Effect of Cold Plasma on Storage Quality and Wound Healing of Static Pressure Damaged Golden Delicious Apple

In this study, the effect of different intensities of cold plasma (treatment for 10 and 20 min as low and high intensities, respectively) was evaluated on the storage quality and wound healing of Golden Delicious apples damaged by static pressure treatment (at 60 N for 24 h), and unblemished fruits were used as a control. The results showed that cold plasma generated by dielectric barrier discharge (DBD) could produce O₃ and remove C₂H₄, inhibit the respiratory intensity and C₂H₄ release of damaged fruits, delay the decrease in soluble solid content and firmness, and inhibit the increase in the rate of mass loss. Moreover, cold plasma treatment for 10 min had a more pronounced effect while delaying the browning of fruits. The effect of cold plasma treatment for 10 min on the wound healing of damaged apples was also studied. It was found that that low-intensity cold plasma significantly reduced the indentation of the damaged fruits, and resulted in the breakdown and death of surface cells at the wound site and cell wall fragmentation, thereby inhibiting the progression of fruit damage. Low-intensity cold plasma treatment also increased the total phenol content, initially decreased and then increased the activity of polyphenol oxidase (PPO), decreased the activity of peroxidase (POD), and increased the activity of catalase (CAT), thus delaying fruit senescence and consequently exerting a more pronounced wound healing effect. In summary, low-intensity cold plasma treatment can inhibit the quality deterioration of postharvest Golden Delicious apples caused by mechanical injury, thereby improving the marketability of fruits. It can be used as a green and environmentally friendly technology for postharvest storage and preservation of fruits and vegetables.