低酸环境对汾酒酿造的影响

Effect of low acid environment on fermentation of Fen-flover liquor

实验分析了酒醅不同初始pH值对发酵过程中pH值、酵母菌、好氧细菌及产酒量的影响。结果表明,初始pH值分别为4.0、5.0和6.0的酒醅在发酵过程中,0~4d的发酵初期pH值快速下降至4.0左右,直到发酵结束,大体保持在3.8~4.0的范围内,与对照相差不大。pH值为4.0的酒醅能明显促进酵母菌的生长,使酵母菌在发酵初期(乙酸处理酒醅4d,乳酸处理酒醅7d)明显大于其他初始pH值的酒醅。pH值的降低明显抑制了好氧细菌的生长繁殖,乙酸处理的酒醅中好氧细菌在4d^10d中表现出明显下降,15d时与对照样相似;乳酸处理的酒醅则抑菌效果略差。虽然初始pH值为4.0的酒醅有利于酵母菌的生长,却不利于酒精的形成与积累,而初始pH值为5.0的酒醅既有利于酵母菌生长又利于酒精的产生,是对发酵过程调控的一种有效手段。

Effect of initial pH value on fermenting grains pH, yeast, aerobic bacteria and yield during brewing process were analyzed. The results showed that the pH value of all of samples declined quickly during 0-4d, until the end of the fermentation remained at 3.8-4.0, little difference with the control. Fermenting grains with initial pH value 4.0 can significantly promote the growth of yeast, and was significantly greater than other initial pH value of the fermented grains in the early stage of fermentation. Fermenting grains with adjusted pH value significantly inhibited both aerobic bacterial growth and reproduction. Aerobic bacteria in fermenting grains treated by acetic acid decreased from 4d to 10d, while fermenting grains treated by lactate decreased from 7d to 15d and finally to be Similar to contrast. The initial pH value of 4.0 was good for yeast growth, but not conducive to the formation and accumulation of ethanol. Since fermented grains with initial pH value of 5.0 not only favor the growth of yeast, but also be conducive to the production of ethanol, conducting the pH of fermenting grains, and it would be an effective control method during brewing orocess.