馒头老酵子中酵母菌的分离鉴定及发酵特性分析

从馒头老酵子中分离纯化得到三株酵母菌(Y-1、Y-2、Y-3),以这三株酵母菌为研究对象,研究其发酵性能的差异。经ITS区序列分析后,鉴定Y-1与Y-2为酿酒酵母,Y-3为阿氏丝孢酵母。结果表明,Y-1与Y-2这两株酿酒酵母的生长能力比Y-3阿氏丝孢酵母强;Y-1的最适生长温度是28 ℃,Y-2的最适生长温度是28~32 ℃,Y-3的最适生长温度是36 ℃;Y-1最适生长pH为5.1~5.6,Y-2最适生长pH为5.1,Y-3最适生长pH为4.1;酵母菌发酵面团能力及液化力、糖化力、酯化力都显示Y-2>Y-1>Y-3。通过对三株酵母菌发酵性能的分析发现,酿酒酵母发酵性能优于阿氏丝孢酵母。

Identification and Fermentation Performance Analysis of Yeasts Isolated from Jiaozi

Three yeast strains(Y-1,Y-2 and Y-3)were isolated from the Jiaozi. The yeasts were used to study the differences in the fermentation performance. After the analysis of ITS sequence,Y-1 and Y-2 were identified as Saccharomyces cerevisiae and Y-3 was the Trichosporon asahii. The results showed that the growth of Y-1 and Y-2 were stronger than Y-3,the optimum growth temperature of the three yeast strains were 28,28~32 and 36 ℃,respectively. The optimum growth pH of the three yeast strains were 5.1~5.6,5.1 and 4.1,respectively. Fermentation ability,liquefaction power,saccharification power and esterification power all showed Y-2>Y-1>Y-3.Therefore,through the analysis of the fermentation performance of the three yeast strains,it was found that the performance of Saccharomyces cerevisiae was better than Trichosporon asahii.