超高静压协同中温对凝结芽孢杆菌芽孢灭活动力学规律的研究

研究了超高静压协同中温对凝结芽孢杆菌芽孢在磷酸缓冲液和牛奶(经超高温灭菌)中灭活的动力学规律, 并对超高静压的升压过程及相应的灭活效果进行了研究。结果表明, 升压过程对凝结芽孢杆菌芽孢灭活的影响不能忽略, 且随压力增加这种效果越强, 最高使其下降1.77个数量级; 凝结芽孢杆菌芽孢在牛奶中比在磷酸缓冲液中有更高的抗性; 在3种拟合模型(线性、Weibull和Log-logistic模型)中, 线性模型不适合模拟这些存活曲线, 而Log-logistic模型能更好地模拟这些存活曲线, 其次是Weibull模型。

Inactivation Kinetics of Bacillus coagulans Spore by the Combination of High Hydrostatic Pressure and Moderate Heat

The combination effect of high hydrostatic pressure and moderate heat on the inactivation kinetics of Bacillus coagulans spore in phosphate buffer and UHT (Ultra High Temperature) whole milk was investigated. The pressure come-up time and corresponding log-reduction of spore inactivation were considered during pressure-thermal treatment. Bacillus coagulans spore had a much higher resistance to pressure in UHT whole milk than in phosphate buffer. Survival data were modeled using the linear, Weibull and log-logistic models to obtain relevant kinetic parameters. The tailing phenomenon occurred in all survival curves, indicating the linear model was not adequate for describing these curves. The log-logistic model produced best fits to survival curves, following by Weibull model.