即食凉拌菜中单增李斯特菌生长模型的建立

Predictive Modeling of Listeria monocytogenes Growth in Ready-to-Eat Dishes

为建立不同温度条件下即食凉拌菜中单增李斯特菌的生长模型,分离得到单增李斯特菌株,接种到即食凉拌菜中获得其在35℃的生长数据,结合ComBase数据库中单增李斯特菌在5、10、15、20、25℃的生长数据,选用Logistic模型为初级模型,并拟合得到最大比生长速率和生长迟滞期,分别建立Linear、Square Root和Ratkowsky模型,并进行数学检验。结果表明:Ratkowsky模型的评价结果优于其他两种模型,可以作为次级模型来对即食凉拌菜中单增李斯特菌的生长状况进行预测。

This study was designed to establish a model of the growth of Listeria monocytogenes in ready-to-eat dishes at different temperatures. An isolated strain of L. monocytogenes was inoculated to ready-to-eat dishes to obtain growth data at 35℃. Other data at 5, 10, 15, 20 ℃ and 25 ℃ were obtained from the ComBase database. Logistic model was selected as the primary model, which was fitted to achieve maximum growth rate （MGR） and lag phase （LP）, and the MGR and LP were used to establish a linear model, a square root model and a Ratkowsky model, respectively. The mathematical models were validated. The results showed that the Ratkowsky model was the best one to predict the growth of L. monocytogenes in ready-to-eat dishes. This study may provide a theoretical reference for quantitative microbial risk assessment ofL. monocytogenes in ready- to-eat dishes.