复配大豆磷脂和蔗糖酯对面包酵母冷冻保护作用

以质量比为2∶1的大豆磷脂和蔗糖酯复配处理面包酵母,研究了其对酵母抗冻性的影响。结果表明,与未添加乳化剂组相比,酵母在-30℃含复配乳化剂质量分数为4 g/dL的YPD培养液中冷冻贮藏5 d,解冻并于30℃平板培养48 h,存活率提高了60%,酵母生长适应期缩短了10 h左右。将乳化剂处理酵母应用于冷冻面团体系,面团经-30℃冷冻贮藏60 d后醒发时间缩短,醒发体积增大。扫描电镜观察表明酵母与乳化剂呈聚集状,存在一定的交互作用。

Cryoprotective Role of Combined Emulsifiers with Soybean Lecithin and Sucrose Ester on Baker's Yeast

The cryoprotective role of emulsifiers combined with two molar soybean lecithin and one molar sucrose ester on baker’s yeast was examined in this study.The results showed that the survival ratio of yeast cultivated for 48 hours after frozen at-30 ℃ for 5 days in a culture medium with 4 g/dL combined emulsifers increased by 60% compared with that of the control group,and the adaptive phase shorten by 10 hours.The dough made from yeast dealed with emulsifiers after frozen at-30 ℃ for 60 days had a relatively stronger ability to leaven within a short time.The phenomenon of yeast congregated with enulsifiers,which was imaged by scanning electron microscope(SEM),indicated that there might be some interaction effects between the two substances.