Modeling and optimization of microwave drying of rice

Abstract

The heat and mass transfer law of the microwave drying process of rice was studied by taking rice grains as the porous media. The effects of different microwave powers, initial temperatures, and intermittent time conditions on the rice drying characteristics were analyzed. Results showed that the change in the rice drying rate was nonlinear and directly related to the microwave power and initial temperature. The experimental data at different microwave powers, initial temperatures, and intermittent times were fitted through nonlinear regression. Determining coefficients were all greater than 0.9797. Sums of the squares of the deviation and root mean square errors were all less than 0.0042 and 0.0374 respectively. The method for establishing a nonlinear optimization experimental model for the microwave drying process of rice was also proposed. The reliability of the model was then confirmed by comparing the value obtained through the model with that obtained through the experiment. Novelty impact statement The moisture ratio models under different microwave power, initial temperature, and intermittent time in the paper have an ideal fitting to the experimental data of microwave drying of rice. The proposed model optimization method can accurately predict the moisture content in the process of rice drying.