金昌市9类即食食品单核细胞增生李斯特菌监测分析

Monitoring and analysis on Listeria monocytogenes in nine kinds of instant food in Jinchang City

目的了解金昌市即食食品中单核细胞增生李斯特菌的污染状况及分布,并确定高危即食食品的种类。方法按国家食品安全风险评估中心建立的《国家食品污染物和有害因素风险工作手册》中食源性致病菌监测部分操作。于2011—2014年在金昌市农贸市场、超市、餐馆、便利店等采样并监测9大类食品,包括冷冻饮品、凉拌菜、地方特色食品、即食非发酵豆制品、熟肉制品、熟制米面制品、焙烤糕点饼干、学生餐、生食蔬菜共计1 033份。结果 1 033份样品中,有25份检出单核细胞增生李斯特菌（25株）,总检出率为2.42%。焙烤糕点饼干、学生餐未检出,生食蔬菜检出率最高（10.0%）,其次是冷冻饮品（6.48%）、凉拌菜（3.23%）、即食非发酵豆制品（1.74%）、地方特色食品（1.43%）、熟制米面制品（0.83%）、熟肉制品（0.8%）。不同季节检出率差异无统计学意义。单核细胞增生李斯特菌定量检测,菌落数在0.3~10 MPN/g占73.68%,10~100 MPN/g占26.32%。结论金昌市即食食品中单核细胞增生李斯特菌的污染严重,监管部门应加强食品销售行业的卫生监管,严格控制生食蔬菜、冷冻饮品、凉拌菜的污染,确保食品安全。

[Objective]To understand the contamination status and distribution of Listeria monocytogenes in instant food in Jinchang City,identify the types of high-risk food.[Methods]The surveillance of food borne pathogens was performed according to the National food contamination and risk factors handbook issued by the National Food Safety Risk Assessment Center.Totally 1 033 samples of instant food were collected from agricultural markets,supermarkets,restaurants,and convenience stores in Jinchang City from 2011-2014,including frozen drinks,salad,local specialty food,instant non-fermented soybean products,cooked meat products,cooked rice flour products,baked cakes/cookies,student meal,and raw vegetables.[Results]25 strains of Listeria monocytogenes were detected in 25 of 1 033 food samples,with the total detection rate of 2.42%.Listeria monocytogenes was not found in baked cakes/cookies and student meal.The detection rate in raw vegetables was the highest（6.48%）,followed by frozen drinks（6.48%）,salad（3.23%）,instant non-fermented soybean products（1.74%）,local specialty food（1.43%）,cooked rice flour products（0.83%）,and cooked meat products（0.8%）.The difference in detection rate was not statistically significant in different seasons.The quantitative detection results showed that the samples with colony forming units of 0.3-10 MPN/g accounted for 73.68%,and those with colony forming units of 10-100 MPN/g accounted for 26.32%.[Conclusion]The contamination status of Listeria monocytogenes in instant food is serious in Jinchang City.The management department should strengthen the health regulation of food sales industry,and strictly control the contamination in raw vegetables,frozen drinks,and salad,to ensure the food safety.