Effects of different temperature field responses on postharvest storage quality of Cucurbita pepo L.

The present study was used to investigate the effect of heat-transfer process on the chilling resistance of cold-sensitive fruits during heat shock treatments,Cucurbita pepo L. as a typical cold sensitive fruits and vegetables,it was sensitive to low temperature,and easily suffer from chilling injure for unsuitable cold storage. Therefore,a three-dimensional numerical model was established to simulate the heat-transfer process of Cucurbita pepo L. during heat shock treatment,the heat transfer laws and temperature dynamic response processes of Cucurbita pepo L. during heat treatment were studied,the hot air at 40℃ was used as heat treatment medium,the effects of processing time of 0.5,1,2 and 4 h on the fresh-keeping of Cucurbita pepo L.were comparatively studied. The experimental results showed that,an experiment was done to verify the accuracy of the model,and it was found that simulation values and measured value were in good agreement,the maximum absolute error of temperature between simulation data with measured result was 1.66℃. Compared with other experimental groups,40℃ hot air treatment 1 h could maximum limit to prolong the occurrence time of chilling injury of postharvest Cucurbita pepo L.,reduced weight loss rate and delay the increase of MDA content and relative conductivity,maintained the fruit of high hardness and ascorbic acid content. Heat transfer model of Cucurbita pepo L. and the relevant conclusions could provide reference for the selection of operation parameters for postharvest heat treatment of Zucchini.