel, chocolat, ou noir) va avoir un effet important sur le pH de la maishe. Ainsi l'utilisation d'un malt cristal foncé ou grillé, à hauteur de 20% du grain, réduira souvent le pH d'une demi-unité (.5 pH). En utilisant de l'eau distillée et 100% de malt caramel on obtiendra normalement une maishe avec un pH de 4.5-4.8, avec du malt chocolat un ph de 4.3-4.5, et avec du malt noir un pH de 4.0-4.2. De son coté la composition de l'eau va elle influencer ou compenser l'effet que pourrait avoir ces malts spéciaux sur le pH de la maishe. La meilleure manière d'expliquer le phénomène est de décrire deux des bières les plus célèbres au monde et leurs eaux de brassage.La région de Pilsen en République Tchèque est le berceau de la bière de type Pilsener. La Pils est une bière blonde allemande dorée, sèche et limpide avec un goût de houblon particulier. L'eau de Pilsen est très douce, exempte de la plupart des sels minéraux et très pauvre en bicarbonates. Les brasseurs avaient pris l'habitude d'utiliser un acidifiant pour réduire le pH de la maishe, à base uniquement de malts blond de pilsen, à 5.1 - 5.5. 

 ''When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.''

Table 14 - Influence du profil de l'eau locale. 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

Extrait de "American Handy Book", 2:790, Wahl-Henius, 1902

L'autre bière à considérer est la Guinness, la célèbre bière Irlandaise. L'eau d'Irlande est riche en bicarbonates (HCO3-1), et a une quantité considérable de calcium mais pas suffisament pour équilibrer le bicarbonate. Ceci a comme conséquence une eau dure et alkaline avec une forte capacité de dosage. L'alcalinité élevée de l'eau rend difficile la production de bière blondes sans une amertume prononcée. En effet l'eau utilisée ne permet pas au pH de la maishe a base de malt, de baisser suffisamment pour atteindre la plage cible de ph de 5 - 5.8. Ce pH élevé induisant l'extraction élevé de composés phénoliques et de tanins amers provenant de l’enveloppe du grain. Un pH inférieur, (5.2-5.5) optimal pour une maishe, empêche normalement l’apparition de ces composés dans le produit final. Mais alors comment cette région du monde peut-elle être renommée pour produire les bières foncées exceptionnelles? La raison est en fait le malt foncé lui-même. En effet les malts noirs utilisés, fortement grillés, conduisaient naturellement Guinness à augmenter l'acidité de la maishe. L'acidité de ces malts neutralisant le pH élevé de l'eau, le pH de la maishe s’abaisse naturellement pour atteindre la plage de pH optimale.

''The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.''

Ainsi une bonne bière foncée ne pourrait pas être brassée dans la région de Pilsen, et des bonnes bières blondes légères allemandes dans la région de Dublin sans l'adjonction rigoureuse de sels minéraux appropries.Avant que vous brassiez votre première bière en tout-grain, vous devez obtenir la fiche d’analyse de votre eau de brassage et vérifier le profil minérale pour établir quels styles de bières en tireront avantage. L’utilisation de malts grilles comme du le caramel, chocolat, ou le Noir, ou de malt toaste comme le Munich ou le Vienne, sera fructueuse dans des régions ou l’eau est alcaline (cad, un pH supérieur a 7.5 et un niveau de carbonates supérieur a 200 ppm) et produiront des conditions idéales pour le brassage. Si vous vivez dans une région ou l’eau est très douce (comme Pilsen), alors vous pourrez ajouter des sels a votre eau de brassage et de rinçage pour obtenir le pH desire. Les deux sections suivantes de ce chapitre, Alcalinité résiduelle et pH de votre maiche, et utilisation des sels pour ajuster votre eau de brassage, vous aiderons dans cette démarche.

''The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.''

La table suivante liste un certain de style classique de bières ainsi que le profil de l’eau de la région ou elles sont brassées. En examinant la ville et le type de bières brassées, vous pourrez apprécier comment la chimie du malt et celle de l’eau interagissent. La description de la région et des styles de bière sont données ci-dessous :

''The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.''

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Style de biere 
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

Pilsen -

La faible dureté de l’eau et de son alcalinité permettre d’obtenir le pH désiré uniquement avec des malts de base, obtenant ainsi la douce saveur du pain frais. The manque de sulfate attenue l’amertume du houblon ce qui permet de ne pas dénaturer la douceur du caractère malté ; l’arome d’un houblon noble y est sublime.

''The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.''

Dortmund -

Une autre ville célèbre pour ces lagers pales, les Dormunt export ont un caractère moins houblonné que les pilsner, avec un caractère malte moins prononce dut a des teneurs en minéraux élevées. L’équilibre des minéraux est relativement similaire a celui de Vienne, mais la bière a plus de corps, plus sèche et plus pale.

''Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.''

Vienne -

L’eau de cette ville est très similaire a celle de dormant, mais manqué de calcium pour contre balancer les carbonates, et manque aussi de sodium et de chlore pour le gout. Les tentatives pour imiter les Dormunt Export furent des échecs cuisants jusqu'à ce que le pourcentage de malt toaste soit augmente pour équilibrer les brassins, ce qui donna naissance a cette fameuse bière rousse de Vienne.

''The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.''

Munich -

 Bien que d’un profil modéré en ce qui concerne la plupart des minéraux, l’alcalinité provenant des carbonates est élevée. Les aromes doux des dunkels, bocks ou autres oktoberfest de la région mette en avant le succès de l’utilisation de malts fonce pour contre balance les carbonates et acidifie la maiche. Le taux relativement bas de sulfate confère une amertume du houblon moins prononcée mettant en valeur les aromes de malt.

''Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.''

Londres -

Le taux de carbonate le plus élevé oblige l’utilisation de malt fonces pour equilibrer la maiche, mais le chlorure et le niveau eleve de sodium permetent d’adoucir les aromes, dont les resultats sous forme de porter fonces et de pale ale cuivrees sont bien connus.

''The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.''

Edinburgh -

Pensez aux brumeuses soirées écossaises et pensez aux robustes Scottish Ale – avec des reflets d’un rouge profond, des aromes doux de malt et d’agréable aromes de houblon en fin de bouche. L’eau est similaire a celle de Londres mais un peu moins carbonatée et mois de sulfate, se traduisant par une bière qui peut se permettre un corps plus malte avec un utilisation moins prononcée de houblons pour équilibrer ces bières.

''Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.''

Burton-on-Trent -

 Comparée a Londres, le calcium et le sulfate est remarquablement élevé, mais la dureté de l’eau et son alcalinité sont équivalent a ceux de pilsen. Le taux élevé de sulfate et le faible taux de sodium produisent une amertume franche mais pas trop prononcée. Comparées aux ales de Londres, celles de Burton sont plus pale, mais plus amères, bien que l’amertume soit atténuée par un taux d’alcool plus élevé et la corpulence de ces ales.

''Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.''

Dublin -

Fameuse pour ces Stout, Dublin à le taux de bicarbonate le plus élevé de toutes les iles britanniques, et l’Irlande l’utilise pour faire les bières les plus foncées et les plus maltées du monde. Le faible taux de sodium, de chlorure, et de sulfate contribue a une franche amertume du houblon pour équilibrer le cote très malté.

''Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.''

== 15.3 Residual Alkalinity and Mash pH ==

 Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.

To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.

Historique: In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

Determiner le style de biere qui correspond le mieux a votre eau

1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)

 [[Image:15 3 3 1.gif]]

 

3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).

Determination de la quantite Calcium a ajouter pour faire baisser le pH de la maische

But what if you want to brew a much paler beer, like a Pilsener or a Helles? Then you will need to add more calcium to balance the alkalinity that your malt selection cannot.

1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.

 [[Image:15 3 3 2.gif]]

 

2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.

Determination de la quantite de Bicarbonate a ajouter pour augmenter le pH de la maische

 Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.

 [[Image:15 3 3 3.gif]]

 

1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:15 3 3 4.gif]] Figure 81: Full size nomograph for approximating your mash pH from your local water report. Click to bring up the full size pdf file.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download an Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4). 

