三种原料对种曲微生物种类及变化影响研究

以早籼米、杂交粮和糯米为原料制备种曲，探讨其生产过程中微生物种类变化，并对分离菌株进行鉴定。结果表明，3种种曲中酵母菌、细菌、乳酸菌均呈上升趋势，早籼米和杂交粮种曲二烧时酵母菌最高，分别为4.7×109 CFU/g和6.2×109 CFU/g，糯米种曲三烧时酵母菌最高，为1.2×109 CFU/g；杂交粮种曲在二烧时细菌、乳酸菌最高，分别为2.4×1010 CFU/g和3.2×1010 CFU/g；早籼米、杂交粮、糯米种曲中霉菌先下降至二烧时最低，分别为3.8×104 CFU/g、7.1×103 CFU/g、7.5×103 CFU/g，之后上升至四烧时最高，分别为1.7×105 CFU/g、2.3×105 CFU/g、4.2×105 CFU/g。共分离纯化126株菌，其中酵母菌37株，主要为荚复膜孢酵母（Saccharomycopsis capsularis）、库德毕赤酵母（Pichia kudriavzevii）和三叶酵母（Saccharomyces mikatae）；霉菌29株，主要为横梗霉（Lichtheimia ramose）；细菌60株，主要有蔬菜芽孢杆菌（Bacillus oleronius）和乳酸片球菌（Pediococcus acidilactici）。

Effects of three raw materials on species and changes of microbe in seed Qu

Using seed Qu produced from three different raw materials (early indica rice, hybrid rice, and sticky rice) as experimental materials, the changes of microbial species during the production was discussed, and the isolated strains were identified. The results showed that the numbers of yeasts, bacteria and lactic acid bacteria in three kinds of seed Qu showed an upward trend. The number of yeasts in the seed Qu made of early indica rice and hybrid rice were the highest at the Ershao period, with 4.7×109 CFU/g and 6.2×109 CFU/g, respectively. The number of yeasts in sticky rice seed Qu was the highest in the Sanshao period, with 1.2×109 CFU/g; The numbers of bacteria and lactic acid bacteria in the hybrid rice seed Qu were the highest in the Ershao period, with 2.4×1010 CFU/g and 3.2×1010 CFU/g, respectively. The numbers of molds in three kinds of seed Qu continued to decline and were the lowest during the Ershao period. It was 3.8×104 CFU/g in early indica rice seed Qu, 7.1×103 CFU/g in hybrid rice seed Qu, and 7.5×103 CFU/g in sticky rice seed Qu, respectively. After that, it began to increase continuously. It reached a maximum of 1.7×105 CFU/g in early indica rice seed Qu, 2.3×105 CFU/g in hybrid rice seed Qu, and 4.2×105 CFU/g in sticky rice seed Qu. A total of 126 strains were purified, including 37 strains of yeasts, mainly Saccharomyces capsulatus, Pichia kudriavzevii and Saccharomyces mikatae. 29 strains of molds, mainly Lichtheimia ramosa, and 60 strains of bacteria, mainly Bacillus oleronius and Pediococcus acidilactici.