凉瓜热风干燥动力学研究

Study on the drying dynamics of balsam pear

研究一定条件下风速与风温对经烫漂预处理的凉瓜薄层热风干燥过程的影响,拟合干燥曲线方程,并计算临界含水量、传热膜系数α与传质系数kH等动力学参数。结果表明:干燥方程符合Page模型;随风速增大,α与kH均增大,但风温对两者影响不大。在温度75℃、风机频率50 Hz的条件下干燥得到的凉瓜成品质地硬脆,呈暗绿或褐黄色,品质好。

The influence of the wind speed and temperature on the dry course of thin layer of the balsam pear by pretreatment with hot air under certain condition were studied.The dry curve equations were fitted the dynamics parameter such as the critical water content,heat transmission membrane coefficient α,and quality transmission coefficient kh were calculated.The results showed that the dry equation accords with the Page model.As the wind speed rises,α and kh were increased,but the wind temperature had a little effect on the two coefficient.Products dried at conditions of 50 Hz and 75℃ obtained good characteristics with good texture and color.