The chemical compounds contained in the water exert a major influence on the shaping of the pH of the production wort, thus, they have a significant influence on the course and result of the mashing process.
The chemically active compounds include the salts which increase the pH of the mash and wort, thus negatively influencing the mashing process, and salts to lower the pH, the effect of which is beneficial in the beer production process.
The group of alkalizing compounds includes calcium carbonates, magnesium and sodium; for acidifying agents - sulphates and calcium and magnesium chlorides.
The main factor increasing the mash pil is the bicarbonate ion HCO3, the alkalizing effect of which is explained by the bonding of the hydrogen ion H +
The reaction of the carbonate ion with hydrogen reduces the concentration of hydrogen ions, thus increasing the pH.
Calcium and magnesium ions have the opposite effect, which lower the pH of the mash. It is theoretically explained this way, that during mashing, phosphorus compounds - salts and phosphoric acid - pass from the malt to the water. Phosphoric acid goes into solution dissociating.
The strongest alkalizing activity is shown by sodium bicarbonates, then magnesium, and the weakest calcium.
Strong calcium and magnesium salts, acids react with secondary potassium phosphate.
From the three calcium sulfate molecules, two primary phosphate molecules are formed. The tertiary calcium phosphate formed is insoluble and precipitates out of the solution lowering the mash pil.
The higher mash pH is one of the main reasons for the longer mash filtering process, which reduces the yield of the extract in the brewhouse.
Boiling the wort with a pH higher than 5,2 leads to an over-extraction of the tanning compounds of hops and those compounds contained in hops, which give the beer its "remaining" bitterness.
Regardless of the wort's pH, the deterioration of bitterness may be caused by the content of magnesium in the water. Magnesium reacts with the bitter substances of hops, causing the beer to taste sharp and unpleasant.
The lower pH of the wort leads to the proper biological stability and physicochemical stability of the beer.
The amount of precipitated protein compounds during the beer production process depends to a large extent on the concentration of hydrogen ions. At a wort pH of approx. 5,2 a good breakthrough is achieved and the amount of coagulating protein is reduced.
The ions contained in the water have a significant impact on the course of the beer fermentation and aging process, especially on the properties of yeast and the phenomena related to the natural clarification of beer.