 

== 15.4 Using Salts for Brewing Water Adjustment ==

 Brewing water can be adjusted (to a degree) by the addition of brewing salts. Unfortunately, the addition of salts to water is not a matter of 2 + 2 = 4, it tends to be 3.9 or 4.1, depending. Water chemistry can be complicated; the rules contain exceptions and thresholds where other rules and exceptions take over. 

Fortunately for most practical applications, you do not have to be that rigorous. You can add needed ions to your water with easily obtainable salts. To calculate how much to add, use the nomograph or another water chart to figure out what concentration is desired and then subtract your water's ion concentration to determine the difference. Next, consult Table 16 to see how much of an ion a particular salt can be expected to add. Don't forget to multiply the difference in concentration by the total volume of water you are working with.

Let's look back at the nomograph example where we determined that we needed 145 ppm of additional Calcium ion. Let's say that 4 gallons of water are used in the mash.

Choose a salt to use to add the needed calcium. Let's use gypsum. From Table 16, gypsum adds 61.5 ppm of Ca per gram of gypsum added to 1 gallon of water. Divide the 145 ppm by 61.5 to determine the number of grams of gypsum needed per gallon to make the desired concentration. 145/61.5 = 2.4 grams Next, multiply the number of grams per gallon by the number of gallons in the mash (4). 2.4 x 4 = 9.6 grams, which can be rounded to 10 grams. Unless you have a gram scale handy, you will want to convert that to teaspoons which is more convenient. There are 4 grams of gypsum per teaspoon, which gives us 10/4 = 2.5 teaspoons of gypsum to be added to the mash. Lastly, you need to realize how much sulfate this addition has made. 2.5 grams per gallon equals 368 ppm of sulfate added to the mash, which is a lot. In this case, it would probably be a good idea to use calcium chloride for half of the addition.

The following table provides information on the use and results of each salt's addition. Brewing salts should be used sparingly to make up for gross deficiencies or overabundance of ions. The concentrations given in Table 16 below are for 1 gram dissolved in 1 gallon of distilled water. Dissolution of 1 gram of a salt in your water will result in a different value due to your water's specific mineral content and pH. However, the results should be reasonably close. Please refer to Appendix F - Recommended Reading, for better discussions of water chemistry and brewing water adjustment than I can provide here.

Table 16 - Salts for Water Adjustment

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Brewing Saltand Common Name
| Concentration at 1 gram/gallon
| Grams per level teaspoon
| Effects
| Comments
|-
| Calcium Carbonate (CaCO3) a.k.a. Chalk
| 105 ppm Ca+2158 ppm CO3-2
| 1.8
| Raises pH
| Because of its limited solubility it is only effective when added directly to the mash. Use for making dark beers in areas of soft water. Use nomograph and monitor the mash pH with pH test papers to determine how much to add.
|-
| Calcium Sulfate (CaSO4*2 H2O) a.k.a. Gypsum
| 61.5 ppm Ca+2 147.4 ppm SO4-2
| 4.0
| Lowers pH
| Useful for adding calcium if the water is low in sulfate. Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Calcium Chloride (CaCl2*2H2O)
| 72 ppm Ca+2 127 ppm Cl-1
| 3.4
| Lowers pH
| Useful for adding Calcium if the water is low in chlorides.
|-
| Magnesium Sulfate (MgSO4*7H2O) a.k.a. Epsom Salt
| 26 ppm Mg+2 103 ppm SO4-2
| 4.5
| Lowers pH by a small amount.
| Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Sodium Bicarbonate (NaHCO3) a.k.a. Baking Soda
| 75 ppm Na+1 191 ppm HCO3-
| 4.4
| Raises pH by adding alkalinity.
| If your pH is too low and/or has low residual alkalinity, then you can add alkalinity. See procedure for calcium carbonate.
|}

 My final advice on the matter is that if you want to brew a pale beer and have water that is very high in carbonates and low in calcium, then your best bet is to use bottled water* from the store or to dilute your water with distilled water and add gypsum or calcium chloride to make up the calcium deficit. Watch your sulfate and chloride counts though. Mineral dilution with water is not as straightforward as it is with wort dilution, due to the various ion buffering effects, but it will be reasonably close. Good Luck!

*You should be able to get an analysis of the bottled water by calling the manufacturer. I have done this with a couple of different brands.

References Fix, G., Fix, L., An Analysis of Brewing Techniques, Brewers Publications, Boulder Colorado, 1997.

DeLange, AJ, personal communication, 1998.

Daniels, R., Designing Great Beers, Brewers Publications, Boulder Colorado, 1997.

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-16T14:38:01Z

Belix :

= Chapter 15 - Comprendre le pH de la maische =

== De quelle type d'eau j'ai besoin? ==

"De quelle type d'eau ai je besoin pour brasser tout-grain?" (vous demandez vous) Normalement, l'eau devrait etre d'une durete moderee et d'une aclinite de basse a moderee, mais ca depend ... "Qu'est ce que signifie ces termes? De quoi cela depend?" "Ou puis je obtenir ce type d'eau?" "A quelle eau ressemble mon eau?" ''What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?" '' 

Ce chapitre vous permettra de repondre a ces questions. Les reponses vont dependre du type de biere que vous voulez brasser et the profil mineral de l'eau que vous allez utiliser.

''This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.''

 

Le terme durete se refere au taux d'ions calcium et magnesium cintenu dans l'eau. Une eau dure va communement produire des depots dans les tuyaux. La durete de l'eau est liee pour une grande partie a l'acalinite de l'eau. Une eau alcaline est riche en bicarbonates. Une eau tres alcalines conduira le pH de votre maische plus eleve qu'il serait normalement. L'utilisation de malt fonce pourra contre-balance l'alcalinite de l'eau pour obtenir un pH adequat de votre maische, et ce principe va etre explorer dans ce chapite.

''The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.''

 

== 15.1 Reading a Water Report ==

Pour comprendre votre eau, vous avez besoin d'une copie de l'analyse de l'eau de votre reseau. Prenez contact avec votre mairie ou avec la societe de distribution et demandez leur une copie, generalement ils vous en enverrins une gratuitement. Un example pour la ville de Los Angeles est montre dans la Table 12. Les rapports d'analyse d'eau sont principalement oriente par la legislation sur la qualite de l'eau potable et axes sur les poluants comme les pesticides, les bacteries ou les metaux lourds. En tant que brasseur, nous nous interesserons a partie concernant les mineraux qui infulencent le gout et le pH. 

''To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. ''

Il y a plusieurs ions a prendre en considerartion quand il s'agit d'evaluer votre eau de brassage. The principaux ions sont le Calcium (Ca+2), le Magnesium (Mg+2), les carbonates (HCO3-1), et les sulfates (SO4-2). le sodium (Na+1), le chore (Cl-1), et les sulfates (SO4-2) peuvent influencer le gout de l'eau et de la biere, mais eux n'affecte pas le pH de votre maiche <strike>(NDT: j'ai enleve le comme les autres eu egard aux sulfates qui sont dans les deux </strike>). la concenration en ions de l'eau est generalement mesuree an partie par million (ppm), ce qui est correspond a 1 mg de la substance par litre d'eau (mg/l). Vous trouverez la description des ions a la suite de la table ci-dessous.

''There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.''

