Mathematical modeling of thin layer microwave drying of Jaya fish (Aspidoparia jaya)

The effect of microwave power levels on the drying attributes of Jaya fish (Aspidoparia jaya) in a microwave dryer was investigated in this study. Microwave power levels of 100, 180, 300, and 450 W were used to dry 50 g of fish samples, and the drying kinetics were evaluated. Higher microwave power levels resulted in faster drying when increased from 100 to 450 W. The moisture ratio of fish during drying was calculated, and the data obtained were applied to 5 well known thin-layer mathematical models of drying, namely Approximate diffusion, Modified Henderson and Pabis, Two-Term, Logarithmic, and Midilli et al. model. Model constants and coefficients were calculated by nonlinear regression techniques. All the models were validated using statistical parameters namely; Coefficient of determination (R²), Root Mean Square Error (RMSE), Chi-square (χ²), and Standard Sum of Error (SSE). The Midilli et al. model gave an excellent fit to the experimental data of all the models evaluated. The effective diffusivity was calculated using Fick's diffusion equation, and the value varied from 1.40 × 10^-9 to 1.08 × 10^-8 m²/s. The activation energy and the diffusivity constant were found to be 4.656W/g and 1.22 × 10^-8 m²/s, respectively.