凉皮中金黄色葡萄球菌生长预测模型的建立

Establishment of Growth Predictive Model of Staphylococcus aureus in Liangpi

为了研究金黄色葡萄球菌在凉皮中的生长规律,通过测定5℃、10℃、15℃、20℃、25℃下金黄色葡萄球菌在凉皮中的生长数据,采用Baranyi模型、Modified Gompertz和Huang模型拟合金黄色葡萄球菌的生长曲线。比较3种模型的相关系数和参数,将一级模型得到的最大比生长速率(μmax)与迟滞期(λ)建立与温度相关的二级模型。实验表明,Modified Gompertz模型建立的一级模型的偏差因子(B_f)和准确因子(A_f)均在合理范围内。采用Modified Gompertz模型拟合的μmax和λ建立其与温度的平方根模型,拟合得到的R2为0.80和0.88,说明Modified Gompertz模型最适合拟合生长曲线,二级模型经方差分析显示方程显著,表明所建模型能有效预测金黄色葡萄球菌在凉皮中的生长情况。本研究为凉皮中金黄色葡萄球菌的定量风险评估提供理论依据。

The growth curve of Staphylococcus aureus was fitted based on the Baranyi model, modified Gompertz model and Huang model to investigate the growth of Staphylococcus aureus in a traditional food Liangpi by determining the growth data at 5 ℃, 10 ℃, 15 ℃, 20 ℃ and 25 ℃. The correlation coefficients and parameters of the three models were compared, and the maximum specific growth rate（μmax） and lag phase（λ） obtained by the primary model were used to establish a temperature-dependent secondary model. The results showed that the bias factor（Bf） and accuracy factor（Af） of the primary model established by the modified Gompertz model were within a reasonable range. The square root model of temperature was established by using μmax and λ fitted by the modified Gompertz model, and the fitting R-2 is 0.80 and 0.88, indicating that the Modified Gompertz model was most suitable for fitting growth curve. In addition, the variance analysis of the secondary model showed that the model could effectively predict the growth of S.aureus in Liangpi. This study provided theoretical basis for the quantitative risk assessment of S. aureus in Liangpi.