Effect of heat shock treatment on reactive oxygen species metabolism and storage quality of fresh-cut sweet pepper

Preservation effect of heat shock treatment on fresh- cut sweet pepper was studied. Fresh- cut pepper was dipped in hot water at 45, 50 and 55℃ for 10, 4 and 1min respectively. Reactive oxygen species level, antioxidant enzyme activities and storage quality index during cold storage at 8℃ were investigated. The results indicated that heat shock treatment at 50℃ for 4min and that at 55℃ for 1min, could effectively inhibit superoxide anion ( O- 2) generation rate, reduce hydrogen peroxide ( H 2 O 2) content.Heat shock treatment could be used as an elicitor to enhance superoxide dismutase ( SOD) , catalase ( CAT) and ascrodate peroxidase ( APX) activities, inhibit peroxidase ( POD) activity and restrain malonaldehyde ( MDA) accumulation.Heat shock treatment could effectively inhibit weight loss and maintain chlorophyll and soluble protein content. The effect of 55℃ 1min heat shock treatment was better than that of 50℃ 4min. The conclusion could be drawn that heat shock treatment could maintain quality of cold storage fresh-cut pepper by inducing reactive oxygen species metabolism.