Study on the buffering capacity of wort

Abstract

The effect of the buffering capacity of wort on a beer fermentation and the contribution of pH, phosphate, amino acids and organic acids to the buffering capacity of wort were studied. The beer pH depended on the buffering capacity of the corresponding wort and an increase in the buffering capacity of the wort could prolong the time of diacetyl conversion. The higher the wort pH was, the larger the wort buffering capacity. Phosphate was not an effective buffer at the pH of wort. Glutamic acid, aspartic acid and histidine gave weak contributions to the buffering capacity of wort, and the total contribution of these three amino acids was <0.1. Organic acids contributed substantially to the buffering capacity of the wort and the total contribution of organic acids to the buffering capacity of the wort was estimated to be about 0.31. The buffering capacity of lactic acid, citric acid, succinic acid, fumaric acid and pyruvic acid was 30, 50, 77, 15 and 9% of that of acetic acid, respectively, at the same mass concentration.