高产胞外多糖嗜热链球菌的筛选及其直投式发酵剂的应用  

Screening of Streptococcus thermophilus with high-producing exopolysaccharide and application of directed vat set

作　　者：周晴晴 李理[1] 俞赟霞 李言郡[1] 余腾斐 张妍 陈苏 ZHOU Qingqing;LI Li;YU Yunxia;LI Yanjun;YU Tengfei;ZHANG Yan;CHEN Su(Key Laboratory of Food and Biological Engineering of Zhejiang Province,Hangzhou Wahaha Technology Co.Ltd.,Hangzhou Wahaha Group Co.Ltd.,Hangzhou 310018,China)

机构地区：[1]杭州娃哈哈集团有限公司杭州娃哈哈科技有限公司浙江省食品生物工程重点实验室,浙江杭州310018

出　　处：《食品与发酵工业》2022年第5期81-88,共8页Food and Fermentation Industries

基　　金：省级重点研发计划项目(2021C02001)。

摘　　要：从青海农家自制酥油样品中分离得到1株高产胞外多糖(exopolysaccharide, EPS)的菌株WHH3379,经形态学观察、生理生化实验和分子生物学实验鉴定为嗜热链球菌(Streptococcus thermophilus)。对该菌株的基础特性进行测定,评价其产EPS的抗氧化活性,并探索由其制备的直投式发酵剂在发酵乳中的应用。结果表明,嗜热链球菌WHH3379能够产生(526.58±2.91)mg/L的EPS,且EPS具有良好的抗氧化活性。同时,嗜热链球菌WHH3379表现出优良的生长特性以及耐酸耐胆盐特性,得到的发酵乳黏度高,组织状态好,后酸化平缓,拉丝长度为(28.85±1.24)cm,黏度为(5 486±2.25)mPa·s,酸度为(75.00±2.34)°T,活菌数为1.89×10^(8)CFU/mL。该研究可为开发出一种高产胞外多糖并具有益生功能的直投式发酵剂提供科学依据。A high-producing exopolysaccharide(EPS) strain WHH3379 was isolated from yak butter sample made by Qinghai farmhouse. The strain was identified as Streptococcus thermophilus through morphological observation, physiological and biochemical experiments and molecular biology analyses. The basic characteristics of the strain were determined, the antioxidant activity of EPS was evaluated, and the application of directed vat set in fermented milk was explored. The results showed that, S. thermophilus WHH3379 could produce(526.58±2.91) mg/L EPS, and EPS had good antioxidant activity. Moreover, S. thermophilus WHH3379 exhibited excellent growth characteristics, acid and bile salt resistance abilities. The obtained fermented milk had high viscosity, good tissue state and mild acidification, with the length of(28.85±1.24) cm, the acidity index of(75.00±2.34) °T, viscosity of(5 486±32.25) mPa·s and the viable count of 1.89×10^(8)CFU/mL. This research provides a scientific basis for the development of a direct vat set with high production of EPS and probiotic functions.

关 键 词：乳酸菌 嗜热链球菌 胞外多糖 分离纯化 抗氧化性 直投式发酵剂 应用 

分 类 号：TS201.3[轻工技术与工程—食品科学]