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Niveau recommande NS =  pas de standard defini ND = Pas detecte 

'''''*'''= Recommended Level NS = No Standard ND = Not Detected''

'''Calcium (Ca+2)'''

Poids atomique = 40.0

Poids equivalent = 20.0

Tolerance pour le brassage = 50 a 150 ppm

Le calcium est le principal ion derterminant la durete de l'eau et a une charge +2. Tout comme il l'est pour notre corps, le calcium est necessaire a beaucoup de levures, d'enzymes, de reaction proteinique, aussi bien lors de l'empatage que de l'ebulition. Il favorise la transparence, le gout, et la stabilite de biere finie. L'addition de Calcium peut etre necessaire pour assurer une activite suffisantes des enzymes lors de brassage avec une eau faible en calcium. Le calcium qui est combine au bicarbonate est aussi connue comme la "durete temporaire ou carbonatee". La durete temporaire peut etre supprimer par ebulition (voir bicarbonates). Le calcium qui subsite apres que l'on est supprime la durete tempraire est appele durete permanente

 Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Poids atomique = 24,3 Masse équivalente = 12.1 Domaine de brassage : de 10 a 30 ppm Cet ion agit de la manière que le calcium dans l’eau, mais avec moins d’efficacité. Il contribue lui aussi a la dureté de l’eau. Le Magnésium est un nutriment important des levures dans de faible quantité (10-20 ppm), mais des niveaux supérieurs à 50 ppm tendent a donner gout aigre-amer à la bière. Des niveaux supérieur à 125 ppm ont des effets laxatifs et diurétiques. 

''Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.''

'''Bicarbonate (HCO3-1) ''' Poids moléculaire = 61.0 Masse équivalente = 61 Niveaux pour le brassage = de 0 à 50 ppm pour les bières blondes, de 50 à 150 ppm pour les bières ambrées, de 125 à 250 pour les bières brunes, foncées. Les ions de la famille des carbonates sont très importants dans l’évaluation d’une eau de brassage. Le carbonate (CO3-2), est un ion alcalin, qui augmente le pH, et neutralise l’acidité des malts fonces. Son cousin, le bicarbonate (HCO3-1), a un pouvoir tampon divise par deux, mais est dominant dans les caractéristiques chimiques de l’eau de brassage car c’est la forme principale de carbonates dans les eaux ayant un pH inferieur à 8.4. Le carbonate, lui, représente généralement moins de 1% du total des carbonate/bicarbonate/acide carbonique présents dans les eaux avec un pH inferieur à 8.4. Il existe deux méthodes que les brasseurs peuvent utiliser pour réduire la concentration a un niveau de 50 a 150 ppm approprie pour la plupart de ale blonde, voir même a des niveaux inferieurs pour des lagers comme les pilseners. Ces méthodes sont l’ébullition et la dilution. 

 

''Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.''

Les carbonates peuvent être précipités sous forme de carbonate de calcium (CaCO3) par aération et ébullition par le biais de la réaction suivante : 

2 HCO3-1 + CA+2 + O2 (gazeux) --> CacO3 + H2O + CO2 (gazeux) 

Dans cette réaction l’oxygène provenant de l’aération agit comme un catalyseur and la chaleur due à l’ébullition empêche la re-dissolution du CO2 produit qui pourrait avoir lieu sous forme d’acide carbonique. 

''Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:''

'' 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas''

'' where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.''

La dilution est la méthode la plus simple pour produire une eau faiblement carbonatée. Utiliser de l’eau distillée que vous vous procurer facilement (Elle est souvent utilisée pour les fers à repasser à vapeur) dans une proportion de 1 pou 1, et vous réduirez ainsi par deux le taux de carbonates, vous obtiendrez cependant une légère différence due à des réactions tampons.

''Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.''

'''Sulfate (SO4-2)''' Poids moléculaire = 96.0 Masse équivalente = 48 Niveaux recommandes pour le brassage = 50 a 150 ppm pour les bières normalement houblonnées (amères), et de 150 a 350 pour les bières fortement houblonnées (fortement amères). 

''Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers ''

L’ion sulfate se combine aussi avec le Calcium ou le Magnésium et contribue a la dureté permanente. Il accentue l’amertume, produisant un effet plus sec de l’amertume, plus pétillant/tranchant. A des concentrations supérieures a 400ppm, il me conduire l’amertume a un caractère astringent et désagréable, et à des concentrations supérieures a 750 ppm il cause des diarrhées. Le sulfate a seulement un pouvoir faiblement alcalin et ne contribue par a l’alcalinité globale de l’eau.

''The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.''

'''Sodium (Na+1) ''' Poids atomique = 22.9. Masse équivalente = 22.9. Niveaux recommandes pour le brassage = de 0 a 150 ppm.

''Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. ''

Le sodium peut être présent a des concentrations très importantes, particulièrement si vous utilisez adoucisseur a base de sels (cad par échangeur d’ions) a la maison. En général vous ne devez jamais utiliser d’eau adoucie pour brasser. Vous aurez en effet surement besoin du Calcium qui sera remplace, et vous n’aurez clairement pas besoin des niveaux de sodium élevés qui seront produit. A des niveaux de 70 à 150 ppm il contribue à arrondir le gout de la bière, et accentue le coté doux du malt. Mais au dessus de 200ppm la bière va commencer à avoir un gout sale. La combinaison de sodium avec une forte concentration d’ions sulfate va génère une amertume très agressive. Ainsi il convient de tenir la concentration d’au moins un des ces ions a des niveaux aussi pas que possible, et de préférence celui du sodium.

Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chlorure (Cl-1)''' Poids atomique = 35.4 Masse équivalente = 35.4 Niveaux recommandes pour le brassage = De 0 a 250 ppm 

''Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm.''

L’ion chlore contribue au gout et la plénitude gustative d’une bière. Des concentrations supérieures a 300pm (dans des eaux fortement chlorées, ou résultant de résidus de désinfectant javellisé) peut conduire a des gouts médicamenteux du aux composes chlorophenol.

'' The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.''

'''Durete de l’eau, Alcilinite et milliEquivalence'''

La dureté et l’alcalinité de l’eau sont souvent exprimées comme « CaCO3 ». La dureté se référant à la concentration de cation, et l’alcalinité a celles des anions cad bicarbonate. Si l’analyse de votre eau ne spécifie pas les niveaux d’ion bicarbonate, ni l’alcalinité ou les dosages de CaCO3, pour vous donner une idee du pouvoir tampon de votre eau, vous aurez besoin de téléphoner les département gérant les eaux et demander à parler a un de leurs ingénieurs. Ils disposeront de cette information.

''Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.''

Le Calcium, et a un niveau moins important le Magnésium se combinent avec les bicarbonates pour formes du calcaire qui est très peu soluble dans une eau à pH neutre (7.0). La concentration totale de ces deux ions dans l’eau est appelée dureté et est le plus décelable aux dépôts calcaires dans la tuyauterie. La dureté de l’eau est souvent nommée dans les analyses municipales de l’eau comme dureté « CaCo3 » et est égale a la somme des concentrations en milliEquivalent (mEq/l) multiplie par 50 (la masse équivalente du CaCO3). Un équivalent est une mole d’un ion avec une charge +1 ou -1. La Masse équivalente du Ca+2 est la moitie de son poids atomique de 40 cad 20. Ainsi si vous divisez la concentration en ppm ou en mg/l du Ca+2 par 20 vous obtenez le nombre de milliEquivalent par litre de ca+2. En additionnant le nombre de milliequivalent de Calcium et de Magnésium puis en multipliant par 50 vous obtenez la dureté en milliEquivalent par litre de CaCO3.

''Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.''

(CA (ppm)/20 + mg(ppm)/12.1) x 50 = La dureté totale sous forme CaCO3.

''(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3''

Ces operations sont resumees dans la table suivante:

''These operations are summarized in the following table.''

Table 13 - Table de conversion de la concentration des ions.

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 '''Ph de l’eau ''' 

Vous devez penser que le pH de l’eau est important mais en fait il ne l’est pas. C’est le pH de la maiche qui est important. Et cette valeur dépend des tous ions présents dont nous avons déjà discuté. En fait, la concentration des ions n’est a prendre en considération telle quelle, et ce tant que l’eau n’est pas mélangée avec l’ensemble des grains, c’est le pH de ce mélange (NDT la maiche) qui doit être déterminé, et c’est ce pH qui affectera l’activité enzymatique lors de l’empattage ainsi que le niveau d’extraction des tannins astringent de l’enveloppe des grains.

''You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks.''

