山西老陈醋酿酒酵母菌共培养体系的研究

通过对山西老陈醋大曲的富集培养,筛选到9株高产乙醇或高产乙酸乙酯的酵母菌功能菌株,分别挑选高产乙醇和乙酸乙酯的酵母菌各1株(经分类鉴定,二者分别为酿酒酵母和异常汉逊酵母)进行共培养试验。通过L16(45)正交试验选择的最佳共培养条件为:麦芽汁培养基、pH值4.0、33℃8、0 r/min摇床培养。应用该共培养物进行了酿酒试验,乙醇和乙酸乙酯产量分别达到体积分数为5.93%和0.02%。以3%的共培养物加入到传统山西老陈醋的酿酒过程中,主要生产指标较传统工艺有显著提高,其乙醇产量提高14%,糖醇转化率提高18.6%,乙酸乙酯的含量提高了1倍。结果表明,通过构建功能菌共培养体系改善大曲微生物的群落结构,提高传统酿造产品的产量与质量是一条可行的途径。

Study on the Mixed-culture System of Yeasts in Shanxi Overmature Vinegar

9 strains of high alcohol-producing or high ethyl acetate-producing yeasts were isolated from koji of Shanxi overmature vinegar at different temperatures.One high alcohol-producing yeast Nz19.3 and one high ethyl acetate-producing yeast Nz9.8 were identified as Saccharomyces cerevisiae and Hansenula anomala,respectively.Then the optimal mixed-culture conditions of Nz9.8 and Nz19.3 were studied by L_(16)(4~5) orthogonal design,and the results were as following : wort zymotic medium,pH 4.0,33℃,rotate speed 80 r/min using a shaker.B using the mixed-culture system,It is seen that the concentration of alcohol and ethyl acetate was 5.93% and 0.02%,respectively.When the mixed-culture system was used to the traditional technology of Shanxi overmature vinegar with 3% inoculum,the yield of alcohol was increased by 14%,the conversion rate of alcohol to sugar was increased by 18.6%,and the content of ethyl acetate was doubled.The result shows that the mixed-culture system of yeasts can optimize microbial community structure,and can increase the yield and the quality of Shanxi overmature vinegar.