工业化酿造过程中酵母分泌蛋白酶A的规律及影响因素的研究

Study on the rules and influencing factors of yeast proteinase A secretory under industrial scale brewing

对啤酒工业化规模发酵过程中酵母分泌蛋白酶A的规律进行了探讨,对酵母代数及酵母贮存条件等因素对酵母分泌蛋白酶A的影响进行了研究,并对蛋白酶A活性不同的成品纯生啤酒的泡持值、泡沫活性蛋白含量及蛋白酶A活性进行了跟踪分析。结果表明:发酵过程中,蛋白酶A的活性呈上升趋势且接种酵母的蛋白酶A活性越高,与其对应的发酵液中蛋白酶A的活性越高,成品酒的泡沫稳定性越差。另外,随着酵母代数及贮存时间的增加,酵母分泌蛋白酶A的量增加。当酵母蛋白酶A活性控制在0.015U/m L以下且成品酒的初始蛋白酶A活性在15×10-5U/m L以下时,储存4个月的成品纯生啤酒的泡沫稳定性较好。

The secretory regularity of proteinase A The factors such as yeast generation and storage from yeast was investigated in industrial scale fermentation. conditions were studied to achieve their influencing extent of yeast proteinase A excretory,and the change of proteinase A activity,foam protein and head retention of draft beer with different initial proteinase A level during storage were tested in this study. The results showed that the activity of proteinase A would increase during fermentation,and the tendency was pronounced for fermenting worts while the generation of yeasts was increased. In addition, with the increase of storage period, the concentration of proteinase A excreted from yeast cells also increased. When the activity of proteinase A by yeast was below 0.015U/mL and the initial proteinase A activity in final product was less than 15×10^-5U/mL,the foam stability of draft beer would be better than others after 4 months.