• 1-MCP delayed ripening of red-fleshed kiwifruits during cold storage. • 1-MCP maintained firmness by limiting pectin degradation and lowering PG activity. • Ethylene production and respiration rates were strongly suppressed by 1-MCP. • 1-MCP better preserved market-related and sensory qualities during cold storage. • 1-MCP slowed the loss of secondary metabolites and improved antioxidant activity. This study investigated the effects of 1-methylcyclopropene (1-MCP) treatment on postharvest quality, physiological behavior, and antioxidant characteristics of red-fleshed kiwifruits ( Actinidia chinensis cvs. ‘Hongyang’ and ‘Qihong’) during cold storage. Fruits were treated with 1.0 μL L −1 1-MCP for 24 h at 25 °C and stored at 1 °C for 90 days. A comprehensive evaluation was performed based on firmness, pectin degradation, respiration, ethylene production, color attributes, soluble solids, titratable acidity, sensory quality, secondary metabolites, and antioxidant activity. Application of 1-MCP significantly slowed fruit softening and curtailed ethylene and respiration, thereby preserving cell wall integrity and reducing polygalacturonase activity. Notably, both cultivars exhibited prolonged firmness retention and a pronounced reduction in ethylene production and respiration rates, highlighting consistent cultivar-specific responses to the treatment. Treated fruits also retained higher titratable acidity and exhibited slower increases in soluble solids and SSC/TA ratio, indicating delayed ripening. In addition, 1-MCP effectively inhibited color deterioration by maintaining higher L* and b* values and lower total color difference (ΔE), preserving visual freshness. Sensory evaluation further confirmed that 1-MCP delayed rapid ripening-related changes observed in control fruits and helped maintain desirable attributes, including texture, sweetness, and flavor, during cold storage, with cultivar-dependent differences in the magnitude and timing of responses. The treatment significantly reduced the degradation of total phenolics and flavonoids, resulting in enhanced antioxidant activities with four assays. Between cultivars, Hongyang’ exhibited stronger biochemical and visual stability, whereas ‘Qihong’ showed greater physiological responsiveness through firmer texture and stronger suppression of ethylene and respiration. Overall, 1-MCP effectively maintained the physicochemical, biochemical, and antioxidant qualities of red-fleshed kiwifruits, indicating its strong potential as a practical postharvest strategy for extending storage life and preserving nutritional value.
Tilahun et al. (Wed,) studied this question.