The Effects of Gum Arabic and Warm Water Application on Physicochemical and Qualitative Parameters of Table Grape Fruits During the Postharvest Period

Table grape is a non-climacteric fruit; however, it has a short shelf-life. Thus, some treatments that can prolong shelf-life and maintain the quality of table grape fruits are required. This study was carried out as a factorial based on a completely randomized design with two factors: the first factor was the storage period and the second factor was the combination of warm water treatments and gum arabic (GA). Fruits were stored at ۵ °C and ۸۰ % relative humidity in permanent darkness. On days ۰, ۲۰, ۴۰, and ۶۰, seven berries from each replicate were randomly sampled and analyzed for physicochemical and qualitative parameters. Although storage time had a negative effect on the measured traits of ‘Bidaneh Ghermez’ table grape fruits, this effect was lessened by the application of warm water treatments and GA coating, especially ۴۵ °C+GA ۵%. Compared to the uncoated controls, fruits that received ۴۵ °C+GA ۵%, showed more levels of vitamin C (۳۰.۴۳–۱۶۰.۰۰%), TSS/TA (total soluble solids/titratable acidity) (۱۹.۷۶–۲۱.۵۷%), anthocyanin (۳۷.۴۰–۵۷.۷۵%), antioxidant activity (۷.۳۵–۳۶.۴۰%), total phenol (۱۲.۰۱–۲۴.۴۹%), and sensory attributes (۶۶.۶۶–۲۴۸.۵۰%), but lower levels of weight loss (۵۳.۲۷–۴۵.۴۸%), H۲O۲ (hydrogen peroxide) (۹.۹۰–۲۶.۵۵%), and MDA (malondialdehyde) (۸.۸۴–۲۷.۹۲%) during storage. Therefore, the application of warm water treatments and GA coating, particularly ۴۵ °C+GA ۵%, in the shelf-life extension of fruits has revealed remarkable promising potential. The advantages of warm water and GA include their low cost.

Keywords:

Antioxidant activity , Edible coating , H۲O۲ , MDA , total phenol