Characterization of browning during CO2 deastringency treatment in astringent persimmon fruit

Abstract Deastringency treatment with CO 2 is an effective and convenient method for improving the marketability of persimmon fruit. However, main cultivars in China turn brown very quickly following exposure to a high-CO atmosphere, causing significant economic loss. mechanisms browning under remain largely unknown. In this study, we evaluated components enzymes related fruit browning. The results revealed that astringency was alleviated by simultaneous reduction soluble tannin content accumulation insoluble tannin. During browning, firmness, total phenolic content, phenylalanine ammonia lyase (PAL) activity decreased significantly, whereas malondialdehyde (MDA), superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO) increased suggesting reactive oxygen species (ROS)-scavenging non-enzymatic antioxidants cannot effectively maintain redox reaction balance protect cell membranes from oxidative damage during treatment. An untargeted metabolomics analysis identified 19 polyhydroxyphenols were downregulated -treated fruit, phenolics may act as substrate We also 11 metabolites associated abiotic stress. Together, these study provide valuable information on mechanism induced will contribute ongoing development industry.