Peach Fruit Ripening and Quality Changes as Affected by High Carbon Dioxide Treatment before Cold Storage

A chilling-sensitive peach (Prunus persica cv. ‘Mibaekdo’) was pre-treated with 30% CO₂ , stored at 7^oC for 4 weeks, and followed by 3 days of subsequent ripening at room temperature. Significant reductions in both chilling injuries and softening were observed during the cold storage and also the subsequent ripening period. The high CO₂ pre-treatment inhibited the decreases of antioxidant activity and the total phenolics. The beneficial effects of high CO₂ were clearly apparent after 3 days at room temperature after cold storage, and the CO₂ treatment had a strong effect on the high phytochemical content in peaches. Our results indicated that high levels of antioxidant activity, total phenolics, and ascorbic acid in the CO₂ treated peach might be directly responsible for reducing chilling injury in peaches under high CO₂, which efficiently protects cells from free radicals induced by chilling stress.