Extraction and characterization of ultrasound assisted extraction: improved functional quality of pectin from jackfruit (Artocarpus heterophyllus Lam.) peel waste

Jackfruit peels are potential waste for valorization and extraction of pectin and quality of pectin is a function of extraction conditions. Present study evaluates the effect of low temperature (LT) extraction; mediated through ultrasonication on the quality of pectin from jackfruit peel waste (JP). We first optimized ultrasound assisted extraction (UAE) process through response surface methodology (RSM) based on a Box-Behnken design (BBD) and arrived at optimal extraction conditions with maximum pectin yield and galacturonic acid content (GalA). Pectin extracted at LT and conventional high temperature (HT) referred as UAE-P and CE-P respectively were compared for their technological and structural properties. GalA content ranged between 65.53 and 68.65% in CE-P and UAE-P respectively. UAE-P had methoxyl content (5.58), protein (1.69%), molecular weight (149.67), total phenolic content (1645 mg GAE/100 g), and antioxidant capacity (123.76 µmol TE/g). There were significant (p < 0.05) differences in the Arabinose (Ara) content, FTIR spectra and functionality of pectin extracted at LT and HT. The Ara content was ~ twofold higher while antioxidant activity was ~ 1.66-fold higher in LT extracted UAE-P pectin. Hypoglycemic activity as determined by in vitro α–amylase and α–glucosidase inhibitory activity was significantly higher (p < 0.05) in UAE-P in comparison to CE-P. The DE value of UAE-P (38.11%) was low (< 50%) thus it was categorized as low methoxyl pectin. Results suggests that the UAE is potential efficient green method to obtain high quality food grade pectin with higher yield and functionality in short duration