基于FSO值对生熟食品交叉污染中单增李斯特菌的危害识别

Hazard Identification of Listeria monocytogenes Cross-contamination from Raw to Cooked Food Based on Food Safety Objective Values

为定性分析生熟食品中单增李斯特菌在不同案板材质上的交叉污染,选定木制、塑料及不锈钢案板为材质研究对象,设置4种常见场景,并测定各案板材质不同场景下卤猪舌、案板与黄瓜中单增李斯特菌的污染水平(lg CFU/g)。同时,选择一级Baranyi模型修改式,二级主参数模型对黄瓜中单增李斯特菌的生长进行模拟。此外,根据食品安全目标(FSO)计算整个交叉污染过程的污染水平,并以即食食品中单增李斯特菌的FSO值2(lg CFU/g)为标准,与12种交叉污染情景(4种场景×3种材质)比较,并进行风险等级排序。结果表明:木质案板场景1(S1w)、塑料案板场景1(S1p)和不锈钢案板场景1(S1s)风险等级最高;场景2、3和4下,木质案板风险等级分别为2、3和3,高出塑料和不锈钢案板(3、4和4)一个风险等级。本研究表明对案板不进行任何清洗处理最易引发交叉污染,木质案板相较于其他2种案板材质的风险较大。

To qualitatively analyze the cross-contamination of Listeria monocytogenes from raw to cooked food on cutting boards of different materials, wooden, plastic, and stainless steel cutting boards were selected for this study. Four common scenarios were set up, and the contamination levels（lg CFU/g） of L. monocytogenes in marinated pig tongue, cucumber, and on cutting boards under different scenarios were measured. At the same time, the modified first-order Baranyi model and second order main parameter model were used to simulate the growth of L. monocytogenes in cucumber. Additionally, the contamination level of the whole cross-contamination process was calculated according to food safety objective（FSO） theory; 2 lg CFU/g was set as the standard value for the FSO of L. monocytogenes in ready-to-eat（RTE） foods and was compared with 12 cross-contamination scenarios, i.e., four scenarios using three materials, and the corresponding risks were ranked. The results showed that the wooden cutting board scenario 1（S1w）, plastic cutting board scenario 1（S1p） and stainless steel cutting board scenario 1（S1s） showed the highest risk. Under scenarios 2, 3, and 4, the risk levels of wooden cutting boards were 2, 3, and 3, respectively, which were one risk level higher than those of the cutting boards of the other two materials. In conclusion, this study showed that cross-contamination was most likely caused by the use of the cutting boards without any cleaning treatment, and the risk from the wooden cutting board was higher than that of the cutting boards of the other two materials.