Ultrasound-Assisted Extraction of Pectin From Jackfruit (Artocarpus Heterophyllus) Rags: Optimization, Characterization, and Application in Model Food Gel

Abstract

Jackfruit rags (JR) are an abundant source of pectin, which offers promising health benefits. They can be valorized into a functional ingredient to reduce food waste and supply the local market demand. This research aimed to optimize and characterize the pectin extracted from JR using an ultrasound-assisted method with hydrochloric acid. A central composite design (CCD) was employed to optimize the solid-to-solvent ratio (1:25 to 1:35) and extraction time (15 to 45 mins) to obtain high yield of pectin. The optimal conditions for JR pectin extraction were found to be a solid-to-solvent ratio of 1:34.97 g/mL and an extraction time of 34.69 min, resulting in a pectin yield of 12.53%. The yielded pectin exhibited ash content of 3.64%, galacturonic acid content of 35.79 µg/mL, equivalent weight of 1950.88, methoxyl content of 1.39, anhydrouronic acid content of 31.12%, and degree of ¬esterification of 70.08%. FTIR analysis showed similar chemical group stretching and vibrations in both commercial pectin and JR pectin. The extracted pectin was then applied into model food gel and compared with commercial pectin. JR pectin formed a firm gel structure at low pH as compared to control pectin,¬ however both are classified as high methoxy pectin. Under optimum conditions, the experimental value was in close proximity to the predicted values with no significant difference, thereby validating the regression model. The potential of JR pectin to emerge as a fresh and sustainable source within the food industry is significant, given its comparable quality to commercially available pectin.