  De nombreux brasseurs se sont trompes en essayant de modifier le pH de leur eau avec des sels et des acides pour obtenir le pH désiré pour la maiche avant d’ajouter les malts. Vous pouvez le faire si vous avez suffisamment d’expérience avec une recette particulière qui vous permet de déterminer le pH résultant ; mais c’est un peu comme mettre la charrue avant les bœufs. Il est préférable de commencer l’empattage, vérifier le pH avec un papier pH et ensuite faire les ajustements que vous jugerez nécessaire pour obtenir le pH désiré. La plupart du temps ces ajustements ne seront pas nécessaires.

''Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.''

Cependant, beaucoup de personnes n’aiment pas faire confiance a la chance ou procéder par essai successifs en mesurant le pH de la maiche avec un papier pH et ajoutant des sels pour obtenir le bon PH. Il estime un moyen d’estimer le pH de votre maiche avant de commencer l’empattage et cette méthode sera développée dans la section suivante, mais d’abord voyons comment les grains affectent le pH de la maiche.

''However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.''

== 15.2 Balancing the Malts and Minerals ==

 When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.

Table 14 - Influence of Brewing WaterCity

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

From "American Handy Book", 2:790, Wahl-Henius, 1902

The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.

The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.

The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Beer Style
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

Pilsen - The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.

Dortmund - Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.

Vienna - The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.

Munich - Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.

London - The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.

Edinburgh - Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.

Burton-on-Trent - Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.

Dublin - Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.

== 15.3 Residual Alkalinity and Mash pH ==

 Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.

To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.

Historique: In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

Determiner le style de biere qui correspond le mieux a votre eau

1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)

 [[Image:15 3 3 1.gif]]

 

3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).

Determination de la quantite Calcium a ajouter pour faire baisser le pH de la maische

But what if you want to brew a much paler beer, like a Pilsener or a Helles? Then you will need to add more calcium to balance the alkalinity that your malt selection cannot.

1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.

 [[Image:15 3 3 2.gif]]

 

2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.

Determination de la quantite de Bicarbonate a ajouter pour augmenter le pH de la maische

 Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.

 [[Image:15 3 3 3.gif]]

 

1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:15 3 3 4.gif]] Figure 81: Full size nomograph for approximating your mash pH from your local water report. Click to bring up the full size pdf file.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download an Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4). 

 

== 15.4 Using Salts for Brewing Water Adjustment ==

 Brewing water can be adjusted (to a degree) by the addition of brewing salts. Unfortunately, the addition of salts to water is not a matter of 2 + 2 = 4, it tends to be 3.9 or 4.1, depending. Water chemistry can be complicated; the rules contain exceptions and thresholds where other rules and exceptions take over. 

Fortunately for most practical applications, you do not have to be that rigorous. You can add needed ions to your water with easily obtainable salts. To calculate how much to add, use the nomograph or another water chart to figure out what concentration is desired and then subtract your water's ion concentration to determine the difference. Next, consult Table 16 to see how much of an ion a particular salt can be expected to add. Don't forget to multiply the difference in concentration by the total volume of water you are working with.

Let's look back at the nomograph example where we determined that we needed 145 ppm of additional Calcium ion. Let's say that 4 gallons of water are used in the mash.

Choose a salt to use to add the needed calcium. Let's use gypsum. From Table 16, gypsum adds 61.5 ppm of Ca per gram of gypsum added to 1 gallon of water. Divide the 145 ppm by 61.5 to determine the number of grams of gypsum needed per gallon to make the desired concentration. 145/61.5 = 2.4 grams Next, multiply the number of grams per gallon by the number of gallons in the mash (4). 2.4 x 4 = 9.6 grams, which can be rounded to 10 grams. Unless you have a gram scale handy, you will want to convert that to teaspoons which is more convenient. There are 4 grams of gypsum per teaspoon, which gives us 10/4 = 2.5 teaspoons of gypsum to be added to the mash. Lastly, you need to realize how much sulfate this addition has made. 2.5 grams per gallon equals 368 ppm of sulfate added to the mash, which is a lot. In this case, it would probably be a good idea to use calcium chloride for half of the addition.

The following table provides information on the use and results of each salt's addition. Brewing salts should be used sparingly to make up for gross deficiencies or overabundance of ions. The concentrations given in Table 16 below are for 1 gram dissolved in 1 gallon of distilled water. Dissolution of 1 gram of a salt in your water will result in a different value due to your water's specific mineral content and pH. However, the results should be reasonably close. Please refer to Appendix F - Recommended Reading, for better discussions of water chemistry and brewing water adjustment than I can provide here.

Table 16 - Salts for Water Adjustment

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Brewing Saltand Common Name
| Concentration at 1 gram/gallon
| Grams per level teaspoon
| Effects
| Comments
|-
| Calcium Carbonate (CaCO3) a.k.a. Chalk
| 105 ppm Ca+2158 ppm CO3-2
| 1.8
| Raises pH
| Because of its limited solubility it is only effective when added directly to the mash. Use for making dark beers in areas of soft water. Use nomograph and monitor the mash pH with pH test papers to determine how much to add.
|-
| Calcium Sulfate (CaSO4*2 H2O) a.k.a. Gypsum
| 61.5 ppm Ca+2 147.4 ppm SO4-2
| 4.0
| Lowers pH
| Useful for adding calcium if the water is low in sulfate. Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Calcium Chloride (CaCl2*2H2O)
| 72 ppm Ca+2 127 ppm Cl-1
| 3.4
| Lowers pH
| Useful for adding Calcium if the water is low in chlorides.
|-
| Magnesium Sulfate (MgSO4*7H2O) a.k.a. Epsom Salt
| 26 ppm Mg+2 103 ppm SO4-2
| 4.5
| Lowers pH by a small amount.
| Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Sodium Bicarbonate (NaHCO3) a.k.a. Baking Soda
| 75 ppm Na+1 191 ppm HCO3-
| 4.4
| Raises pH by adding alkalinity.
| If your pH is too low and/or has low residual alkalinity, then you can add alkalinity. See procedure for calcium carbonate.
|}

 My final advice on the matter is that if you want to brew a pale beer and have water that is very high in carbonates and low in calcium, then your best bet is to use bottled water* from the store or to dilute your water with distilled water and add gypsum or calcium chloride to make up the calcium deficit. Watch your sulfate and chloride counts though. Mineral dilution with water is not as straightforward as it is with wort dilution, due to the various ion buffering effects, but it will be reasonably close. Good Luck!

*You should be able to get an analysis of the bottled water by calling the manufacturer. I have done this with a couple of different brands.

References Fix, G., Fix, L., An Analysis of Brewing Techniques, Brewers Publications, Boulder Colorado, 1997.

DeLange, AJ, personal communication, 1998.

Daniels, R., Designing Great Beers, Brewers Publications, Boulder Colorado, 1997.

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= Chapter 15 - Comprendre le pH de la maische =

== What Kind of Water Do I Need? ==

"What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?"

 This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.

The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.

 

== 15.1 Reading a Water Report ==

 To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. 

There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Recommended Level NS = No Standard ND = Not Detected

'''Calcium (Ca+2)''' Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.

'''Bicarbonate (HCO3-1) ''' Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.

Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:

 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas

 where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.

Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.

'''Sulfate (SO4-2)''' Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.

'''Sodium (Na+1) ''' Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chloride (Cl-1)''' Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm. The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.

'''Water Hardness, Alkalinity, and milliEquivalents''' Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.

Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.

(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3

These operations are summarized in the following table.

Table 13 - Conversion Factors for Ion Concentrations 

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 

'''Water pH''' You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks. 

Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.

However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.

== 15.2 Balancing the Malts and Minerals ==

 When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.

'''Table 14 - Influence of Brewing WaterCity'''

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

From "American Handy Book", 2:790, Wahl-Henius, 1902

The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.

The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.

The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Beer Style
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

'''Pilsen - '''The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.

'''Dortmund - '''Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.

'''Vienna - '''The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.

'''Munich - '''Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.

'''London - '''The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.

'''Edinburgh - '''Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.

'''Burton-on-Trent - '''Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.

'''Dublin -''' Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.

== 15.3 Residual Alkalinity and Mash pH ==

 Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.

