EQUILIBRIUM MOISTURE CONTENTS OF ROUGH RICE DRIED USING HIGH-TEMPERATURE, FLUIDIZED-BED CONDITIONS

Desorption isotherms of long-grain rough rice with initial moisture content of 20.6% (wet basis) and dried in a fluidized-bed system at temperatures ranging from 60°C to 90°C and relative humidities from 7% to 75% were measured. Rice sample mass and drying air conditions were recorded throughout the drying duration for each test until a steady-state mass was attained. The Page equation, with experimentally determined drying parameters, was used to describe the drying data. Equilibrium moisture contents were used to estimate empirical constants of the modified Chung-Pfost equation. The resulting modified Chung-Pfost equation described the experimental data with a root mean square error (RMSE) of 0.73 and a coefficient of determination (R2) of 0.94.

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