2022—2024年昆明市巴氏杀菌乳中微生物污染现状及其菌株的鉴定

Microbial contamination status and strain identification of pasteurized milk in Kunming City from 2022 to 2024

中文关键词:  鲜奶吧  巴氏杀菌乳  微生物污染  鉴定分析  群落组成

英文关键词:fresh milk bar  pasteurized milk  microbial contamination  identification analysis  community composition

中文摘要:

      目的 研究昆明市鲜奶吧221批次巴氏杀菌乳中微生物的污染情况, 并鉴定分析污染菌株的群落结构。方法 依据国家标准规定的检验方法对巴氏杀菌乳中的菌落总数、大肠菌群、金黄色葡萄球菌、沙门氏菌开展检测分析, 通过VITEK 2 Compact全自动生化鉴定系统和RiboPrinter全自动微生物基因指纹鉴定系统对分离菌株开展鉴定分析。结果 检出不合格产品7批次, 其中, 菌落总数不合格1批次, 大肠菌群不合格6批次, 金黄色葡萄球菌不合格1批次。从所有阳性样品的菌落总数和大肠菌群平板上中分离鉴定出71株菌, 包括44种菌株, 来自18个菌属, 优势菌群为葡萄球菌属和芽孢杆菌属, 分别占比28.2% (20/71)、21.1% (15/71)。结论 巴氏杀菌乳存在不同程度的微生物污染, 应加强对昆明市鲜奶吧加工过程的卫生监管。

英文摘要:

      Objective To study the microbial contamination in 221 batches of pasteurized milk from Kunming fresh milk bar, and identify and analyze the community structure of the contaminated strains. Methods According to the inspection methods specified by national standards, the total number of colonies, coliform bacteria, Staphylococcus aureus, and Salmonella in pasteurized milk were detected and analyzed. The isolated strains were identified and analyzed using the VITEK 2 Compact fully automatic biochemical identification system and RiboPrinter fully automatic microbial gene fingerprint identification system. Results Seven batches of unqualified products were detected, including 1 batch with unqualified total bacterial count, 6 batches with unqualified coliforms, and 1 batch with unqualified Staphylococcus aureus. The 71 strains of bacteria, including 44 strains from 18 bacterial genera, were isolated and identified from the total number of bacterial colonies and Escherichia coli plates of all positive samples. The dominant bacterial groups were Staphylococcus and Bacillus, accounting for 28.2% (20/71) and 21.1% (15/71), respectively. Conclusion There are different degrees of microbial contamination in pasteurized milk, and the hygienic supervision of the processing of fresh milk bar in Kunming should be strengthened.