高耐性酿酒酵母的筛选及其耐受性研究

优良的耐逆性菌株的添加能有效提高酱油生产效率和产品品质风味，该研究筛选出两株耐高温、耐高渗和耐高酸的酵母菌株用于酱油发酵。通过对酵母菌株高温热激之后稀释点板，对比各稀释度的菌落数量和形态，以及通过在高渗板和高酸板上各个菌的生长情况和在抗性培养基中菌的生长曲线测定来对比各菌株的耐受性。稀释点板实验以及生长曲线结果都显示，酿酒酵母L-19和L-38在55 ℃热激条件下以及在分别含有6%NaCl、0.6%乙酸和5%乳酸固体平板上菌落形态和大小都优于酱油酵母，而且在含有高盐和高酸的液体培养基中生长速率均高于酱油酵母。因此，成功筛选出两株具有高耐性的酿酒酵母。

Screening of high tolerance Saccharomyces cerevisiae and its tolerance

Adding excellent resistant strains can effectively improve the production efficiency of soy sauce and quality and flavor of products. Two strains of yeast resistant high temperature, hyperosmotic and high acid were screened and were used in the fermentation of soy sauce. The number and morphology of the colonies of different dilutions were compared by the dilution plate after the high temperature heat shock of the yeast, and the tolerance of each strain was compared by the growth on the hyperosmotic plate and the high acid plate and the growth curve determination in the resistance medium. The results of dilute point plate experiments and growth curve showed that the colony morphology and size of Saccharomyces cerevisiae L-19 and L-38 in the conditions of 55 ℃ heat shock and solid plate (containing 6% NaCl , 0.6% acetic acid and 5% lactic acid) were better than that of soy sauce yeast, and the growth rates of S. cerevisiae L-19 and L-38 in a liquid medium containing high salt and high acid were higher than that of soy sauce yeast. Therefore, two strains of yeast with high tolerance were successfully screened.