Energy consumption and mathematical modeling of microwave drying of potato slices

Abstract

In this research, drying characteristics and energy requirements for microwave drying of potato slices were reported at four microwave power densities, 5, 10, 15 and 20W/g. During the experiments, potato slices were dried to the final moisture content of 0.08 from 2.294(kgH₂O/kgdry matter).  The experimental data were fitted to six drying models: Linear, Lewis, Henderson and Pabis, Wang and Singh, Page, and Midilli et al. models. The models were compared using the coefficient of determination, root mean square error and reduced chi-square. The Midilli et al. model best described the drying curve of potato slices. The effective moisture diffusivity was determined by using Fick’s second law and was observed to lie between 0.025×10⁻⁸ and 3.05×10⁻⁸ m²/s for the potato samples. The minimum and the maximum energy requirements for drying of potato slices were also determined as 4.22 MJ/kgH₂O and 10.56 MJ/kgH₂O for 15 and 5 W/g, respectively.

Keywords: potato, drying, mathematical model, effective diffusivity, energy consumption