Betacyanin, Antioxidant Activity and Shelf-life Evaluation of Thermally, Microwave, and Chemically Processed Lime-flavored Dragon Fruit Ready to Serve Beverage

Abstract

The exploration regarding the utilization of cacti family fruits into the directly consumable drink is limited. So, study was conducted to explore utilization of local fruit lime for preparation of lime-flavored dragon fruit ready to serve beverage, and processed with thermal, microwave, and chemical treatments to increase the shelf-life of beverage. Standardizing lime juice in dragon fruit ready to serve (RTS) beverages, optimizing thermal, microwave, and chemical treatments, and studying shelf life were the goals of this study. Dragon fruit RTS beverage was made with 12% fruit juice, 12°Brix total soluble solids (TSS), and 0.1% citric acid after a preliminary sensory study. Dragon fruit RTS with 3% lime juice tasted best. The standardized RTS beverage was thermal (70, 80, and 90°C for 5, 10, and 15 min), microwave (900 W power density for 30, 60, 90, 120, and 150 sec), and chemical (500, 1000, and 1500 ppm ascorbic acid incorporation) treated to optimize betacyanin content, antioxidant activity, and sensory evaluation. RTS beverage thermally treated at 70°C for 5 min, a 30-second microwave treatment at 900 W, and RTS beverage with 500 ppm ascorbic acid were found best on betacyanin, antioxidant activity, and sensory basis. The shelf life of optimized RTS beverage was tested at room temperature and refrigerated. During storage at the both temperatures, there were significant variations in pH, TSS, betacyanin content, and sensory qualities. The best retention of betacyanin content was reported on the 6th day of ambient storage for lime-flavored dragon fruit RTS beverage with 500 ppm (10.04 mg/L) with overall acceptability of 5.57. For refrigerator storage, lime-flavored dragon fruit RTS beverage with 500 ppm ascorbic acid retained 24.26 mg/L betacyanin and 5.68 overall acceptability on the 60th day. Additionally, the lime-flavored dragon fruit RTS beverage with 500 ppm ascorbic acid retained betacyanin better than other treatments during ambient and refrigerated storage.