Aloe vera Gel Coating Extends Marketability and Maintains Quality by Reducing Rachis Browning and Preserving Bioactive Compounds of Commercial Table Grape Cultivars

The highly perishable nature of table grape (Vitis vinifera L.) berries contributes to the sharp decline in their postharvest shelf and storage life with reduced berry quality and marketability. Thus, the present research was aimed at extending postharvest market potential and maintaining quality of table grapes by using Aloe vera (ALV) gel coating during cold storage. In this study, three commercial table grape cvs. viz. 'Sundarkhani', 'Khismishi' and 'Shaghali' were treated with ALV gel coating (50%) and kept at cold storage (2 +/- 1 degrees C with 90% RH) for 20 days. ALV gel-treated 'Sundarkhani' berries exhibited less rachis browning (2%), berry weight loss (10%), electrolyte leakage (40.1%) and a higher level of total phenolic content (185.98 mg mL-1 FW) than 'Khismishi' and 'Shaghali' berries, respectively. A lower respiration rate (0.29 mmol CO2 kg(-1) h(-1)) and higher level of superoxide dismutase enzyme activity (488.20 U mg(-1) protein) were recorded in ALV gel-treated 'Khismishi' berries than control. Comparably, ALV gel-treated 'Shaghali' berries significantly retained higher berry firmness (0.45 N), marketability index (90%), vitamin C (60.20 mg mL(-1)), total antioxidants (320.40 %DPPH activity) and catalase (104.20 U mg(-1) protein) enzyme activities after 20 days of storage. In conclusion, ALV gel coating (50%) significantly extended the marketability of table grape cvs. 'Sundarkhani' and 'Shaghali' by reducing rachis browning and preserving bioactive compounds during 20 days of storage. Hence, in the grape sector, ALV gel coating could be a practical substitute for synthetic chemicals due to its potential to enhance marketability and maintain freshness and quality.