Journal of Horticulture and Postharvest Research

Abstract Purpose: Papaya is one of the most common fruits which has been produced in southern part of Iran for fresh consumption. Demand for fresh-cut products has increased due to the changes in consumer attitudes. However, fresh-cut papaya is prone to softening during storage. This study carried out to determine effects of calcium lactate and hot water treatments (HWT) for maintaining fresh-cut papaya quality. Research method: After preparing fresh cut cubes of papayas, the pieces were dipped in calcium lactate (CaL) or combined with HWT. Physico-chemical parameters including calcium concentration (Ca), firmness and soluble solids concentration, catalase and peroxidaseactivities, pectin methyl esterase (PME) and polygalacturonase activities (PG),total phenolic content and radical scavenging activities, and microbial growth were measured during 9 days of storage at 5 ^◦C. Findings: At the end of storage, CaL treatment combined with HWT increased calcium (Ca) concentration, catalase activity, total phenolic content and radical scavenging activities (DPPH) of papaya slices, but decreased peroxidase, PG and PME activities compared to the control. In addition, these treatments reduced microbial growth compared to the control. Limitations: No limitations were encountered. Originality/Value: Both HWT with CaL showed potential for increasing markeabitity on fresh cut papaya with their generally recognized as safe status for consumers.

Abstract Purpose: In Bangladesh,mango fruit supply is limited in the local market as well as for export due to its short self-life and susceptibility to post-harvest diseases. This study aimed to evaluate the effects of CaCl₂ in hot water on organoleptic and biochemical characteristics of mango fruits for extension of shelf-life. Research Method: Mangoes were treated with different concentrations (0.0, 0.5, 1, 2, 3, 4 & 5 %) of CaCl₂ in hot water (50°C) for 10 min and kept at 25±2°C over 12 days. Each treatment included 20 mangoes with three replications. The physiological changes were observed and biochemical characteristics of mango fruits were analyzed. Findings: Better skin color and aroma were observed at 0.5~4.0% CaCl₂ and no fungal infection was found at 3~5% CaCl₂ as compared with untreated control whereas taste and texture of mangoes increased significantly with the increasing concentration of CaCl₂. The shelf life of treated mangoes increased 2~3 days with increasing concentration of 4~5% CaCl₂ but slight skin shriveling and weight loss were observed. Higher concentration of CaCl₂ treated fruits maintained higher values of moisture, ash, titratable acidity, vitamin-C, reducing sugar, starch, invertase activity whereas total soluble solid, total sugar, non-reducing sugar, total phenol, amylase, polyphenoloxidase activity decreased significantly. Limitations: In future, mechanism of CaCl₂ in hot water for extending shelf life of mangoes will be elucidated using molecular approach.  Originality/Value: The treatment of 4% CaCl₂ in hot water could be used to extend the shelf life of mangoes up to 2~3 days with consumer acceptance.