Analysis of Drying Kinetics and Mathematical Modelling of Peanut Pods using Sunlight, Hot Air, and Microwaves Drying Processes

This study analyzed the drying kinetics of peanut pods employing sun, hot air, and microwave drying techniques, and evaluated their mathematical modeling. The findings demonstrated that sun-drying decreased the moisture content from 26.47% to 8-10% over a duration surpassing 72 hours. Hot air drying at temperatures of 60°C, 80°C, and 100°C, commencing with an initial moisture content of 29.92%, necessitated 810 minutes, 360 minutes, and 660 minutes, respectively. Microwave drying, commencing with an initial moisture content of 23.01%, required 40 minutes, 45 minutes, and 60 minutes at belt velocities of 3 mm/s, 4.9 mm/s, and 6.2 mm/s, respectively, at 300 W. At 400 W, the durations were 24 minutes, 30 minutes, and 40 minutes, respectively. All drying kinetics curves exhibited decreasing rates characteristic of agro-food products. Mathematical modeling analysis identified the Midilli model as the most appropriate, succeeded by the Page, Henderson, and Pabis models, for characterizing moisture loss during the sun, hot air, and belt microwave drying of peanut pods.