乳制品中肠炎沙门氏菌Salmonella enteritidis(CMCC 50041)生长预测模型的建立

Establishment of Predictive Model for Salmonella Enteritidis (CMCC50041) Growth in Different Dairy Products

为研究乳制品中肠炎沙门氏菌Salmonella enteritidis(CMCC 50041)的生长规律,选用3种乳制品(液体乳、奶油、乳酪)作为实验对象,比较了4、8、15、25、35 ℃条件下肠炎沙门氏菌的生长数据。利用5种常用的一级模型(Gompertz模型、Baranyi模型、Logistic模型、Richards模型和MMF模型)对实验数据进行拟合,通过比较相关系数和均方误差,确定最适一级模型为Gompertz模型。用平方根模型方程描述温度、pH值和水分活度与比生长速率和延滞期的关系,得到肠炎沙门氏菌生长二级模型,并通过偏差值Bf和准确值Af进行了外部验证。结果表明,构建的一级和二级生长模型能够较好地描述乳制品中肠炎沙门氏菌的生长动态,从而为有效监控乳制品中肠炎沙门氏菌污染提供一定的参考。

In order to predict the growth of Salmonella enteritidis (CMCC 50041) in the dairy,three kinds of dairy products (liquid milk,butter and cheese) were inoculated with Salmonella enteritidis,transferred for storage at 4,8,15,25,35 ℃.Five common primary models (Gompertz,Baranyi,Logistic,Richards and MMF) were applied to fit the growth curve for Salmonella enteritidis.The correlation coefficient and standard deviation were compared to identify Gompertz model as the best fitting model.Extended square-root models concerning growth kinetic parameters (maximum specific growth rate and lag period) of Salmonella enteritidis as a function of temperature,pH,water activity (a_(w)) and were developed to obtain the secondary growth model of Salmonella enteritidis.The bias value (Bf) and accuracy (Af) were calculated to evaluate the established models.The results showed that the secondary models could describe the growth of Salmonella enteritidis in these different dairy products,thus providing some reference for the effective monitoring of Salmonella enteritidis contamination in dairy products.