Physiochemical properties of encapsulated bitter melon juice using spray drying

Abstract

Bitter melons have been proven with anti-inflammatory and anti-diabetic activities. However, due to its short shelf life and bitter taste, the consumption of bitter melon is limited in the United States.Among many encapsulation technologies, spray drying is a cost-effective method for encapsulation of bioactive compounds. Polysaccharides and proteins are vastly used as wall materials for encapsulation of bioactive compounds. The encapsulation of bitter melon juice can provide protection over the bioactive compounds in juice, and can mask the unpleasant taste. In the current study, fresh bitter melon juice was obtained from the common variety, Indian bitter melon. The juice was encapsulated using spray drying with 3 formulas of various material composition and core to wall ratios, namely formula 1 (maltodextrin + gum Arabic), formula 2 (gum Arabic + pectin), and formula 3 (pectin + soy protein isolate). The particle size and encapsulation efficiency were compared among the three formulas. The physiochemical properties of fresh juice and reconstituted juice form the encapsulated powders were compared in terms of antioxidant activities, anti-diabetic activity and anti-inflammatory properties. The results indicated that all the reconstituted juices showed lower antioxidant activities, anti-diabetic activity and anti-inflammatory properties compared to the fresh juice. Among the three encapsulated particles, the particles of formula 3 exhibited the highest antioxidant activity and anti-inflammatory property. The particles from formula 2 exhibited the best anti-diabetic activity. The findings will help to develop encapsulation formulas using natural polymers with desired stability, bioaccessibility and health benefits of encapsulated bioactive compounds. Also, the results will provide guidelines for encapsulation of fruit and vegetable juices with health benefits for industrial practices.