Functionalization of ash gourd: Infusion of citrus peel polyphenols through vacuum impregnation

Abstract

Citrus peels have high flavonoids known for potent pharmaceutical and food applications. The present study explores the infusion of citrus peel polyphenols (CPP) into ash gourd (Benincasa hispida) through vacuum impregnation (VI). The intent was to functionalize ash gourd for diversifying its food use. Vacuum infused ash gourd (VIAG) cubes were evaluated for physicochemical parameters, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (AOX), and sensory quality. The VI process was optimized through Box-Behnken Design (BBD) of response surface methodology (RSM), considering blanching time, vacuum pressure and vacuum time as independent variables, and TPC, TFC and AOX as dependent variables. At optimized conditions of blanching pre-treatment (2.21 min), vacuum pressure (432.31 mbar) and time (28.18 min), there was ∼300% increase in TPC and AOX. Peleg model validated the mass transfer kinetics for TPC. Sensory evaluation through descriptive analysis revealed no perceived bitterness in VIAG. Overall, it seems that VI is a promising tool for functionalization of ash gourd with bioactives.