Combined Action of Pure Oxygen Pretreatment and Near-freezing Temperature Storage on the Quality of Fresh-cut Nectarines

Abstract

Abstract Fresh-cut fruits were convenient for consumers but vulnerable to quality deterioration, including browning, softening, and volatile aroma loss. In this study, the effects of pure oxygen (PO) pretreatment and near-freezing temperature (NFT) storage on fresh-cut nectarines were investigated, including changes in browning degree, color shift, enzyme activity, cell membrane permeability, antioxidant activity, and aroma components. Specifically, pure oxygen pretreatment increased the activity of the ROS-scavenger enzymes (POD and CAT), which endows fruit with resistance to environmental stresses before fresh cut and storage. Near-freezing temperature storage is extremely effective in inhibiting browning-related enzyme (PPO) activity and total phenolic content (TPC). Higher antioxidant level and anti-browning effects were observed in fresh-cut nectarines treated with PO + NFT, which demonstrated by the DPPH scavenging action, FRAP, enzyme activity ratios (Ratio 1 and Ratio 2). During the storage for 9 d, firmness of the tissue was preserved, MDA content and membrane permeability were suppressed, which delayed the development of fruit softening and the deformation of cell microstructure. In addition, SSC and TA of fresh-cut nectarines were also well preserved by PO + NFT, which maintained the physiological and metabolic qualities. Electronic nose tests revealed that PO + NFT postponed the volatile aroma deterioration of fresh-cut nectarines. In conclusion, PO + NFT is effective in maintaining the storage quality of fresh-cut nectarines.