源于中高温大曲的米根霉制备米曲工艺优化及应用

Optimization and application of Miqu prepared by Rhizopus oryzae from medium-high temperature Daqu

目的:提高大曲白酒的出酒率。方法:从中高温大曲中筛选出高产糖化酶的菌株,将该菌株制作成米曲并应用至大曲白酒的酿造中,测定出酒率。结果:分离得到一株高产糖化酶菌株M-1,鉴定结果为米根霉(Rhizopus oryzae)。用该菌株制备成米曲的最优工艺条件为m_(麸皮)∶m_(米粉)为2∶8、米曲含水量45%、培养时间72 h、干燥温度40℃,此时米曲糖化酶活力高达864.50 U/g。当M-1米曲添加量为粮食质量的2%时,白酒出酒率提高至43.17%。结论:建立了一种将米根霉制备成米曲来提高中高温大曲糖化酶活力的方法。

Objective:A microbial enhancer with high-yield glucoamylase was developed from medium-high temperature Daqu and applied to the brewing of Daqu Baijiu for the yield increasing.Methods:Strains with high yield of glucoamylase was isolated from medium-high temperature Daqu and used to make Miqu.Miqu was employed as an enhanced starter in the brewing of Daqu Baijiu,and the yield of Baijiu were tested.Results:A strain M-1 with higher glucoamylase production was isolated and identified as Rhizopus oryzae.The results of the optimized conditions for Miqu making was as follows:bran and rice(2∶8),moisture content 45%,incubation time 72 h,drying temperature 40℃.Under the control of these conditions,the glucoamylase activity of Miqu is as high as 864.50 U/g.When appling the Miqu to the brewing of Daqu Baijiu,the results showed that when the addition amount of by,and the yield increased to 43.17%with the addition of 2%(weight of grain)M-1 Miqu.Conclusion:This study established a method for preparing Miqu from Rhizopus oryzae to improve the glucoamylase activity of medium-high temperature Daqu.