摘要:
为了描述脉冲强光杀菌过程和预测杀菌效果,建立了脉冲强光对副溶血性弧菌的杀菌动力学模型。采用单次辐照剂量为67、92、113 mJ/cm2分别处理3.0%氯化钠体系中副溶血性弧菌0~25 s,考察其杀菌效果。选取Linear、Weibull和Log-logistic三种数学模型来拟合脉冲强光杀菌的动力学过程,以精确因子(Af)、偏差因子(Bf)、根平均方差(RMSE)和决定系数(R2)作为模型拟合度优劣评价指标。结果表明,当辐照距离为30 cm,单次辐照剂量为113 mJ/cm2处理时间为25 s时,副溶血性弧菌减少5.63 logCFU/mL,杀菌率为99.96%;Weibull模型和Log-logistic模型较Linear模型能更好的拟合脉冲强光处理副溶血性弧菌的杀菌曲线,Weibull模型能最好地拟合脉冲强光杀菌的动力学过程,且相较Log-logistic模型更简洁、灵活实用。
Abstract:
Pulsed light inactivation models of Vibrio parahaemolyticus were studied in order to describe and predict the inactive effects.In order to explore the inactivation effect of pulsed light on Vibrio parahaemolyticus in 3.0% sodium chloride system,the number of Vibrio parahaemolyticus were measured after pulsed light at various flash fluence leves(67,92,113 mJ/cm2) for 0~25 s,respectively.Linear,Weibull and Log-logistic models were used to describe the pulsed light inactivation model.Four criteria,accuracy fact (Af), bias factor(Bf), root mean square error (RMSE) and regression coefficients (R2) were used to compare the Linear,Weibull and Log-Logistict models,respectively.The results showed that when the irradiation distance was 30 cm and the fluence was 113 mJ/cm2 and treatment time was 25 s the Vibrio parahaemolyticus was reduced by 5.63 log CFU/mL, which the sterilization rate was 99.96%.Compared with Linear model,Weibull model and Log-logistic model could better fit the bactericidal curve of Vibrio parahaemolyticus treated by pulsed light.The Weibull model can best fit the dynamics process of pulsed light sterilization,which is simpler,more flexible and practical than the Log-logistic model.