CHITRA SONKAR AND GENITHA IMMANUEL
Abstract
The goal of the current investigation was to determine how microwave pre-treatment affectedRefractance window drying of orange pestil based on its quality criteria like colour, ascorbic acid, totalphenolic content, antioxidant activity, and rehydration ratio. Orange pulp was treated with microwavepower levels of 300 W, 450 W, and 600 W at 70, 80, and 90 ðC with two pulp thickness of 2 mm and 3 mm.The findings demonstrated that as the power level of microwave for pre-treating orange pulp increased theRefractance window drying colour parameters L* decreased, with the decrement ranging from 6.7% to14.90%, a* increment ranging from 10.0% to 43.8%, and b* value decrement ranging from 17.7 to 23.60%. Thedried and pre-treated samples were dark and crimson. A rising trend was observed in total phenolic contentand antioxidant activity as microwave power level raised but ascorbic acid concentration declined withincreasing microwave power level, declining from 19.71% to 25.91%. The highest reported total Phenolic content was 40.90 mg GAE/g, and the lowest value was 28.20 mg GAE/g. In terms of their ability to scavengediphenyl-2-picryl hydrazyl (DPPH) radicals, produced orange pestilââ¬â¢s antioxidant activities improved. Themaximum and minimum antioxidant activity concentrations were reported to be 87.70 ümol/g and 78.80ümol/g, respectively. At increased microwave power, a reduced rehydration ratio was seen. The lowestrehydration ratio was 3.97, and the highest rehydration ratio was 5.03. Therefore, it can be inferred that a600W microwave set at 70 ðC might be used to treat orange pulp with a thickness of 2mm, protecting somespecific nutrients while also increasing the pulpââ¬â¢s overall total phenolic content and antioxidant activity.