To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.

'''Historique:''' In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

'''Determiner le style de biere qui correspond le mieux a votre eau'''

1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)

[[Image:F80.gif]]

 

3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).

'''Determination de la quantite Calcium a ajouter pour faire baisser le pH de la maische'''

But what if you want to brew a much paler beer, like a Pilsener or a Helles? Then you will need to add more calcium to balance the alkalinity that your malt selection cannot.

1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.

[[Image:F81.gif]]

 

2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.

Determination de la quantite de Bicarbonate a ajouter pour augmenter le pH de la maische

 Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.

[[Image:F82.gif]]

 

1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:F83.gif]] Figure 81: Full size nomograph for approximating your mash pH from your local water report. Click to bring up the full size pdf file.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download an Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4). 

 

== 15.4 Using Salts for Brewing Water Adjustment ==

 Brewing water can be adjusted (to a degree) by the addition of brewing salts. Unfortunately, the addition of salts to water is not a matter of 2 + 2 = 4, it tends to be 3.9 or 4.1, depending. Water chemistry can be complicated; the rules contain exceptions and thresholds where other rules and exceptions take over. 

Fortunately for most practical applications, you do not have to be that rigorous. You can add needed ions to your water with easily obtainable salts. To calculate how much to add, use the nomograph or another water chart to figure out what concentration is desired and then subtract your water's ion concentration to determine the difference. Next, consult Table 16 to see how much of an ion a particular salt can be expected to add. Don't forget to multiply the difference in concentration by the total volume of water you are working with.

Let's look back at the nomograph example where we determined that we needed 145 ppm of additional Calcium ion. Let's say that 4 gallons of water are used in the mash.

Choose a salt to use to add the needed calcium. Let's use gypsum. From Table 16, gypsum adds 61.5 ppm of Ca per gram of gypsum added to 1 gallon of water. Divide the 145 ppm by 61.5 to determine the number of grams of gypsum needed per gallon to make the desired concentration. 145/61.5 = 2.4 grams Next, multiply the number of grams per gallon by the number of gallons in the mash (4). 2.4 x 4 = 9.6 grams, which can be rounded to 10 grams. Unless you have a gram scale handy, you will want to convert that to teaspoons which is more convenient. There are 4 grams of gypsum per teaspoon, which gives us 10/4 = 2.5 teaspoons of gypsum to be added to the mash. Lastly, you need to realize how much sulfate this addition has made. 2.5 grams per gallon equals 368 ppm of sulfate added to the mash, which is a lot. In this case, it would probably be a good idea to use calcium chloride for half of the addition.

The following table provides information on the use and results of each salt's addition. Brewing salts should be used sparingly to make up for gross deficiencies or overabundance of ions. The concentrations given in Table 16 below are for 1 gram dissolved in 1 gallon of distilled water. Dissolution of 1 gram of a salt in your water will result in a different value due to your water's specific mineral content and pH. However, the results should be reasonably close. Please refer to Appendix F - Recommended Reading, for better discussions of water chemistry and brewing water adjustment than I can provide here.

'''Table 16 - Salts for Water Adjustment'''

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Brewing Saltand Common Name
| Concentration at 1 gram/gallon
| Grams per level teaspoon
| Effects
| Comments
|-
| Calcium Carbonate (CaCO3) a.k.a. Chalk
| 105 ppm Ca+2158 ppm CO3-2
| 1.8
| Raises pH
| Because of its limited solubility it is only effective when added directly to the mash. Use for making dark beers in areas of soft water. Use nomograph and monitor the mash pH with pH test papers to determine how much to add.
|-
| Calcium Sulfate (CaSO4*2 H2O) a.k.a. Gypsum
| 61.5 ppm Ca+2 147.4 ppm SO4-2
| 4.0
| Lowers pH
| Useful for adding calcium if the water is low in sulfate. Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Calcium Chloride (CaCl2*2H2O)
| 72 ppm Ca+2 127 ppm Cl-1
| 3.4
| Lowers pH
| Useful for adding Calcium if the water is low in chlorides.
|-
| Magnesium Sulfate (MgSO4*7H2O) a.k.a. Epsom Salt
| 26 ppm Mg+2 103 ppm SO4-2
| 4.5
| Lowers pH by a small amount.
| Can be used to add sulfate "crispness" to the hop bitterness.
|-
| Sodium Bicarbonate (NaHCO3) a.k.a. Baking Soda
| 75 ppm Na+1 191 ppm HCO3-
| 4.4
| Raises pH by adding alkalinity.
| If your pH is too low and/or has low residual alkalinity, then you can add alkalinity. See procedure for calcium carbonate.
|}

 My final advice on the matter is that if you want to brew a pale beer and have water that is very high in carbonates and low in calcium, then your best bet is to use bottled water* from the store or to dilute your water with distilled water and add gypsum or calcium chloride to make up the calcium deficit. Watch your sulfate and chloride counts though. Mineral dilution with water is not as straightforward as it is with wort dilution, due to the various ion buffering effects, but it will be reasonably close. Good Luck!

*You should be able to get an analysis of the bottled water by calling the manufacturer. I have done this with a couple of different brands.

References Fix, G., Fix, L., An Analysis of Brewing Techniques, Brewers Publications, Boulder Colorado, 1997.

DeLange, AJ, personal communication, 1998.

Daniels, R., Designing Great Beers, Brewers Publications, Boulder Colorado, 1997.

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-12T18:10:48Z

Belix :

= Chapter 15 - Comprendre le pH de la maische =

== What Kind of Water Do I Need? ==

"What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?"

 This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.

The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.

 

== 15.1 Reading a Water Report ==

 To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. 

There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Parametres
| Niveau maximum tolere(mg/L)
| moyenne(mg/L)
|-
| '''Primary Standards'''
|
|
|-
| Clarity
| .5
| .08
|-
| '''Microbiological'''
|
|
|-
| Total Coliform
| 5%
| .12%
|-
| Fecal Coliform
| (detection)
| 0
|-
| '''Organic Chemicals'''
|
|
|-
| Pesticides/PCBs
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Semi-Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| Volatile Organic Compounds
|
|
|-
| (various - JP)
| (various - JP)
| ND
|-
| '''Inorganic Chemicals (list edited - JP)'''
|
|
|-
| Arsenic
| .05
| .002
|-
| Cadmium
| .005
| ND
|-
| Copper
| (zero goal)
| ND
|-
| Fluoride
| 1.4-2.4
| .22
|-
| Lead
| (zero goal)
| ND
|-
| Mercury
| .002
| ND
|-
| Nitrate
| 10
| .21
|-
| Nitrite
| 1
| ND
|-
| Radionuclides
|
|
|-
| (various)
| (various - JP)
| (various - JP)
|-
| '''Secondary Standards - Aesthetic'''
|
|
|-
| Chloride
| *250
| 91
|-
| Color
| 15
| 3
|-
| Foaming Agents
| .5
| ND
|-
| Iron
| .3
| ND
|-
| Manganese
| .05
| ND
|-
| Odor Threshold
| 3
| 2
|-
| pH
| No Standard
| 8.04
|-
| Silver
| .1
| ND
|-
| Conductance (mmho/cm)
| *900
| 984
|-
| Sulfate
| *250
| 244
|-
| Total Dissolved Solids
| *500
| 611
|-
| Zinc
| 5
| ND
|-
| '''Additional Parameters'''
|
|
|-
| Alkalinity as CaCO3
| NS
| 114
|-
| Calcium
| NS
| 68
|-
| Hardness as CaCO3
| NS
| 283
|-
| Magnesium
| NS
| 27.5
|-
| Potassium
| NS
| 4.5
|-
| Sodium
| NS
| 96
|}

 

'''*'''= Recommended Level NS = No Standard ND = Not Detected

'''Calcium (Ca+2)''' Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.

'''Bicarbonate (HCO3-1) ''' Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.

Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:

 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas

 where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.

Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.

'''Sulfate (SO4-2)''' Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.

'''Sodium (Na+1) ''' Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chloride (Cl-1)''' Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm. The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.

