Drying characteristics and color changes of infrared drying eggplant

In order to obtain dehydrated products with high quality, infrared drying in eggplant slices were researched at different temperatures, sample thicknesses and heating distances. The drying characteristics and color changes of eggplant slices were studied using multiple regression analysis. Two quadratic polynomial equations were obtained to evaluate the effect of drying temperature, sample thickness and heating distance on drying time and total color difference. The correlation coefficients of the two quadratic polynomial equations were 0.9888 and 0.9703, respectively. The results indicated that appropriate drying parameters (drying temperature, sample thickness and heating distance) could improve drying rate and maintained the color of eggplant slices. Energy consumption of infrared drying was 2.48 MJ/kg with 1 kg water evaporated. Compared with hot air drying, the energy consumption was saved by 22.7%.