Extraction and Encapsulation of Bioactive Components from Persimmon Peel

Abstract

newline Effect of four different drying techniques viz., hot air drying, microwave pretreated hot air drying, freeze drying and microwave pretreated freeze drying on the quality of persimmon peel was studied. Freeze drying led to significantly higher nutritive value, vitamin C content (70.16 mg/100g), total carotenoid content (3.05 mg/g), total phenolic content (29.21 mg GAE/g), total flavonoid content (17.70 mg GAE/g), colour parameters and antioxidant activity (77.42%) of persimmon peel powder compared with other drying methods. Freeze dried persimmon peel was thus used for extraction of bioactive components using different solvents (distilled water, hexane, ethanol and ethyl lactate) and two extraction methods (microwave assisted extraction and conventional solvent extraction). Persimmon peel extracted by microwave assisted extraction using ethyl lactate as a solvent showed the highest yield (38.23%), total phenolic content (36.80 mg GAE/g), total flavonoid content (23.18 mg QE/g) and antioxidant activity (83.68%) compared to the other extracts obtained by conventional solvent extraction. Ethyl lactate extract obtained by microwave assisted extraction was thus encapsulated using different encapsulating agents (maltodextrin, soy protein isolate, gum arabic, maltodextrin and gum arabic and soy protein isolate and gum arabic). As compared to non-encapsulated extract, encapsulated powders resulted in higher retention of bioactive components after six months of storage due to protective nature of the coating material. Soy protein isolate resulted in higher encapsulation efficiency (90.56%), highest total phenolic content (30.08 mg GAE/g), total flavonoid content (19.61 mg QE/g) and antioxidant activity (79.99%) while maltodextrin resulted in better flowability (21.23% CI and 1.27 HR).