'''Water Hardness, Alkalinity, and milliEquivalents''' Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.

Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.

(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3

These operations are summarized in the following table.

Table 13 - Conversion Factors for Ion Concentrations 

 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

 

'''Water pH''' You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks. 

Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.

However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.

== 15.2 Balancing the Malts and Minerals ==

 When you mash 100% base malt grist with distilled water, you will usually get a mash pH between 5.7-5.8. (Remember, the target is 5.1-5.5 pH.) The natural acidity of roasted specialty malt additions (e.g. caramel, chocolate, black) to the mash can have a large effect on the pH. Using a dark crystal or roasted malt as 20% of the grainbill will often bring the pH down by half a unit (.5 pH). In distilled water, 100% caramel malt would typically yield a mash pH of 4.5-4.8, chocolate malt 4.3-4.5, and black malt 4.0-4.2. The chemistry of the water determines how much of an effect each malt addition has. The best way to explain this is to describe two of the world's most famous beers and their brewing waters. The Pilsen region of the Czech Republic was the birthplace of the Pilsener style of beer. A Pils is a crisp, golden clear lager with a very clean hoppy taste. The water of Pilsen is very soft, free of most minerals and very low in bicarbonates. The brewers used an acid rest with this water to bring the pH down to the target mash range of 5.1 - 5.5 using only the pale lager malts.

'''Table 14 - Influence of Brewing WaterCity'''

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Ca+2
| Mg+2
| HCO3-1
| Cl-1
| Na+1
| SO4-2
|-
| Pilsen
| 10
| 3
| 3
| 4.3
| 4
| -
|-
| Dublin
| 119
| 4
| 319
| 19
| 12
| 53
|}

From "American Handy Book", 2:790, Wahl-Henius, 1902

The other beer to consider is Guinness, the famous stout from Ireland. The water of Ireland is high in bicarbonates (HCO3-1), and has a fair amount of calcium but not enough to balance the bicarbonate. This results in hard, alkaline water with a lot of buffering power. The high alkalinity of the water makes it difficult to produce light pale beers that are not harsh tasting. The water does not allow the pH of a 100% base malt mash to hit the target range of 5 - 5.8, it remains higher and this extracts harsh phenolic and tannin compounds from the grain husks. The lower pH of an optimum mash (5.2-5.5) normally prevents these compounds from appearing in the finished beer. But why is this region of the world renowned for producing outstanding dark beers?. The reason is the dark malt itself. The highly roasted black malts used to make Guinness add acidity to the mash. These malts match and counter the buffering capability of the carbonates in the water, lowering the mash pH into the target range.

The fact of the matter is that dark beer cannot be brewed in Pilsen, and light lagers can't be brewed in Dublin without adding the proper type and amount of buffering salts. Before you brew your first all-grain beer, you should get a water analysis from your local water utility and look at the mineral profile to establish which styles of beer can best be produced. The use of roasted malts such as Caramel, Chocolate, Black Patent, and the toasted malts such as Munich and Vienna, can be used successfully in areas where the water is alkaline (i.e., a pH greater than 7.5 and a carbonate level of more than 200 parts per million) to produce good mash conditions. If you live in an area where the water is very soft (like Pilsen), then you can add brewing salts to the mash and sparge water to help achieve the target pH. The next two sections of this chapter, Residual Alkalinity and Mash pH, and Using Salts for Brewing Water Adjustment, discuss how to do this.

The following table lists examples of classic beer styles and the mineral profile of the city that developed them. By looking at the city and its resulting style of beer, you will gain an appreciation for how malt chemistry and water chemistry interrelate. Descriptions of the region's beer styles are given below.

Table 15 - Water Profiles From Notable Brewing Cities

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Ville
| Calcium(Ca+2)
| Magnesium (Mg+2)
| Bicarbonate (HCO3-1)
| SO4-2
| Na+1
| Cl-1
| Beer Style
|-
| Pilsen
| 10
| 3
| 3
| 4
| 3
| 4
| Pilsener
|-
| Dortmund
| 225
| 40
| 220
| 120
| 60
| 60
| Export Lager
|-
| Vienna
| 163
| 68
| 243
| 216
| 8
| 39
| Vienna Lager
|-
| Munich
| 109
| 21
| 171
| 79
| 2
| 36
| Oktoberfest
|-
| London
| 52
| 32
| 104
| 32
| 86
| 34
| British Bitter
|-
| Edinburgh
| 100
| 18
| 160
| 105
| 20
| 45
| Scottish Ale
|-
| Burton
| 352
| 24
| 320
| 820
| 44
| 16
| India Pale Ale
|-
| Dublin
| 118
| 4
| 319
| 54
| 12
| 19
| Dry Stout
|}

 Sources Burton: "The Practical Brewer", p. 10, Dortmund Noonen, G., "New Brewing Lager Beer" Dublin "The Practical Brewer", p. 10, Edinburgh London "Fermentation Technology", p. 13, Westermann and Huige Munich Pilsen "American Handy Book", 2:790, Wahl-Henius, 1902 Vienna

'''Pilsen - '''The very low hardness and alkalinity allow the proper mash pH to be reached with only base malts, achieving the soft rich flavor of fresh bread. The lack of sulfate provides for a mellow hop bitterness that does not overpower the soft maltiness; noble hop aroma is emphasized.

'''Dortmund - '''Another city famous for pale lagers, Dortmund Export has less hop character than a Pilsner, with a more assertive malt character due to the higher levels of all minerals. The balance of the minerals is very similar to Vienna, but the beer is bolder, drier, and lighter in color.

'''Vienna - '''The water of this city is similar to Dortmund, but lacks the level of calcium to balance the carbonates, and lacks as well the sodium and chloride for flavor. Attempts to imitate Dortmund Export failed miserably until a percentage of toasted malt was added to balance the mash, and Vienna's famous red-amber lagers were born.

'''Munich - '''Although moderate in most minerals, alkalinity from carbonates is high. The smooth flavors of the dunkels, bocks and oktoberfests of the region show the success of using dark malts to balance the carbonates and acidify the mash. The relatively low sulfate content provides for a mellow hop bitterness that lets the malt flavor dominate.

'''London - '''The higher carbonate level dictated the use of more dark malts to balance the mash, but the chloride and high sodium content also smoothed the flavors out, resulting in the well-known ruby-dark porters and copper-colored pale ales.

'''Edinburgh - '''Think of misty Scottish evenings and you think of strong Scottish ale - dark ruby highlights, a sweet malty beer with a mellow hop finish. The water is similar to London's but with a bit more bicarbonate and sulfate, making a beer that can embrace a heavier malt body while using less hops to achieve balance.

'''Burton-on-Trent - '''Compared to London, the calcium and sulfate are remarkably high, but the hardness and alkalinity are balanced to nearly the degree of Pilsen. The high level of sulfate and low level of sodium produce an assertive, clean hop bitterness. Compared to the ales of London, Burton ales are paler, but much more bitter, although the bitterness is balanced by the higher alcohol and body of these ales.

'''Dublin -''' Famous for its stout, Dublin has the highest bicarbonate concentration of the cities of the British Isles, and Ireland embraces it with the darkest, maltiest beer in the world. The low levels of sodium, chloride and sulfate create an unobtrusive hop bitterness to properly balance all of the malt.

== 15.3 Residual Alkalinity and Mash pH ==

 Before you conduct your first mash, you probably want to be assured that it will probably work. Many people want to brew a dark stout or a light pilsener for their first all-grain beer, but these very dark and very light styles need the proper brewing water to achieve the desired mash pH. While there is not any surefire way to predict the exact pH, there are empirical methods and calculations that can put you in the ballpark, just like for hop IBU calculations. To estimate your base-malt-only mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from your local water utility report. Unfortunately, you rarely want to brew a base-malt-only beer.

To estimate your recipe mash pH, you will need the calcium, magnesium and alkalinity ion concentrations from the water report, plus the approximate color of the beer you are trying to brew.

