Effect of hot air treatment on postharvest low temperature stroage characteristic of Cucurbita pepo

The effects of hot air treatment on postharvest low temperature stroage quality of Cucurbita pepo L were studied.The Cucurbita pepo L was treated with hot air at 35 ℃ for 40 min and hot air at 45 ℃ for 20 min, fruits without hot air treatment at room temperature ( 20 ± 2) ℃ as the control, and then stored at 4 ℃ low temperature, the quality and physiological and biochemical indicators were measured every 3 days to evaluate the storage and preservation effect. The results showed that hot air treatment could maintain the firmness, the content of TSS, soluble sugar and soluble protein, reduce the respiration rate compared to the control, and reduce the content of O₂^- and H₂O₂, increase the activities of catalase activity ( CAT) , superoxide dismutase ( SOD) and peroxidase ( POD) , enhance the removal ability of free radicals, reduce the malondialdehyde ( MDA) content and electrolyte leakage rate, slower the membrane lipid peroxidation process, protect the cell membrane, and then reduce the chilling index, indicating that hot air treatment could enhance the resistment capacity of Cucurbita pepo L to low temperature, and in this experiment, 45 ℃, 20 min was the better hot air treatment.