Postharvest Chlorine Dioxide Spray As a Strategy to Maintain Quality in 'monterrey' Strawberry Fruits

Commercial strawberry (Fragaria & times; ananassa) is valued for its quality attributes and its antioxidant content; however, its rapid softening and microbial susceptibility limit their postharvest quality. This study evaluated chlorine dioxide (ClO2) spray at 3 and 5 ppm on the postharvest physiology and biochemical properties of 'Monterrey' strawberries over 9 days. The 3 ppm treatment effectively mitigated weight loss, maintaining fruit mass between 35 and 40 g on days 3-7, whereas control fruit decreased to 25-30 g. Soluble solid content remained stable across treatments (7-10 degrees Brix). Fruit dimensions exhibited a positive response, with increases of 10-15% in width and 8-12% in height under 3 ppm ClO2. Significant biochemical changes were also observed in ClO2 treatments: total phenolics rose to approximately 600 mg GAE/100 g FW at 5 ppm, with concomitant increases in flavonoids, anthocyanins, and antioxidant capacity (FRAP), which improved by 20-30%. Furthermore, ClO2 treatment modulated alpha-mannosidase and beta-acetylhexosaminidase activities in a concentration- and time-dependent manner during postharvest storage. Collectively, these findings demonstrate that ClO2 spray - particularly at 3-5 ppm - enhances fruit retention, preserves antioxidant potential, and downregulates cell wall-degrading enzymes, offering a cost-effective strategy for improving postharvest quality in commercial strawberries.