Authors: Dandan Zhao Kejing An Shenghua Ding Lijun Liu Zhiqiang Xu Zhengfu Wang
Publish Date: 2014/02/21
Volume: 7, Issue: 8, Pages: 2308-2318
Abstract
To display the advantages of twostage intermittent microwave coupled with hotair 60 °C drying IMAD different drying methods were compared The activation power density of samples dried by IMAD increased slightly and then rapidly as moisture content decreased Drying kinetics specific energy consumption and dried product quality such as colour rehydration ratio and α and βcarotene contents of carrot dried by IMAD under the optimum conditions were assessed and compared with those of carrot dried by hotair 60 °C drying hotair 60 °C drying followed by lowpower microwave 145 W drying highpower microwave 175 W drying followed by hotair 60 °C drying and highpower microwave 175 W drying followed by lowpower microwave 145 W drying The effective diffusivity increased gradually and then rapidly as moisture content decreased in all five drying processes The IMAD is a promising way for industrial application because it showed the lowest drying time with relatively low energy consumption and provided the best quality of final products with the best colour appearance highest rehydration ratio and highest α and βcarotene contents
Keywords: