Postharvest treatments of hexanal and sodium benzoate to maintain quality and extend shelf life of winter season guava under low-temperature storage

Abstract

In the present investigation, comparative efficacy and potential of postharvest treatment of hexanal and sodium benzoate were evaluated for extending shelf life and maintaining edibility of guava cv. Allahabad Safeda. The fruits were subjected to 5 min dip in aqueous solutions of hexanal (0.005%, 0.01% and 0.015% v/v) or sodium benzoate (0.2mM, 0.4mM, 0.6mM) whereas, the control fruits were dipped in water. Corrugated fibreboard (CFB) boxes with paper lining were used for packing the treated fruits and were kept under cold storage conditions (6 - 8°C, 90–95% RH). Assessment of physicochemical and fruit quality parameters was done at 0 days (before treatment) and weekly interval in storage till 35 days. In general, a gradual decline was noted with time in fruit firmness, pectic substances, phenols, acidity and vitamin C content whereas, physiological loss in weight increased in the stored fruits. Hexanal at a dose of 0.01% v/v effectively minimized decay incidence, retained firmness, phenol content and reduced the pectin degradation by suppressing the pectin methylesterase (PME) activity. Similarly, the treated fruits retained higher TSS and TA during the storage as compared to other treatments. Sodium benzoate treatments also maintained the quality attributes better than the untreated fruit. It was concluded that postharvest dip treatment of Hexanal (0.01% v/v; 0.8 mM) extended the storage life of guava cv. Allahabad safeda from 14 to 21 days as compared to control.