Physiological and quality changes in fresh-cut mango fruit as influenced by cold plasma

Abstract

In this study, fresh-cut (FC) mango cubes were treated with cold plasma (CP) at 75 kV for 3 min using a dielectric barrier discharge (DBD) generator and then stored at 15 °C for 4 d to simulate a shelf life, during which the quality parameters and related physiological metabolisms were evaluated. The results showed that CP treatment effectively delayed the declines in organoleptic and nutritional qualities in FC mangoes, as manifested by higher retentions of chromaticity parameters (L*, a* and b*), firmness, soluble solids content (SSC), titratable acidity (TA), SSC/TA ratio and carotenoids content in CP-treated samples during storage. CP treatment repressed the generation of reactive oxygen species (ROS) (O2-. and H2O2) and reduced the accumulation of malondialdehyde (MDA), thus reducing oxidative damage to FC mangoes. Inhibition of browning-related phenolic oxidation, as demonstrated by higher contents of total phenolics and flavonoids accompanied by lower activities of polyphenol oxidase (PPO) and peroxidase (POD), was noted in CP-treated FC mangoes compared to control FC fruit. CP treatment also maintained antioxidant capacity in stored FC mangoes by increasing the contents of ascorbic acid (AsA) and reduced glutathione (GSH) and enhancing the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR). In addition, CP treatment markedly inhibited the growth of total microbial counts, thus contributing to the improvement of edible safety in FC mangoes. The results suggest that CP treatment could be a promising preservation technology for improving the quality and extending the shelf life of FC mango fruit.