Comparison of Protein Degradation as a Consequence of Germination Time and Temperature in Rye and Barley Malts

摘要

The influence of germination time and temperature on proteins and pro teolytic activity in barley and rye malts were investigated using response surface methodology as a statistical tool. Total nitrogen content was not affected by variations in germination conditions for either grain. In experi mental worts, soluble nitrogen significantly (P < 0.05) increased in malts for both grains as a consequence of longer germination periods, with rye malts having considerably higher soluble nitrogen contents than barley malts. High amounts of free amino nitrogen were measured in rye malts and in creased over the germination period. In barley malts, long germination pe riods and high germination temperatures significantly increased free amino nitrogen. In rye malts, only germination time affected proteolytic activity significantly. The molecular weight of the proteins was measured by cap illary electrophoresis. Long germination periods caused significant pro tein breakdown in both grains. In barley, breakdown was enhanced by ap plying high germination temperatures.