Optimization of Antioxidant Content in Apple (Malus pumila) Squash Formulations during Storage

Apple is known for its vast health benefits, especially antioxidants content. Apple squash is a product of apple pulp, sugar and water and is used as a drink. The objective of this study was to evaluate the impact of formulation and storage time on the antioxidant contents (total phenol and ascorbic acid), physico-chemical parameters (total soluble solids, pH, acidity and browning), and sensory attributes of apple squash. Fresh apple pieces were cooked in 20% (w/w) water and then pulped. Six formulations containing fruit pulp, water, sugar, citric acid, maleic acid, and gaur gum, i.e., T1 (16.67%, 33.33%, 50%, 4.0 g.l, 0.0, 0.0), T2 (25%, 25%, 50%, 4.0 g.l, 0.0, 0.0), T3 (16.67%, 33.33%, 50%, 4.0 g.l, 0.0, 5.0 g.l), T4 (25%, 25%, 50%, 4 g.l, 0.0, 5 g.l), T5 (16.67%, 33.33%, 50%, 1 g.l, 3 g.l, 5 g.l) and T6 (25%, 25%, 50%, 1.0 g.l, 3.0 g.l: 5 g.l), respectively, were prepared. Ascorbic acid content ranged from 6.06 to 2.58 mg/100 g and was significantly (p<0.001) affected by both formulation and storage. Maximum antioxidant (ascorbic acid and total phenol) content were recorded in treatment T2, during the four month storage. The storage means of total phenol content 550.12, 540.43, 542.85, 539.46 and 534.13 mg.l for 0, 1, 2, 3, and 4 month revealed slight decrease in phenolic content but the changes were statistically not significant. Results of pH, acidity and browning revealed significant (p<0.001) differences among formulations and storage periods. Maximum scores for sensory evaluation were recorded for treatment T6 followed by T2. The study revealed that the samples with more pulp and peel (T6, T2 and T4) showed higher antioxidant content and organoleptic acceptability of apple squash during storage.