Intermittent Microwave Drying of Litchi: Drying Kinetics and Quality Formation in Color Difference

摘要

In order to reveal the characteristics of thermal transmission and drying quality on the litchi's multilayer structure, the peel and flesh that separated from fresh fruit were dried with the whole fruit by microwave radiation in three kinds of tempering intermittent HT0101, HTO505 and HT1010. Their characteristics of dehydration and the changes of color difference in drying process were compared. The results showed that microwave drying had influences on the capability of dehydration and the quality of color difference in different interval. The influence of HTO505 was more significant, while the other two conditions, in which there were only a small amplitude of cross and fluctuation, were approximate. In the same conditions of microwave drying, the capability of dehydration of peel and flesh separated was better than that of whole fruit, and the dehydration speed of peel was the fastest. As to color difference, the changes of peel and whole fruit were smaller and much easily to tend to stable. The change of the color difference on the flesh was obvious and finally tended to stable. The further research still needed the further study on biochemical effect during the transformation of quality.