Physicochemical and functional characterisation of pectin from margarita sweet potato leaves

Underutilised agricultural biomass is a rich source of food ingredients. In this study, pectin from Ipomoea batatas (Margarita) leaves (SPL, or sweet potato leaves) was extracted and evaluated for its physicochemical and functional properties. SPL pectin was composed of galacturonic acid (55.21 ± 2.57%), with a high methylation level of 61.60% and an acetylation level of 3.27%. In comparison to commercially available oat beta-glucan (Promoat® β-glucan), SPL pectin achieved better water holding capacity and emulsion stability index. In vitro starch digestibility test also revealed a dose-response inhibitory effect with increased SPL pectin in both wheat and rice noodles, respectively. Based on these findings, SPL leaves could potentially be upcycled into new functional food ingredients, thereby achieving an effective valorisation process.