饮料中肠杆菌科细菌污染情况分析

国内不同地区几家企业生产的绿茶、还原乳、蜜橘饮料、奶茶中出现产品变质,胀瓶、产气等感官指标的变化,pH值均有所下降。主要污染菌经过16S rDNA序列比对鉴定为肠杆菌科Enterobacteriaceae细菌。蜜橘饮料和奶茶中分离到的3株典型污染菌,经过进一步的rpoB序列比对,鉴定为阴沟肠杆菌(Enterobacter cloacae)。肠杆菌科细菌不耐热,这些产品的污染属杀菌后的二次污染,该类微生物中有不少种类的菌对人体有害,或与致病菌有着亲密的亲缘关系。从生产线排查情况看,这类微生物的污染经由水(冲洗或冷凝水)或车间内湿润空气带入。

Analysis of Contamination of Enterbacteriaceae Bacteria in Drinks

Several different drinks(green tea drinks,milk,mandarin orange drinks,restituted-milk,milk tea)from various manufacturers in distinct areas were found deteriorated,with pH decrease,swell bottle,and gas production.The 11 typical bacteria were isolated and analyzed by 16S rDNA sequence,and identified as Enterobacteriaceae bacteria.Among them,3 isolates from mandarin orange drinks and milk tea were further identified as Enterobacter cloacae by rpoB sequence Balst.The bacterium of Enterobacteriaceae isn't heat-resistant.Those isolates were also proofed to have post after sterilization.Many species of Enterobacteriaceae are food-borne pathogens.On-the-spot inspection proofed that those bacteria polluted came from water(cooling water or flash water) or moist air.