'''Historique:''' In 1953, P. Kohlbach determined that 3.5 equivalents (Eq) of calcium reacts with malt phytin to release 1 equivalent of hydrogen ions which can "neutralize" 1 equivalent of water alkalinity. Magnesium, the other water hardness ion, also works but to a lesser extent, needing 7 equivalents to neutralize 1 equivalent of alkalinity. Alkalinity which is not neutralized is termed "residual alkalinity" (abbreviated RA). On a per volume basis, this can be expressed as: mEq/L RA = mEq/L Alkalinity - [(mEq/L Ca)/3.5 + (mEq/L Mg)/7] where mEq/L is defined as milliequivalents per liter.

This residual alkalinity will cause an all-base-malt mash to have a higher pH than is desirable (ie. >6.0), resulting in tannin extraction, etc. To counteract the RA, brewers in alkaline water areas like Dublin added dark roasted malts which have a natural acidity that brings the mash pH back into the right range (5.2-5.6). To help you determine what your RA is, and what your mash pH will probably be for a 100% base malt mash, I have put together the following nomograph that allows you to read the base-malt-mash-pH after marking-off your water's calcium, magnesium and alkalinity levels. To use the chart, you mark off the calcium and magnesium levels to determine an "effective" hardness (EH), then draw a line from that value through your alkalinity value to point to the RA and the approximate pH. The effective hardness is not the same as the "Total Hardness as CaCO3" you may see on your water report, it is a calculation of the effect that calcium and magnesium have on alkalinity.

After determining your RA and probable pH, the chart offers you two options: a) You can plan to brew a style of beer that approximately matches the color guide above your RA, or b) You can estimate an amount of calcium or bicarbonate to add to the brewing water to hit a targeted residual alkalinity, one that is more appropriate to the color of the style you want to brew. I will show you how this works in the following example.

'''Determiner le style de biere qui correspond le mieux a votre eau'''

1. A water report for Los Angeles, CA, states that the three ion concentrations are: Ca (ppm) = 70 Mg (ppm) = 30 Alkalinity = 120 ppm as CaCO3 2. Mark these values on the appropriate scales. (Denoted by red and green circles here.)

[[Image:F80.gif]]

3. Draw a line between the Ca and Mg values to determine the Effective Hardness. (Denoted by a red square.) 4. From the value for EH, draw a line through the Alkalinity value (green circle) to intersect the RA/pH scale. This is your estimated base-malt-mash pH of 5.8 (blue square). 5. Looking directly above the pH scale, the color guide shows a range of color which corresponds to most amber, red and brown ales and lagers. Most Pale Ale, Brown Ale and Porter recipes can be brewed with confidence. The amount of acidity in the specialty grains used in these styles should balance the residual alkalinity to achieve the proper mash pH (from 5.8 down to 5.2-5.6, depending on the darkness of the recipe).

'''Determination de la quantite Calcium a ajouter pour faire baisser le pH de la maische'''

But what if you want to brew a much paler beer, like a Pilsener or a Helles? Then you will need to add more calcium to balance the alkalinity that your malt selection cannot.

1. Go back to the nomograph and pick a point on the RA scale that is within the desired color range. In this example, I picked an RA value of -50.

[[Image:F81.gif]]

2. Draw a line from this RA value back through your Alkalinity value (from the water report), and determine your new EH value. 3. From the original Mg value from the report, draw a line through the new EH value and determine the new Ca value needed to produce this effective hardness. 4. Subtract the original Ca value from the new Ca value to determine how much calcium (per gallon) needs to be added. In this example, 145 ppm/gal. of additional calcium is needed. 5. The source for the calcium can be either calcium chloride or calcium sulfate (gypsum). See the following section for guidelines on just how much of these salts to add.

Determination de la quantite de Bicarbonate a ajouter pour augmenter le pH de la maische

 Likewise, you can determine how much additional alkalinity (HCO3) would be needed to brew a dark stout if you have water with low alkalinity.

[[Image:F82.gif]]

1. You determine your initial RA and base-malt-mash pH from your water report, and then determine your desired RA for the style you want to brew. In this example, I have selected an RA of 180 (base-malt-mash pH 6), which corresponds to a dark beer on the color guideline. 2. The difference is that this time you draw a line from the desired RA to the original EH, passing through a new Alkalinity. 3. Subtract the original alkalinity from the new alkalinity to determine the additional bicarbonate needed. The additional bicarbonate can be added by either using sodium bicarbonate (baking soda) or calcium carbonate. Using calcium carbonate additions would also affect the EH, causing you to re-evaluate the whole system, while using baking soda would also contribute high levels of sodium, which can contribute harsh flavors at high levels. You will probably want to add some of each to achieve the right bicarbonate level without adding too much sodium or calcium.

Note: The full size nomograph now contains an approximate numeric correlation to beer color (SRM scale). This is intended to better help you target a residual alkalinity level based on the color of the beer style, but it is an approximation. There is a lot of variation in the malt-acidity to malt-color relationship. [Oct.'06]

[[Image:F83.gif]] Figure 81: Full size nomograph for approximating your mash pH from your local water report. Click to bring up the full size pdf file.

New and Improved Residual Alkalinity Spreadsheets! (Oct. 2008)

Click Here to download an Excel spreadsheet that makes the same calculations (US units, Version 2.4).

Click Here to download an Excel spreadsheet that makes the calculations in metric. (SI units, Version 2.4).

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-12T17:54:13Z

Belix :

How to brew/Section 3/Chap 15 : Le pH pendant le brassage

2009-02-12T17:19:01Z

Belix : Nouvelle page : == What Kind of Water Do I Need? == "What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkali...

== What Kind of Water Do I Need? ==

"What kind of water do I need for all-grain brewing?" (you ask) Usually, the water should be of moderate hardness and low-to-moderate alkalinity, but it depends... "What do these terms mean? Depends on What?" "Where can I get this kind of water?" "What is my own water like?"

 This chapter is all about answering those questions. The answers will depend on what type of beer you want to brew and the mineral character of the water that you have to start with.

The term "hardness" refers to the amount of calcium and magnesium ions in the water. Hard water commonly causes scale on pipes. Water hardness is balanced to a large degree by water alkalinity. Alkaline water is high in bicarbonates. Water that has high alkalinity causes the mash pH to be higher than it would be normally. Using dark roasted malts in the mash can balance alkaline water to achieve the proper mash pH, and this concept will be explored later in this chapter.

 

== 15.1 Reading a Water Report ==

 To understand your water, you need to get a copy of your area's annual water analysis. Call the Public Works department at City Hall and ask for a copy, they will usually send you one free-of-charge. An example for Los Angeles is shown in Table 12. Water quality reports are primarily oriented to the safe drinking water laws regarding contaminants like pesticides, bacteria and toxic metals. As brewers, we are interested in the Secondary or Aesthetic Standards that have to do with taste and pH. 

There are several important ions to consider when evaluating brewing water. The principal ions are Calcium (Ca+2), Magnesium (Mg+2), Bicarbonate (HCO3-1) and Sulfate (SO4-2). Sodium (Na+1), Chloride (Cl-1) and Sulfate (SO4-2) can influence the taste of the water and beer, but do not affect the mash pH like the others. Ion concentrations in water are usually discussed as parts per million (ppm), which is equivalent to a milligram of a substance per liter of water (mg/l). Descriptions of these ions follow the water report.

Table 12 - Los Angeles Metropolitan Water District Quality Report (1996 data)

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* = Recommended Level NS = No Standard ND = Not Detected

'''Calcium (Ca+2)''' Atomic Weight = 40.0 Equivalent Weight = 20.0 Brewing Range = 50-150 ppm. Calcium is the principal ion that determines water hardness and has a +2 charge. As it is in our own bodies, calcium is instrumental to many yeast, enzyme, and protein reactions, both in the mash and in the boil. It promotes clarity, flavor, and stability in the finished beer. Calcium additions may be necessary to assure sufficient enzyme activity for some mashes in water that is low in calcium. Calcium that is matched by bicarbonates in water is referred to as "temporary hardness". Temporary hardness can be removed by boiling (see Bicarbonate). Calcium that is left behind after the temporary hardness has been removed is called "permanent hardness".

