In order to predict and monitor the growth of Salmonella in chilled beef,the predictive growth models for Salmonella under isothermal conditions and fluctuant conditions were respectively established.[Methods] Salmonella strains were inoculated to the surface of contamination-free chilled beef,then samples were placed at 0,4,7,10,15 and 20 ℃,and Salmonella kinetic growth curves were monitored during different storage periods.The primary predictive model of Salmonella was developed by the modified Gompertz equation or Linear equation.The secondary predictive model was established by the Ratkowsy-square root model.Meanwhile,the effectiveness of models was respectively validated under constant temperature and variable temperature conditions.The modified Gompertz equation could well describe the growth curves under 4 ～ 20 ℃ (R2 ＞ 0.99),while Linear equation was better at 0 ℃.Square root model could well describe the significant linear relationship of temperature with maximum rate and lag phase (R2 ＞ 0.96),which means the secondary predictive model of Salmonella were obtained as well.Comparing predictive data with experimental data at 9 ℃,12 ℃and fluctuant temperatures,bias factor (Bf) were 0.913,0.997,and 0.889,and accuracy factor (Af) were 1.118,1.019 and 1.147,respectively.The predictive growth models could predict the growth of Salmonella in chilled beef effectively.%建立了恒温条件下牛肉中沙门氏菌的生长动力学模型,准确掌握并及时预报沙门氏菌的生长情况,为冷却牛肉生产过程中该菌的控制提供有效的手段.将不同血清型的沙门氏菌混合菌株(以下简称沙门氏菌)接种到无污染的冷却牛肉表面,分别置于0、4、7、10、15和20℃恒温条件下贮藏并计数,采用Linear方程或修正的Gompertz方程拟合一级模型,并采用Ratkowsy平方根方程拟合二级模型.最后分别在恒温和波动温度下对模型进行验证.修正的Gompertz方程能较好地描述沙门氏菌在4～20℃贮藏条件下的生长动态(R2均大于0.99),而在0℃下则适用Linear方程拟合.采用平方根模型构建的沙门氏菌预测二级模型,表明温度对最大比生长速率(μmax)和迟滞期(λ)均呈现良好的线性关系(R2均大于0.96).用贮藏在9℃、12℃和波动温度下沙门氏菌的生长实验值进行验证,偏差度分别为0.913、0.997、0.889,准确度分别为1.118、1.019、1.147.该预测模型能有效预测4～ 20℃条件下沙门氏菌在冷却牛肉中的生长情况.
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