山药热泵干燥特性及数学模型的研究

本文以新鲜山药为原料,研究其热泵干燥特性及数学模型。以干燥温度、切片厚度为因素,研究其对山药热泵干燥特性的影响,并通过SAS8.0软件对实验数据进行拟合得出山药热泵干燥模型,得到了山药热泵干燥的干燥特性曲线和干燥速率曲线。干燥温度越高、切片厚度越薄,山药的干燥速率越快,干燥时间越短。干燥温度对山药热泵干燥的速率有较大影响,而切片厚度对干燥速率的影响较小;山药热泵干燥符合Page模型,模型拟合效果很好,经验证,模型预测值与实验值比较吻合,能正确反应山药干燥规律,该模型可以用来描述山药热泵干燥过程变化过程。对热泵干燥山药产品的品质进行分析表明,与热风干燥相比,采用热泵干燥方式山药具有较好的复水性,色泽呈乳白色,感官品质良好。

Heat Pump Drying Characteristics and Mathematical Modeling of Chinese Yam

The heat pump drying characteristics and mathematical modeling of fresh Chinese yam were studied. The effects of different factors such as the temperature and thickness of yam on heat pump drying characteristics were investigated. Moreover, the obtained experimental data were processed using the SAS 8.0 software for mathematical modeling, and a heat pump drying curve and a drying rate curve were obtained. When the temperature was higher and the slice thickness was smaller, the drying speed was faster, and the drying time of Chinese yam was shorter. The drying rate was significantly affected by the temperature, but less affected by the slice thickness. The heat pump drying model for Chinese yam was in good agreement with the Page model. There was a good agreement between the predicted and experimental values, indicating that this model can describe and predict the moisture dynamics of Chinese yam during heat pump drying process. The quality of heat pump drying products was compared with that of hot air drying products. Chinese yam dried by the heat pump showed good rehydration behavior, with a milky white color and a good sensory quality.