Chitosan, carbon dioxide, and modified atmosphere packaging: Effective postharvest treatments for prolonging the shelf life and quality of ripened 'Irwin' mangoes

Abstract

'Irwin' mangoes are highly perishable, with rapid postharvest deterioration limiting their shelf-life and marketability. Despite the known benefits of individual treatments like chitosan coatings, carbon dioxide (CO2) exposure, and modified atmosphere packaging (MAP), comparative evaluations of these treatments under realistic storage conditions remain limited. This study addresses this gap by investigating the effects of chitosan, CO2, and MAP on the shelf life and quality of fully ripened 'Irwin' mangoes stored under two storage conditions: room temperature (20 degrees C) for 12 days, and cold storage (7 degrees C) for 14 days followed by 9 days at ambient temperature to simulate commercial market conditions. The treatments included 1 % chitosan, 10 % CO2 for 2 h, and 150,000 cc MAP. The physicochemical characteristics, respiratory gases, ethylene content, and disease incidence were then measured. Among the treatments, MAP was the most effective in preserving fruit quality. It significantly reduced weight loss to 0.7 % at room temperature and 0.8 % after cold storage, compared to 11.4 % and 9.5 % in untreated fruits, respectively. Firmness was better retained in MAP-treated mangoes (4.2 N) than in controls. Additionally, MAP-treated fruits showed the lowest incidence of anthracnose lesions (<1 %) and maintained acceptable external appearance throughout storage. Chitosan treatment moderately reduced disease severity but caused surface wrinkling, while CO2 treatment had a limited impact. Overall, MAP was the most effective treatment, extending total shelf-life to 20 days while preserving physicochemical and visual quality. These results demonstrate the practical value of MAP as a scalable postharvest strategy for reducing losses and enhancing the marketability of 'Irwin' mangoes.