Effect of microwave drying on quality kinetics of okra

Abstract

The effects of microwave drying on quality attribute of okra were evaluated. Microwave power values show significant effect on moisture diffusivity, color, hardness and sensory attributes of dried okra. The total color change (Δ E) increased whereas L∗, a∗ and b∗ decreased with an increase in both power and time. The kinetics of L∗ and a∗ were well expressed by zero-order kinetic models, while b∗ and Δ E followed first-order kinetic models. Hardness was expressed by a first-order kinetic model. Sensory evaluation showed that okra dried at 800 W was most attractive in terms of color, texture, flavor and overall liking. Microwave drying at 800 W presented the shortest drying time with the least change in hardness, but the most change in color. Thus, high-power microwave drying potentially produces dried fruits and vegetables with minimum changes in hardness.