桔青霉在小麦中最大比生长速率的温度-水分活度复合模型的建立

Development of predictive model for combined effect of temperature and water activity on the maximum specific growth rate of Penicillium citrinum on wheat

为预测引起小麦储藏霉菌桔青霉的生长,在15～35℃温度下,0.70～0.96水分活度(Aw)下进行小麦储藏模拟实验,建立桔青霉P21的温度-水分活度预测模型。结果表明,桔青霉P21最适生长条件为温度25℃,Aw 0.85。一级生长模型中Boltsmann模型和Logistic模型拟合度都达到0.99。以Logistic模型拟合数据建立二级模型,采用平方根模型和Arrhenius,Davey模型拟合,Arrhenius,Davey模型能较好描述桔青霉P21最大比生长速率与温度、水分活度之间的对应关系,相关系数R达0.9440。

A full factorial design of five temperatures （15-35 ℃） and five water activity（Aw） values between 0.70 and 0.96 was used to investigate the growth of the Penicillium citrinum on wheat. The colony growth rates（u） and maximum colony diameter were estimated by fitting the Boltsmann model and the Logistic model. The isplates studied had optimum growth temperatures and Aw of approximately 25℃, 0.85. Subsequently, secondary models relating temperature and water activity combined, were developed and validated by using square root model and Arrhenius-Davey model. The R value of the Arrhenius-Davey model was 0.9440. Based on the validation criteria, the Arrhenius-Davey model is proved to be suitable for describing the combined effect of Aw and temperature.