一种中高黏度酸奶发酵剂的应用开发研究

Application Development Research of a Medium and High Viscosity Yoghurt Starter

为获得发酵时间短、后酸弱、产黏能力强、风味良好的中高黏度酸奶发酵剂,本文从润盈企业菌种库挑选7株唾液链球菌嗜热亚种菌株ST240、ST118、ST296、ST231、ST136、ST095和ST058,测试了这7株菌在乳品发酵过程中的发酵曲线、后酸化性能,以及对酸奶黏度、凝胶性和硬度的影响。结果表明,ST240产酸能力更强,后酸弱;ST240和ST118发酵酸奶黏度、凝胶强度及硬度中等。根据菌株特性,以ST240和ST118为主要菌株,通过调整菌株配比,考察不同方案发酵剂对乳品发酵过程中的发酵曲线、后酸化性能,以及对酸奶黏度、凝胶性和硬度的影响。最终方案五(ST240 100 UC、ST118 60 UC、ST058 40 UC)复配组合的酸奶发酵剂发酵速度快,风味良好,中高等黏度,适合于搅拌型酸奶的生产。

In order to obtain a medium and high viscosity yogurt starter with short fermentation time, weak acid after production, strong viscidity and good flavor, 7 strains of Streptococcus salivarius subsp. Thermophilus ST240, ST118,ST296, ST231, ST136, ST095 and ST058 were selected from the bacteria bank of Biogrowing Co., Ltd. The fermentation curve and post-acidification properties of these 7 strains during dairy fermentation were tested, as well as their effects on the viscosity, gelation and hardness of yogurt. The results showed that ST240 had stronger acid production capacity, and weaker acid after production. ST240 and ST118 fermented yogurt have medium viscosity, gel strength and hardness. According to the characteristics of the strains, ST240 and ST118 were selected as the main strains. By adjusting the ratio of strains,the influences of different starter cultures on the fermentation curve, post-acidification performance and the viscosity,gelation and hardness of yogurt during the fermentation process of dairy products were investigated. In the final scheme five(ST240 100 UC, ST118 60 UC, ST058 40 UC), the combination of yogurt starter has fast fermentation speed, good flavor,medium and high viscosity, which is suitable for the production of stirred yogurt.