一株酒曲核心酵母的鉴定及产乙酸乙酯条件优化

Identification of a Yeast in Koji and Optimization of Ethyl Acetate Producing Conditions

通过形态学和分子生物学方法鉴定酒曲中一株高效产酯酵母菌株W-2,确定其为异常威克汉逊酵母。考察清香型白酒酿造过程中接种量、发酵时间和培养基对其乙酸乙酯产量的影响,通过单因素试验和响应面优化W-2菌株产乙酸乙酯的发酵条件。结果表明,最佳合成乙酸乙酯工艺条件为:发酵时间2d、含糖量41g/L、接种量4%,在此条件下该菌株发酵产生乙酸乙酯产量为(0.696±0.047)mg/mL;培养液中乙酸乙酯含量较高,香味浓郁,可用于生产乙酸乙酯含量高的酒曲。研究结果可为优质高含乙酸乙酯白酒的生产及规模化生产提供理论基础。

An unknown strain W-2 in koji was identified as Wickerhamomyces anomalus by molecular biology method.The inoculating amount,fermentation time and glucose content in the medium were used as independent variables,and the ethyl acetate content was used as the response value,the response surface analysis method was used to optimize the fermentation conditions of ethyl acetate produced by W-2 strain.The results showed that the optimum synthetic conditions of ethyl acetate were as follows:fermentation time 2 d,glucose content 41 g/L,inoculating amount 4%.Under these conditions,the yield of ethyl acetate produced by the strain was(0.696±0.047)mg/mL.The high content of ethyl acetate in medium canlead a rich aroma,which could be used to produce koji with high ethyl acetate content.This research results will provide a theoretical basis for the production and expansion of high quality ethyl acetate-containing liquor.