Effect of Spontaneous Modified Atmosphere Packaging on the Quality of Fresh Sweet Corn Stored at Room Temperature

This study examined the effect of various packages on the quality and shelf-life of purple sweet corn stored at ambient temperature, providing a theoretical foundation for the e-commerce logistics and shelf-life sales of purple sweet corn. Fresh purple sweet corn was harvested and packaged using three methods: commercial low-density polyethylene bags (CK), MP30 spontaneous modified atmosphere packaging bags (MP30), and MP30+PVA double-layer composite bags (MP30+PVA). All packaged samples were stored at 25±1 ℃ and 80%±5% relative humidity. The changes in internal gas concentration in different bags, and quality of sweet corn were monitored and analyzed during storage. The results showed that both MP30 and MP30+PVA effectively modified the storage microenvironment, establishing a low-O₂ and high-CO₂ atmosphere within the five days of storage. The color difference values (L^*, a^*, and b^*) of husk leaves increased by 8%~10%, with ΔE values reaching 24.29% and 29.17% of the CK group, respectively, delaying the husk yellowing. On the 5th day of storage, the respiration intensity of the MP30 and MP30+PVA groups decreased by 25.59% and 12.13%, respectively, compared to CK; the weight loss rate decreased by 26.65% and 36.54%, respectively. Additionally, the reduction in the total soluble solids content in the two treatment groups was 23.71% and 20.78% lower than that of the CK group, respectively. Meanwhile, vitamin C content increased by 93.58% and 126.68%, and anthocyanin content exhibited a slight upward trend. Most measured indices showed no significant difference between MP30 and MP30+PVA, though MP30 offered greater cost efficiency. In conclusion, MP30 spontaneous modified atmosphere packaging extends the freshness of purple sweet corn to five days at room temperature while effectively preserving its sensory and nutritional quality. These findings provide a practical solution for room-temperature e-commerce logistics and shelf-life management of fresh sweet corn.