Abstract
Refractance window drying is a novel technology with high operational efficiency and high product quality retention compared with conventional drying methods. This study assessed the effect of refractance window dryer water temperature and pulp thickness on nutrient content and the antioxidant activity of jackfruit. Response surface methodology (RSM) was used to optimize the drying temperature and fruit pulp thickness. Optimal drying temperature and pulp thickness were found to be 93.4°C and 2.56 mm, respectively. The respective values for the response variables drying time (min), ascorbic acid (mg/100 g), antioxidant activity (mg/100 g AA equiv) and total carotenoid content (μg/g) were 60.47, 17.97, 82.34, and 13.34, respectively. Models for prediction of these values had R (2) values of .964, .980, .994, and .994, respectively, and nonsignificant lack of fit (p < .05). This indicates the suitability of the model in predicting the RWD operating conditions to produce quality dried jackfruit.