Interfacial reactive species in plasma nanobubble water enable rapid wash-water disinfection

Postharvest wash water plays a central role in fresh-produce safety, but it can also become a pathway for pathogen dissemination and cross-contamination. Here, we introduce plasma-treated nanobubble water (PNBW), a residue-free washing medium that combines plasma-generated reactive species with nanobubble interfacial phenomena for rapid microbial control. Plasma-gas injection produced nanobubbles with distinct physicochemical properties, enabling efficient retention and delivery of reactive species. PNBW achieved rapid inactivation of Salmonella Typhimurium in water to below the detection limit (<1.4 log CFU mL −1 ) within 10 s and effectively prevented cross-contamination during tomato washing. Simultaneously, PNBW reduced surface-associated bacteria by 2.32 ± 0.2 log CFU g − 1 within 1 min without measurable deterioration of quality. Scavenger studies identified ozone as the primary antimicrobial agent, while hydroxyl radicals generated through ozone decomposition provided additional contributions. These findings demonstrate that PNBW can improve wash-water hygiene and fresh-produce microbial safety without externally added chemical disinfectants, offering a sustainable strategy for safer water use in postharvest processing.