'''Magnesium (Mg+2) ''' Atomic Weight = 24.3 Equivalent Weight = 12.1 Brewing Range = 10-30 ppm. This ion behaves very similarly to Calcium in water, but is less efficacious. It also contributes to water hardness. Magnesium is an important yeast nutrient in small amounts (10 -20 ppm), but amounts greater than 50 ppm tend to give a sour-bitter taste to the beer. Levels higher than 125 ppm have a laxative and diuretic affect.

'''Bicarbonate (HCO3-1) ''' Molecular Weight = 61.0 Equivalent Weight = 61.0 Brewing Range = 0-50 ppm for pale, base-malt only beers. 50-150 ppm for amber colored, toasted malt beers, 150-250 ppm for dark, roasted malt beers. The carbonate family of ions are the big players in determining brewing water chemistry. Carbonate (CO3-2), is an alkaline ion, raising the pH, and neutralizing dark malt acidity. Its cousin, bicarbonate (HCO3-1), has half the buffering capability but actually dominates the chemistry of most brewing water supplies because it is the principal form for carbonates in water with a pH less than 8.4. Carbonate itself typically exists as less than 1% of the total carbonate/bicarbonate/carbonic acid species until the pH exceeds 8.4. There are two methods the homebrewer can use to bring the bicarbonate level down to the nominal 50 - 150 ppm range for most pale ales, or even lower for light lagers such as Pilsener. These methods are boiling, and dilution.

Carbonate can be precipitated (ppt) out as Calcium Carbonate (CaCO3) by aeration and boiling according to the following reaction:

 2HCO3-1 + Ca+2 + O2 gas --> CaCO3 (ppt) + H2O + CO2 gas

 where oxygen from aeration acts as a catalyst and the heat of boiling prevents the carbon dioxide from dissolving back into the water to create carbonic acid.

Dilution is the easiest method of producing low carbonate water. Use distilled water from the grocery store (often referred to as Purified Water for use in steam irons) in a 1:1 ratio, and you will effectively cut your bicarbonate levels in half, although there will be a minor difference due to buffering reactions. Bottom Line: if you want to make soft water from hard water (e.g. to brew a Pilsener), dilution with distilled water is the best route.

'''Sulfate (SO4-2)''' Molecular Weight = 96.0 Equivalent Weight = 48.0 Brewing Range = 50-150 ppm for normally bitter beers, 150-350 ppm for very bitter beers The sulfate ion also combines with Ca and Mg to contribute to permanent hardness. It accentuates hop bitterness, making the bitterness seem drier, more crisp. At concentrations over 400 ppm however, the resulting bitterness can become astringent and unpleasant, and at concentrations over 750 ppm, it can cause diarrhea. Sulfate is only weakly alkaline and does not contribute to the overall alkalinity of water.

'''Sodium (Na+1) ''' Atomic Weight = 22.9 Equivalent Weight = 22.9 Brewing Range = 0-150 ppm. Sodium can occur in very high levels, particularly if you use a salt-based (i.e. ion exchange) water softener at home. In general, you should never use softened water for mashing. You probably needed the calcium it replaced and you definitely don't need the high sodium levels. At levels of 70 - 150 ppm it rounds out the beer flavors, accentuating the sweetness of the malt. But above 200 ppm the beer will start to taste salty. The combination of sodium with a high concentration of sulfate ions will generate a very harsh bitterness. Therefore keep at least one or the other as low as possible, preferably the sodium.

'''Chloride (Cl-1)''' Atomic Weight = 35.4 Equivalent Weight = 35.4 Brewing Range = 0-250 ppm. The chloride ion also accentuates the flavor and fullness of beer. Concentrations above 300 ppm (from heavily chlorinated water or residual bleach sanitizer) can lead to mediciney flavors due to chlorophenol compounds.

'''Water Hardness, Alkalinity, and milliEquivalents''' Hardness and Alkalinity of water are often expressed "as CaCO3". Hardness-as referring to the cation concentration, and alkalinity-as referring to the anions i.e. bicarbonate. If your local water analysis does not list the bicarbonate ion concentration (ppm), nor "Alkalinity as CaCO3", to give you an idea of the water's buffering power to the mash pH, then you will need to call the water department and ask to speak to one of the engineers. They will have that information.

Calcium, and to a lesser extent magnesium, combine with bicarbonate to form chalk which is only slightly soluble in neutral pH (7.0) water. The total concentration of these two ions in water is termed "hardness" and is most noticeable as carbonate scale on plumbing. Water Hardness is often listed on municipal water data sheets as "Hardness as CaCO3" and is equal to the sum of the Ca and Mg concentrations in milliequivalents per liter (mEq/l) multiplied by 50 (the Equivalent Weight of CaCO3). An Equivalent is a mole of an ion with a charge, + or -, of 1. The Equivalent Weight of Ca+2 is half of its atomic weight of 40, i.e. 20. Therefore if you divide the concentration in ppm or mg/l of Ca+2 by 20, you have the number of milliequivalents per liter of Ca+2. Adding the number of milliequivalents of Calcium and Magnesium together and multiplying by 50 gives the hardness as milliequivalents per liter of CaCO3.

(Ca (ppm)/20 + Mg (ppm)/12.1) x 50 = Total Hardness as CaCO3

These operations are summarized in the following table.

Table 13 - Conversion Factors for Ion Concentrations 

{| cellspacing="1" cellpadding="1" width="600" border="1"
|-
| Pour obtenir
| a partir de
| Operation
|-
| Ca (mEq/l)
| Ca (ppm)
| division par 20
|-
| Mg (mEq/l)
| Mg (ppm)
| division par 12.1
|-
| HCO3 (mEq/l)
| HCO3 (ppm)
| division par 61
|-
| CaCO3 (mEq/l)
| CaCO3 (ppm)
| division par 50
|-
| Ca (ppm)
| Ca (mEq/l)
| multiplication par 20
|-
| Ca (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Ca (ppm)
| Ca Hardness as CaCO3
| Division par 50 puis multiplication par 20
|-
| Mg (ppm)
| Mg (mEq/l)
| Multiplication par 12.1
|-
| Mg (ppm)
| Total Hardness as CaCO3
| ''Impossible''
|-
| Mg (ppm)
| Mg Hardness as CaCO3
| Division par 50 puis multiplication par 12.1
|-
| HCO3 (ppm)
| Alkalinity as CaCO3
| Division par 50 puis multiplication par 61
|-
| Ca Hardness as CaCO3
| Ca (ppm)
| Division par 20 puis multiplication par 50
|-
| Mg Hardness as CaCO3
| Mg (ppm)
| Division par 12.1 et multiplication par 50
|-
| Total Hardness as CaCO3
| Ca as CaCO3 and Mg as CaCO3
| Additioner les
|-
| Alkalinity as CaCO3
| HCO3 (ppm)
| Division par 61 puis multiplication par 50
|}

'''Water pH''' You would think that the pH of the water is important but actually it is not. It is the pH of the mash that is important, and that number is dependent on all of the ions we have been discussing. In fact, the ion concentrations are not relevant by themselves and it is not until the water is combined with a specific grain bill that the overall pH is determined, and it is that pH which affects the activity of the mash enzymes and the propensity for the extraction of astringent tannins from the grain husks. 

Many brewers have made the mistake of trying to change the pH of their water with salts or acids to bring it to the mash pH range before adding the malts. You can do it that way if you have enough experience with a particular recipe to know what the mash pH will turn out to be; but it is like putting the cart before the horse. It is better to start the mash, check the pH with test paper and then make any additions you feel are necessary to bring the pH to the proper range. Most of the time adjustment won't be needed.

However, most people don't like to trust to luck or go through the trial and error of testing the mash pH with pH paper and adding salts to get the right pH. There is a way to estimate your mash pH before you start and this method is discussed in a section to follow, but first, let's look at how the grain bill affects the mash pH.