Influence of convective and microwave drying on Algerian blood orange slices: Drying kinetics and characteristics, modeling, and drying energetics

Abstract

This research work aims to explore for the first time the effect of two drying processes on Algerian blood oranges (Citrus sinensis [L.] Osbeck): microwave(200, 400, 600, and 800 W) and convective(40°C, 60°C, 80°C, 100°C, and 120°C), on drying characteristics. The drying time was reduced from 90 min at 120°C (rate of 2.00 × 10−2 kgH2O/kg dm.min) to 13 min at 800 W microwave output (rate of 28.86 × 10−2 kgH2O/kg dm.min). The drying data were fitted to 38 models. Sledz et al. and Midilli and Kucuk models were found to be the best fit to describe drying kinetics for microwave and convective, respectively. The effective diffusivity ranged from 2.07 × 10−9 to 15.67 × 10−9 m2/s for microwave and from 0.07 × 10−9 to 1.97 × 10−9 m2/s for convective drying. The activation energy was estimated to be 8.871 W/g and 33.7 kJ/mol for microwave and convective respectively. The highest energy …