摘要:
The present study was used to investigate the effect of heat-transfer process on the chilling resistance of coldsensitive 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 Lduring heat treatment were studied,the hot air at 40 °C 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 °C.Compared with other experimental groups,40 °C 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.%为了探讨热处理传热过程对果蔬贮藏生理品质的影响规律,建立西葫芦在热激处理过程中的三维数值模型,进行三维非稳态下的数值模拟,研究热处理时西葫芦组织的传热规律及温度动态响应过程,并以40°C的热空气作为热处理介质,对处理时间分别为0.5、1、2、4h西葫芦的保鲜效果进行了对比实验研究.结果表明,40°C热空气处理1h可最大限度地延长采后西葫芦冷害的发生时间,减少果实失重率,延缓丙二醛(MDA)含量和相对电导率的升高,维持较高的果实硬度和抗坏血酸含量.所建的传热模型与实际情况吻合较好,温度最大绝对误差为1.66°C.西葫芦传热模型及相关结论可为西葫芦采后热处理操作参数的确定提供参考.