Effects of Cold Storage Insulation Packaging Box on the Quality of Sweet Corn in Simulated Cold Chain Transportation

Sweet corn was highly susceptible to senescence due to its elevated physiological metabolism after harvest, resulting in a decline in its edible quality. The aim of this study was to assess the effects of a cold storage insulation packaging box on the quality attributes of postharvest sweet corn (cv. 'Jinguan 218') during a simulated cold chain transportation period of 3 d and subsequent shelf life at room temperature (20 ℃) for 1 d. The control group involved cold storage at 4 ℃ to mimic refrigerated truck transportation. The results showed that the internal temperature of sweet corn packed in the cold storage insulation packaging box remained below 7 ℃ throughout the 3 d period. In comparison to the control group, the cold storage insulation packaging box effectively maintained the quality of sweet corn during cold chain transportation and shelf life, and delayed husk discoloration. The mass loss rate of sweet corn was reduced by 72.66% after 3 d of cold chain distribution using the packaging box, the soluble solid content was increased by 4.97%, and soluble sugar content was enhanced by 10.13%. Meanwhile, the activities of peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) in sweet corn packaged with the cold storage insulation packaging box were significantly (P<0.05) higher than those in the control group, although the activity of superoxide dismutase (SOD) was inhibited by cold storage insulation packaging box. Therefore, the cold storage insulation packaging box demonstrated its ability to maintain the quality of sweet corn throughout cold chain logistics and shelf life. This work provides a technical basis for the preservation of sweet corn through cold storage packaging during post-harvest logistics and transportation.