冰鲜鸡肉中3种主要致病菌的共修复-增菌条件研究

Co-Recovery-Enrichment Conditions of Three Major Pathogenic Bacteria in Fresh Chicken Meat

研究冰鲜鸡肉中鼠伤寒沙门氏菌(S.typhimurium)、单增李斯特菌(L.monocytogenes)和大肠杆菌(E.coli)O157:H7的共修复-增菌条件。通过传统技术和PCR技术相结合的方法,研究肉鸡屠宰浸烫脱毛工艺对3种目标菌的热激损伤及共修复-增菌条件,并利用共修复-增菌结果,对生产线和超市的冰鲜鸡肉样品中3种目标菌的污染状况进行调查。结果表明:肉鸡屠宰浸烫脱毛工艺条件能使部分S.typhimurium、L.monocytogenes和E.coli O157:H7处于亚致死状态;TSB-YE培养基对热损伤S.typhimurium、L.monocytogenes和E.coli O157:H7的修复效果最好,且对前两种菌的修复时间为2h,对后一种菌的修复时间为4h;TSB-YE培养基在16h对3种致病菌的共增菌效果最好;运用共修复-增菌条件,对80份实际样品中的3种致病菌检出率分别为:S.typhimurium 22.5%(18/80)、L.monocytogenes 11.3%(9/80)和E.coli O157:H7 18.8%(15/80)。

In order to detect S.typhimurium,Listeria monocytogenes and E.coli O157：H7 in fresh chicken accurately and rapidly,traditional and multiple PCR methods were combined to explore co-recovery-enrichment conditions of heat-injured S.typhimurium,Listeria monocytogenes and E.coli O157：H7 in this study.The results showed that the scalding process could bring S.typhimurium,Listeria monocytogenes and E.coli O157： H7 into a sub-lethal state.TSB-YE was the best medium that could repair sub-lethal pathogenic bacteria.The recovery time of S.typhimurium and Listeria monocytogenes was 2 h,and that of E.coli O157：H7 was 4 h.After 16 h of enrichment,the best enrichment results were obtained for S.typhimurium,Listeria monocytogenes and E.coli O157： H7 in TSB-YE medium Under these co-recovery-enrichment conditions,the positive rates of S.typhimurium,Listeria monocytogenes and E.coli O157：H7 in 80 samples were 22.5%（18/80）,11.3%（9/80） and 18.8%（15/80）,respectively.