Effects of Modified Atmosphere Packaging on Quality Maintenance of Pleurotus pulmonarius Under Simulated Logistics Temperature Fluctuations

Fresh Pleurotus pulmonarius is highly perishable during logistics because of its high water content, active respiration, and susceptibility to oxidative damage and membrane deterioration. This study optimized modified atmosphere packaging (MAP) conditions and evaluated their effects on postharvest quality and membrane lipid stability under simulated logistics temperature fluctuations. Single-factor and orthogonal experiments were used to optimize the package gas composition, including O2 and CO2 concentrations, as well as the packaging film. The selected MAP treatment (5% O2 + 20% CO2 with ethylene vinyl alcohol copolymer film) was compared with the control during 3 d of simulated logistics at 25 °C followed by 2 d of cold storage at 4 °C. Compared with the control, MAP maintained higher sensory quality, reduced weight loss and browning, and preserved total phenolic and flavonoid contents. It also inhibited O2.− and malondialdehyde accumulation, enhanced superoxide dismutase, catalase, and ascorbate peroxidase activities, and delayed ascorbic acid and glutathione depletion. Moreover, MAP reduced membrane permeability, suppressed lipase, lipoxygenase, and phospholipase D activities, delayed phospholipid degradation, and maintained higher unsaturated fatty acid levels, U/S, and IUFA. These results indicate that MAP delays postharvest deterioration of P. pulmonarius during the 5-day simulated logistics and cold storage period, partly by maintaining ROS homeostasis and membrane lipid stability.