Calcium Hardness Ca and mg Temporary caco3 cacho3 and permanent ca s04

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1 Agenda Water and Style PH Water Chemistry Ca Mg Alkalinity Sodium Potassium Sulphate Chloride Congress mash Residual Alkalinity Brewing Cities Practical Water Treatment Water and Style Pale Dark Malty Bitter Differention in flights PH Power of Hydrogen 0-14 logarithmic scale most tap waters in the 8 range Ideal mash range ( at,mash temp) Tannins not extracted if ph<6 Acidify sparge water Use ro water to sparge Beer ph < 4 sharp acid perceived bitterness increased >4 effects mouth coating greater toasted and biscuit flavours noted >4.4 soapy and casutic Salt- neutral compound composed of ions Buffer-resists changes to ph when small amounts of acid or alkali are added Water Chemistry Calcium Hardness Ca and mg Temporary caco3 cacho3 and permanent ca s04

2 The mash contains a number of chemicals based on phosphorous, which are weak acidic buffers.. But the mash enzymes work best at lower ph's around 5.2. So we often must aid the acidification of the mash. Calcium reacts with the phosphates to form insoluble compounds which precipitate out of the mash. In addition, hydrogen ions are released in this process. Hydrogen ions (H+) are the defining constituent of acids, so we get acidification not only from removal of the buffering ("stabilizing") phosphates, but by the addition of H+ ions. So calcium is crucial to proper mash acidification flavour neutral except for its effects on Mg influence The lower ph improves ß-amylase activity and thus wort fermentability and extract. The optimum ph for ß-amylase activity is about 4 7. Wort produced from liquor containing no calcium has a ph in the order of , compared to values in the range of for worts produced from treated brewing liquor. The activity of the ß-amylase then is greatly enhanced by the addition of calcium, this enzyme increasing the production of maltose from Amylose, and thus making worts more fermentable. Calcium has a beneficial effect on the precipitation of wort proteins, both during mashing and during the boil Calcium ions protect the enzyme a-amylase from inhibition by heat. a-amylase is an endo enzyme, cleaving the internal 1,4 glucosidic links of amylopectin resulting in a rapid reduction in wort viscosity. The optimum temperature range for a-amylase activity is but the enzyme is rapidly destroyed at these temperatures. Calcium stabilises a-amylase to Calcium precipitates oxalates as insoluble calcium oxalate. This again occurs in both the mash tun and the copper. If oxalates are not removed they can cause hazes in finished beers and also contribute to the formation of beerstone in FV's, CT's and casks. Oxalates are also thought to promote gushing in certain beers, although this is not generally a problem to the micro brewer. The presence of calcium reduces colour formation in the copper. Calcium ions improve beer fining performance. Calcium ions encourage yeast flocculation, each divalent positively charged calcium ion attracting negatively charged yeast cells to form small aggregations.. Magnesium Brewing range ppm Magnesium is an essential element of brewing liquor because it is required by yeast as a co-factor for the production of certain enzymes required for the fermentation process. It is invariably formulated into liquor treatments at relatively low levels. However caution must be exercised for 3 reasons:

3 Excess magnesium can interfere with the reactions of calcium because its phosphates are more soluble 2. Above about 20 mgs/l magnesium can give beer a sour and bitter taste 3. In excess magnesium has a laxative effect Bicarbonate (Alkalinity) 0-50 ppm pale amber dark roasty Alkalinity is related to ph but is not a direct measure of it. However, it IS a direct measure of the "buffering" capacity of the solution, or its "resistance" to attempts to lower its ph. In other words, the higher the alkalinity, the more acid would be required to begin to change the ph. Two solutions with identical ph's but differing alkalinities will require different levels of acidification to lower the ph to a given number. Both Hardness and Alkalinity are often quoted to be "as CaCO3". This ion needs to be very closely controlled in order to achieve good beer. High levels of bicarbonate cause high ph values throughout the brewing process according to the equation: HCO3- + H+ «H2CO3 (r) CO2 + H2O It should be noted that bicarbonate ions are rather more effective at raising wort ph than calcium ions are at reducing it. The conversion of bicarbonate to carbonic acid is reversible until heat is applied, which drives off the carbon dioxide. This effectively removes the acidic hydrogen ion from the system by using it to form a stable water molecule. The wort ph therefore remains high and all the advantages derived from the presence of adequate calcium levels and reduced ph are lost. We therefore see the following: * Harsh after-tastes in the finished beer * Extract will be reduced due to lower ß-amylase activity * Poorer fermentation due to reduced FAN levels. * Reduced protein precipitation due to high ph * Worts and beer more prone to infection * Increased extract of undesirable materials in the sparge, notably silicates, polyphenols and tannins The net result of this is then to decrease beer stability and shelf life and to increase the likelihood of troublesome hazes. Colour will be darker, and flavour will be detrimentally affected. Hop utilisation will be increased, giving more bitter beers Sodium: Brewing Range = ppm contributes a salty taste at a concentration of 150 to 200 mg/l and may be harsh at levels greater than 250 mg/l. At lower levels (up to 100 mg/l) sodium ions can produce a sweetening effect in conjunction with chloride ions.

4 .. At levels of 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. Potassium: can be salty at concentrations greater than 500 mg/l. Beer is high in potassium which is extracted from malt but it is essentially flavour neutral at these levels. Potassium chloride can be considered as a source of chloride instead of sodium chloride if sodium levels are too high. Sulphate and Chloride - sulphate gives beer a drier, more bitter flavour, whilst chloride imparts palate fullness and to an extent sweetness. However what must be noted is that it is the ratio of the concentrations of these two ions that is significant, rather than simply the actual concentrations. A ratio of about 2:1 sulphate to chloride is about right for a bitter beer, and it makes little difference if the actual values are 500:250 or 350:175 mgs/l. Ratios of 1:2 sulphate:chloride are recommended for mild ales, whilst a ratio of 1:3 may give best results for stouts or porters. Congress Mash The following table is an interesting look a just what the grain brings to the beer in terms of minerals and ions. The figures relate to a beer made using distilled water i.e. water that has had all ion and mineral content removed. Congress mash- ph Wort (mg/l) Beer (mg/l) Na+ (Sodium) K+ (Potassium) Ca2+ (Calcium) Mg2+(Magnesium) Zn2+ (Zinc) Cu2+ (Copper) Fe3+ (Iron) Cl- (Chloride) 5 15 SO4 2- (Sulphate) 5 15 PO43- (Phosphate) Residual Alkalinity Determines mash and beer ph

5 Race car Hardness alkalinity- grain bill dark malts contribute more acidity- all malts are not equal Stout and pale ale example Table 15 - Water Profiles From Notable Brewing Cities S04 CL RATIO CA BICARB CA/BICARB RATIO NA RA PILSEN DORTMUND BURTON LONDON VIENNA EDINBURGH MUNICH TULSA DUBLIN 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 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. (high s04/cl ratio 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. Carb is relatively low?????

6 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. Highish s04/cl ratio 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. 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. Remove temporary hardness for munich helles 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 Practical Water Treatment Remove the chlorine/chloramines from your water. A carbon block water filter is the easiest way to accomplish this... This is also a good time to add any distilled/ro water. This may be the most important step as chlorine compounds can combine with phenols from the yeast or malt and creat horrific medicinal chlorophenols.- paty attention to filter throughput CAC03 not soluble in water low ph mash CaS04 water soluble accentuate hop CACL- mash soluble accentuate malt MGS04- soluble be careful NAHco3- accentuates rounness and sweetness Acid- Lactic- taste and higher levels, hydrochloric or phosphoric.