南京市零售生鲜鸡类食品中沙门氏菌的污染状况调查

目的 :对南京市零售市场上鸡类食品中的沙门氏菌进行定性、定量检测,以了解其沙门氏菌的污染状况。方法 :选取超市和农贸市场作为采样点,分别采用PCR方法和最可能数(most probable number,MPN)定量法对样品进行检测;运用@risk风险评估软件,用Cumulative分布拟合阴性和阳性样品中沙门氏菌的污染水平,用Discrete分布拟合所有样品中沙门氏菌的污染水平。结果:288份鸡类食品中沙门氏菌阳性率高达14.9%,6种不同鸡类食品中沙门氏菌阳性率无差异,农贸市场零售鸡类食品沙门氏菌的阳性率高于超市;在8个抽检月份中,6、7月份阳性率较高,分别为27.5%和20.0%。阴性样品中沙门氏菌的污染水平为0.009 MPN/g,阳性样品中沙门氏菌的污染水平为1.080 MPN/g,所有检测样品中沙门氏菌的平均污染水平为0.018MPN/g。结论 :南京市零售鸡类食品中沙门氏菌的污染状况不容忽视,未来应加强对沙门氏菌污染的定量监测。

Contamination status of Salmonella in retail raw chicken products of Nanjing

Objective:To monitor the Salmonella contamination status of commercial chicken products in Nanjing city through detecting Salmonella qualitatively and quantitatively. Methods:Retail chicken products were collected from supermarkets and farmers markets in different region of Nanjing city. Samples were examined by polymerase chain reaction (PCR) and most probable number (MPN) method. Cumulative distribution was used to fit the contamination level of the positive and negative samples,and Discrete distribution was used to all. Results:Of the total 288 chicken products,43 (14.9%) tested positive for Salmonella. In regard to the positive rate of Salmonella,no significant difference was observed among the six different samples. Prevalence of Salmonella in chicken products from farmers markets was higher than that from supermarkets. During the eight surveillance monthes,the top two contamination rate was detected in June and July,27.5% and 20.0% respectively . MPN value of negative samples was 0.009 MPN perg and that of positive samples was 1.080 MPN per g,0.018 MPN per g for the average. Conclusion:The overall pollution situation of Salmonella in retail raw chicken products of Nanjing had aroused public concern,enhanced quantitative monitoring of the Salmonella infection was needed.