Effect of Microwave Energy on Vacuum Drying Kinetics of Alginate-Starch Gel

Abstract

Microwave energy drying under vacuum was investigated for alginate-starch hydrogel. Drying was conducted using 2450 MHz microwave energy at 25 mm Hg absolute pressure and different power levels; e.g., 300, 500, 700, 900, and 1100 watts. Drying was continued until final moisture content of the sample reached less than 1% wet basis. Moisture loss during drying was measured at 3-min intervals. Drying kinetics were used to describe both macroscopic and microscopic mechanisms of heat and mass transfer. Experimental drying kinetic data were fitted to a mathematical model. Experimental drying data points were fitted to an empirical model equation.

Keywords:

• Drying kinetics
• Hydrogel
• Mathematical model
• Microwave energy

ACKNOWLEDGEMENT

We acknowledge the Natural Sciences and Engineering Research Council of Canada (NSERC) for the Postdoctoral Fellowship and Discovery grant awarded to do this and related research.