Dual-action mechanisms: Combined cold plasma technology for browning inhibition and spoilage bacteriostasis in fresh-cut stem lettuce during postharvest storage.

To address the challenges of rapid quality deterioration and microbial contamination in minimally processed vegetables, this work investigated the effects of combining plasma-activated water (PAW) with dielectric barrier discharge plasma (DBD) on fresh-cut stem lettuce. The data revealed that chlorophyll content in treated samples reached 1.34 times that of untreated samples, and levels of ascorbic acid, total phenols, and total flavonoids contents increased by 94.7%, 98.5%, and 1.86%, respectively. Furthermore, the treatment enhanced the radical scavenging capacity (41%-68%) and elevated antioxidant enzyme activities (12%-80%). The treatment also effectively suppressed polyphenol oxidase and peroxidase activities by 15%-21%. Additionally, PAW-DBD treatment enhanced intracellular ROS levels, diminished antioxidant defenses, and intensified lipid peroxidation in Pectobacterium sp. These findings suggest that PAW-DBD treatment holds promise for developing novel preservation strategies for minimally processed produce.