传统酵子中非酿酒酵母发酵馒头面团的特性研究

Characteristics of Non-Saccharomyces in Dough Fermentation for Steamed Bread Making

以从传统酵子中分离鉴定的异常威克汉姆酵母(Wickerhamomyces anomalus Y13)和德尔布有孢圆酵母(Torulaspora delbrueckii Y22)两株非酿酒酵母为材料,考察了两种酵母菌单独与混合接种条件下发酵小麦粉馒头面团的特性。结果表明:Y22在面团发酵的起始1 h内具有最快的发酵速度,1.5 h后与混合酵母菌群发酵的面团高度无显著差异,整个过程中Y13的发酵力都最低;Y22发酵面团中的还原糖含量随着发酵的进行逐渐增加,Y13与混合酵母发酵面团中还原糖含量在面团发酵的前8 h略有增大,而后则呈减少的趋势,说明糖含量不是发酵力的限制因素而与酵母本身特性相关;在面团发酵的前12 h,Y22发酵面团的pH显著低于Y13,说明其产酸水平高于Y13;混合酵母菌发酵小麦粉面团24 h后,Y13的细胞数量与其单独发酵时无显著差异,但Y22的细胞增长数量显著小于单独发酵面团的,说明混合酵母菌发酵体系下Y22的生长受到Y13的部分抑制。利用Y22与混合酵母菌群制作馒头的比容显著大于国标要求,具有应用于馒头生产的潜力。

In this study,the characteristics of two kinds of non-Saccharomyces yeast,Wickerhamomyces anomalus Y13 and Torulaspora delbrueckii Y22 isolated from Jiaozi,in dough fermentation in single and co-culture and their effects on steamed bread quality were studied. The results showed that Y22 had the highest fermentation speed in the initial 1 h of dough fermentation,and it had no significant difference with the dough fermented by co-culture after 1.5 h. The fermentation capacity of Y13 was the lowest in the whole process. The content of reducing sugar in the Y22 fermented dough increased gradually during the dough fermentation,and in the Y13 and the mixed yeast fermented dough,it increased in first 8 h and then decreased,indicating that the sugar content was not the limiting factor of the fermentation capacity of the yeast and was related to the yeast's own characteristics. The pH of dough inoculated with Y22 in the first 12 h was significantly lower than that of Y13,indicating that acid production level by Y22 was higher than that of Y13. After 24 h,the number of Y13 cells in the dough fermented by mixed yeast showed no difference from that by the single Y13 culture,but the cells of Y22 was significantly less than that of the single Y22 fermented dough,indicating that the growth of Y22 under the mixed yeast fermentation system was partially inhibited by Y13. The specific volume of steamed bread made by Y22 and mixed yeast group is significantly higher than that of national standard,which showed the potential of the non-Saccharomyces yeasts for steamed bread production.