热泵干燥对黄金奇异果VC含量的影响及其干燥动力学模型拟合

目的：探究热泵干燥对黄金奇异果果片干燥特性的影响，并建立动力学模型。方法：采用不同的干燥温度（50℃、60℃、70℃），前处理方式（盐处理、热烫、切片厚度）干燥果片，通过测定和计算干燥特性指标，采用Page干燥模型对干燥过程进行拟合，构建干燥动力学方程。结果：干燥温度越高，果片的VC保留利率越低，在干燥温度恒定为50℃时，切片厚度5mm、0.3%（m/V）亚硫酸氢钠处理1h、热烫时间3s时的果片VC保留率最好。果片的水分比随干燥时间的延长呈现指数型下降趋势；切片厚度在5mm、热烫时间3s时，黄金奇异果片的Ea为25.7709kJ/mol，即热泵干燥黄金奇异果片的1mol水分所需的最低能量为25.7709kJ；黄金奇异果片的热泵干燥试验值与Page模型的拟合程度较好，模型的拟合优度R2=0.9990，卡方误差2=0.000086、方差分析的F值为37410.71、P＜0.01，说明试验值与拟合值间具有显著的相关性。结论：Page模型适合用于描述黄金奇异果片的热泵干燥过程，能较好为黄金奇异果果片的水分变化规律提供参考。

The effect of heat pump drying on the VC content of yellow flesh kiwifruit and its drying dynamics model fitting

Objective: To investigate the effect of heat pump drying on the drying characteristics of yellow flesh kiwifruit slices and establish a dynamic model. Method: Different drying temperatures (50 ℃, 60 ℃, 70 ℃) and pre-treatment methods (salt treatment, blanching, slice thickness) were used to dry fruit slices. By measuring and calculating drying characteristic indicators, the Page drying model was used to fit the drying process and construct a drying kinetics equation. Result: The higher the drying temperature, the lower the VC retention rate of fruit slices. When the drying temperature is constant at 50 ℃, the VC retention rate of fruit slices is the best when the slice thickness is 5mm, 0.3% (m/V) sodium bisulfite is treated for 1 hour, and the blanching time is 3 seconds. The moisture ratio of fruit slices shows an exponential downward trend with the extension of drying time; When the slice thickness is 5mm and the blanching time is 3s, the Ea of yellow flesh kiwifruit slices is 25.7709kJ/mol, which means the minimum energy required for 1 mol of water in the heat pump drying of yellow flesh kiwifruit slices is 25.7709kJ; The heat pump drying test values of yellow flesh kiwifruit slices showed a good fit with the Page model, with a goodness of fit of R2=0.9990 and a chi square error of 2=0.00086. The F-value of the analysis of variance was 37410.71, with P<0.01, indicating a significant correlation between the test values and the fitted values. Conclusion: The Page model is suitable for describing the heat pump drying process of yellow flesh kiwifruit slices and can provide a good reference for the moisture change law of yellow flesh kiwifruit slices.