EFFECT OF SPRAY DRYING OF FOUR FRUIT JUICES ON PHYSICOCHEMICAL, PHYTOCHEMICAL AND ANTIOXIDANT PROPERTIES

Fruit juices from Khasi mandarin orange, watermelon, carambola and pineapple were spray dried with 20% maltodextrin and studied for physicochemical, phytochemical and antioxidant properties. Khasi mandarin orange gave the highest yield (85.27%). Viscosity of the feed sample and the particle size distribution of the powders varied among samples. Moisture content ranged between 3.41 and 5.47%. pH was in the acidic range and titratable acidity was highest in carambola (0.70%). Solubility values ranged from 57.57 to 76.75%. Hygroscopicity of the juice powders ranged from 11.63 to 11.99 g/100 g of samples. The change in color (Delta E) after spray drying was highest in reconstituted Khasi mandarin. The phytochemical content and antioxidant activity were significantly different between the spray- dried and fresh untreated juice samples. An increase in total phenolic content, total flavonoid content, ferric reducing antioxidant potential and DPPH radical scavenging activity was observed in Khasi mandarin juice powder.