摘要
利用热泵干燥装置探讨了热风温度和热风风速对荔枝果肉干燥水分比MR和干燥速率U的影响。结果表明:荔枝果肉薄层热风干燥是内部水分扩散控制的降速干燥过程。对9种常见食品薄层干燥模型进行试验数据非线性拟合,通过比较评价决定系数R2、卡方χ2和标准误差eRMSE以及试验验证,结果显示Page模型是描述荔枝果肉薄层热风干燥过程的最优模型。不同干燥条件下有效水分扩散系数Deff和活化能Ea的求解结果表明,有效水分扩散系数Deff随热风温度和风速的增加而变大,平均活化能Ea为29.939 kJ/mol。
The influences of drying temperature and hot air speed on the moisture ratio M R and the drying velocity U of litchi were studied by self-building heat pump drying device.The results showed that drying process of litchi occurred in the falling rate period,and the moisture transfer was controlled by internal diffusion.Nine different dynamic models were fitted nonlinearly by using the drying test data of litchi in the heat pump device.The results of comparing the values of the correlation coefficient R 2,the reduced chi-square χ 2 and the root mean square error e RMSE and the verification testing showed the Page model was the best suitable to descript the relationship of litchi moisture and drying time by hot air drying.The effective moisture diffusion coefficient D eff and the activation energy E a were also obtained by experiments under different conditions,the values of D eff would increase with the addition of drying temperature and hot air speed,the average value of E a was 29.939kJ/mol.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2012年第2期151-158,191,共9页
Transactions of the Chinese Society for Agricultural Machinery
基金
广东省茂名市科技计划资助项目(2007045)
上海市教育委员会重点学科建设项目(J50704)
关键词
荔枝果肉
热泵干燥
干燥特性
薄层干燥模型
Litchi flesh
Heat pump drying
Drying characteristics
Thin layer drying model
