Drying kinetics and energy efficiency of microwave-dried lemon slices

Abstract

In the current study, lemon slices were dried at various microwave powers (120, 350, 460, 600, and 700 W) to determine drying characteristics and energy efficiency. Drying rate and time were significantly affected by the increase in microwave power. The lowest and highest drying times were 8 and 54 minutes at 700 and 120 W, respectively. As microwave power increased, drying rate increased, and drying time decreased. Besides, the most suitable model to describe microwave drying curves of the lemon slice was obtained as the Page model. The values of Deff of the dried lemon slices were calculated between 3.61x10-9 and 3.41x10-8 m2s-1. The Ea of the lemon slices drying, calculated using Deff, and the rate constant obtained from the Page model were 4.39 Wg-1 and 6.04 Wg-1, respectively. Additionally, the higher the cumulative energy efficiency, the lower the specific energy consumption. The lowest specific energy consumption and the highest energy efficiency were calculated at 460 W. The 460 W drying power was the best power with 11 min of drying time, the highest energy efficiency, and the lowest specific energy consumption.

Keywords

• lemon slices
• drying characteristics
• microwave drying
• effective diffusion
• energy efficiency