pH IN MALTING AND BREWING-A REVIEW

Abstract

Variations in pH during malting, kilning, mashing, lautering, wort boiling and fermentation are reviewed. The fragmentary information available suggests that the pH of cold water extracts of barley falls during steeping, rises during germination and falls again during kilning. Brewing liquor, mashing method, addition of acid, and the nature of the malt influence the pH of unhopped wort, which falls by about 0·3 of a unit during boiling. Fermentation reduces the pH by a further unit yielding ales with pH values of about 3·8-4·2, or lagers of pH 4·2–4·8. Literature evidence does not suggest any obvious reason why ales and lagers should differ in pH.