高产乙酸乙酯酵母菌筛选及固态发酵应用研究

为提高清香型麸曲白酒中乙酸乙酯的含量，从已有菌株中筛选一株高产乙酸乙酯的酵母菌，将其应用于白酒固态发酵实验，并对其发酵条件进行研究。结果表明，筛选得到一株高产乙酸乙酯的酵母菌J-4，乙酸乙酯产量为1.38 g/L，经初步发酵实验表明，其最适固态发酵工艺条件为高粱粉与酒糟质量比1.0∶4.5，发酵时间7 d，酒醅入发酵容器后，以正常压力进行压醅（醅料密度为331.43 kg/m3），所得原酒中乙酸乙酯含量为1.31 g/L，出酒率为46.3%，均达到较高水平。进一步将酵母菌J-4应用于麸曲白酒酿造生产中，以不添加产酯酵母发酵为对照，采用相同生产工艺酿造白酒。结果表明，添加酵母菌J-4发酵生产原酒酒样中乙酸乙酯含量达1.07 g/L，比对照组增长50.7%，出酒率为45.3%，比对照组降低0.87%，原酒口感品质有明显改善。

Screening of yeast with high-yield of ethyl acetate and its application in the solid-state fermentation

For improving the content of ethyl acetate in light-flavor Fuqu Baijiu (Chinese liquor), a yeast strain with high-yield ethyl acetate was screened from existing strains and used in solid-state fermentation of Baijiu, and then the fermentation conditions were studied. The results showed that a dominate strain J-4 with high-yield ethyl acetate was screened, and the content of ethyl acetate in the culture solution reached 1.38 g/L. As a result of preliminary fermentation, it showed that the optimal solid-state fermentation condition was sorghum and vinasse proportion 1.0∶4.5, fermentation time 7 d, and the fermented grains were pressed under normal pressure after entering the fermentation vessel (the density of fermented grains was 331.43 kg/m3), the content of ethyl acetate in the base liquor was 1.31 g/L, the liquor yield was 46.3%, and both reached high levels. Taking the conventional fermentation as control, the fermentation of Fuqu Baijiu with yeast J-4 was carried out. The results demonstrated that the content of ethyl acetate in the base liquor produced with yeast J-4 was 1.07 g/L, increased 50.7% than the control, the liquor yield was 45.3%, which was 0.87% lower than the control, and the taste of base liquor was obviously improved.