Effects of postharvest treatments on the quality attributes of guava (Psidium guajava L.)

Abstract

Although guava is a dense, nutrient-rich fruit, it has a short shelf life because of its climacteric nature. This study evaluates the effects of postharvest treatments, including hot water treatment (HWT), calcium chloride (CaCl₂), chitosan, and perforated polyethylene bag (PPB), on the physicochemical changes and shelf life of guava. The experiment followed a Completely Randomized Design comprising twelve treatment combinations, including HWT, CaCl₂ (1% and 2%), chitosan (0.1% and 0.3%), PPB, HWT + PPB, CaCl₂ 1% + PPB, CaCl₂ 2% + PPB, chitosan 0.1% + PPB, chitosan 0.3% + PPB, and an untreated control, with three replications. The treatment, chitosan 0.3% + PPB, resulted in the minimum weight loss (11.33%), while CaCl₂ 1% + PPB resulted in the highest total soluble solids (12.35°Brix). Though CaCl₂ 2%+ PPB demonstrated extended shelf life (11.67 days), increased firmness (score 2) of guava, chitosan 0.3% + PPB significantly reduced disease incidence (23.33%) and disease severity (25%), minimal color change (score 1.67), and retained the highest vitamin C (34.63 mg/100g) compared to the control. The chitosan 0.3% + PPB also resulted in better colorimeter values (L*, a*, b*, C*, and h°) than other treatments. Moreover, the shelf life of guavas was extended by 12.83 days with the application of chitosan 0.3% + PPB, whereas the control had the lowest shelf life (5.82 days). Overall, the treatment, chitosan 0.3% + PPB, better preserved the postharvest quality and shelf life of guava. Therefore, 0.3% chitosan + PPB can be considered for postharvest management of guava.