2000 Volume 62 Issue 5 Pages 104-109
Thin layer drying characteristics of rough rice, variety “HINOHIKARI”, were measured using a dynamic ventilator method. Air temperatures of 5, 10, 15 and 20°C, relative humidity in a range from 6.31% to 87.1%, and initial moisture content 23.5% d.b. were used to obtain moisture content data. Air humidity was controlled using the saturated salt solutions, and the variation of air temperature was about ±0.1°C for each test. Results revealed that 1) the rough rice with initial moisture content of 23.5% d.b. was dried in the second falling rate period, 2) sphere model was presented and quite good agreement was obtained between the experimental results and the model predictions, 3) the drying constant in second falling rate period depends on air temperature and humidity, 4) equilibrium moisture content of rough rice was measured and fitted with Chen-Clayton's equation, 5)the latent heat of vaporization of water in the grain was calculated.
