Hot air thin layer drying method was studied for red pepper, Capsicum annum var. longum as the whole and cut pod states, at various temperature and air velocities.
Drying curve of whole pod showed a settling down period followed by the first and second falling rate periods. By lowering the drying temperature, the first falling rate period approached to a constant rate one. Cut drying curve had simple falling rate period and also cut drying method could effectively shorten the drying time.
Drying rate constant, k, was varied with time for both the drying methods arid the plots of k vs. time in two methods suggested the different drying mechanisms. When an average k was taken as a constant value, the following equations; M-M_t/M_o-M_e= e^(-0.118t) and M-M_e/M_o-M_e=exp(-0.342t^(0.128)) were applicable for whole and cut drying, respectively.
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