基于乙醇质量分数的草莓果实腐烂指数预测模型

为应用电子鼻快速检测草莓物流过程中果实腐烂状况，建立了一种基于乙醇质量分数的果实腐烂指数预测模型。将草莓果实贮藏于不同温度（273、278、283、288、293和298 K）下，测定其腐烂指数和乙醇质量分数的变化。首先，基于Arrhenius动力学方程建立了草莓果实乙醇质量分数与贮藏时间和温度之间的动力学预测模型；其次，基于零级反应方程式建立了腐烂指数与贮藏时间和温度之间的动力学预测模型；最后，根据果实腐烂指数和乙醇质量分数变化的线性关系，进一步建立了基于乙醇质量分数的果实腐烂指数预测模型。在275、280、285、290、295和300 K贮藏温度下对上述3个预测模型进行验证，预测的相对误差（RE）分别为0.76%、5.89% 和7.08%，预测精度较高。将基于果实乙醇质量分数的腐烂指数预测模型与传统的腐烂指数动力学预测模型进行比较，发现二者的预测精度无显著差异。因此，基于乙醇质量分数的腐烂指数预测模型可以较好地预测在273～300 K贮藏温度下草莓果实的腐烂状况，从而为应用电子鼻无损检测果实品质提供理论依据。

Prediction model for decay index of strawberry fruit based on ethanol content

For the purpose of fast detection of fruit decay in strawberry fruit during postharvest distribution by gas sensor array, a prediction model for decay index based on ethanol content was developed in this study. Freshly harvested strawberries were stored at different temperatures (273, 278, 283, 288, 293 and 298 K). Changes in decay index and ethanol content of strawberry fruit were determined during storage. Firstly, a kinetic model of ethanol content with respect to storage time and temperature was developed based on the Arrhenius equation. Secondly, a kinetic model of decay index with respect to storage time and temperature was also developed based on the zero order equation. Finally, a prediction model for decay index based on ethanol content was further developed according to the linear relationship between decay index and ethanol content. The three models were then verified with the strawberry fruit stored at 275, 280, 285, 290, 295 and 300 K. The relative prediction errors were found to be 0.76%, 5.89%, 7.08% respectively, and the prediction accuracy was acceptable. There was no significant difference in prediction accuracy between the kinetic model of decay index and prediction model for decay index based on ethanol content. The results suggest that decay index of strawberry fruit can be accurately predicted at the storage temperature from 273 to 300 K by the prediction model for decay index based on ethanol content, which lays the foundation for the non-destructive real-time measurement of fruit quality using gas sensor array.