Improvement of antioxidant capacity and gray mold resistance of strawberries by combined plasma technology

Abstract

To enhance the preservation of fresh strawberries and promote innovation in preservation technology, plasma-activated salicylic acid was combined with in-package dielectric barrier discharge plasma (PASA-DBD). Effects of combined plasma technology on strawberries were elucidated from the perspectives of phenylpropane metabolism, reactive oxygen metabolism, antioxidant capacity, and gray mold control. The results showed that PASA-DBD treatment slowed down the senescence of the strawberries, significantly increased the total phenol, anthocyanin, and total flavonoid content during storage, reduced the malondialdehyde and H₂O₂ content, and significantly enhanced the antioxidant enzyme (superoxide dismutase, catalase, ascorbate peroxidase) activity. Additionally, PASA-DBD treatments could reduce the incidence of gray mold and strengthen the resistance of strawberries, exhibiting by the increase in the chitinase activity and β-1,3-glucanase activity. This study contributes in exploring new preservation techniques of strawberries in postharvest.