乳糖利用酵母菌的筛选及其特性初步研究  

Screening of Lactose Utilization Yeasts and Preliminary Study on Their Characteristics

作　　者：范瑞娟 石桂秋 FAN Rui-juan;SHI Gui-qiu(College of Biological Science ＆ Engineering,Ningxia Key Laboratory/of Microbial Resources Development and Applications in Special Environment,Key Laboratory of Fermentation Engineering and Biotechnology of State Ethnic Aiihirs Commission,North Minzu University,Yinchuan 750021,Ningxia,China)

机构地区：[1]北方民族大学生物科学与工程学院/宁夏特殊生境微生物资源开发与利用重点实验室/国家民委发酵酿造工程生物技术重点实验室,宁夏银川750021

出　　处：《食品研究与开发》2018年第24期26-33,共8页Food Research and Development

基　　金：宁夏特色微生物资源开发与利用创新团队科研项目(2018TSW01)

摘　　要：从水果表皮和生牛奶中筛选出可利用乳糖的酵母菌,并对其利用特征进行初步研究。结果共得到10株可利用乳糖的酵母菌,初步的降解试验表明,菌株B1、B2、H1和H2对牛奶中乳糖的利用效果最明显。对该4株酵母菌的生长曲线、最佳处理时间和接种量进行分析,结果表明,4株菌在20 h～26 h生长量达到最大,26小时后均可将牛奶中的乳糖含量从5%左右降至2.5%左右,与国家标准低乳糖牛奶的含量相当;菌株B1的最佳接种量为6%,B2、H1和H2的最佳接种量均为8%。对4株酵母菌处理后的纯牛奶的气味进行初步的感官评定,发现各菌株处理后的牛奶均有不同程度的香味。采用形态观察法结合18S rRNA基因序列比对的方法对该4株酵母菌进行鉴定,其中B1、B2分别为梅奇酵母菌属(Metschnikowia sp.)和威克汉姆酵母菌属(Wickerhamomyces sp.),H1和H2均为毕赤酵母菌属(Meyerozyma sp.)。Yeasts that can utilize lactose were isolated from fruit skins and raw milk, and their utilization characteristics were preliminarily studied. Totally 10 yeast strains that can utilize lactose were obtained in this study, preliminary degradation experiment indicated that, strains B 1, B2, H1 and H2 showed the most obvious effects on the utilization of lactose in milk. The growth curves, optimal treatment time and inoculum size of the 4 strains were analysed, the resuhs showed that the 4 strains reached the maximum growth during 20 h-26 h, and after 26 h, the lactose content in milk can be reduced from about 5 % to around 2.5 %, which was equivalent to the national standard low lactose milk; the optimal inoculum size tbr strain B1 was 6 %, and the optimal inoculum size tbr B2, H 1 and H2 was 8 %. A preliminary sensory evaluation of the odor of pure milk treated with the 4 strains was carried out, and it was found that the milk treated by each strain had ditterent degrees of aroma. Based on the morphological observation and sequence analysis of 18S rtlNA gene, B 1 and B2 were identifled as Metschnikowia sp. and Wickerhamomyces sp., respectively, Hland H2 were identified as Meyerozyma sp..

关 键 词：乳糖利用 生香酵母菌 低乳糖牛奶 

分 类 号：TS201.3[轻工技术与工程—食品科学]