A novel ethylene-control strategy to extend mango shelf life via air plasma purified storage atmospheres

Ethylene accumulation in enclosed storage environments is a primary trigger for ripening and senescence of climacteric fruits, severely limiting postharvest life and marketability, yet existing removal technologies often suffer from limited sustainability, low selectivity, or incompatibility with food systems. In this study, a novel atmosphere-regulation strategy based on air-plasma purification was developed to enable continuous, non-contact control of trace ethylene during postharvest storage. A compact coaxial dielectric barrier discharge (DBD) reactor was integrated into a closed-loop system, allowing ethylene to be selectively oxidized in the gas phase while completely avoiding direct plasma-fruit interaction. Under storage-relevant operating conditions, the system sustained ultra-low ethylene concentrations with removal efficiencies exceeding 98%. Optical emission diagnostics and kinetic modeling revealed that ethylene conversion proceeded through a stable, radical-mediated oxidation dominated by O and OH species, enabling stepwise oxidation rather than non-selective fragmentation. The depth of oxidation was governed by discharge intensity and residence time, enabling independent regulation of ethylene concentration and selectivity. Application in mango storage demonstrated that plasma-purified atmospheres significantly suppressed ambient ethylene accumulation, attenuated endogenous ethylene production and respiration, delayed color development and softening, reduced weight loss and decay, and ultimately prolonged postharvest life. This work established a scalable, non-contact and food-compatible strategy for continuous ethylene management and provided mechanistic insight into plasma-assisted atmosphere control, offering a new pathway for extending the shelf life of climacteric fruits.