Effect of ultrasound and enzymatic hydrolysis on the physicochemical and functional properties of different galactomannan gums

Abstract

Galactomannans are polysaccharides commonly extracted from the endosperm of various leguminous seeds, exhibiting variations in their man/gal ratio based on their botanical origin. These gums are highly valued for their biodegradability and excellent stability. However, their applications have been limited due to their high viscosity and molecular weight. In this study, we explore the enzymatic and ultrasound depolymerization of galactomannans, resulting in the production of freeze-dried hydrolysates that are subsequently characterized. The hydrolysis process leads to a decrease in viscosity and molecular weight, accompanied by a noticeable increase in polydispersity through enzymatic treatment. Thin-layer chromatography (TLC) analysis indicates the generation of subunits consisting of nine or eight members. Fourier-transform infrared (FTIR) spectroscopy analysis demonstrates no significant changes in functional groups following ultrasound hydrolysis. Furthermore, consistent with the TLC results, the hydrolysates display reactivity towards non-enzymatic browning (NEB), yielding intermediate products with limited browning development.This study expands, diversifies, and enhances the potential applications of these galactomannans in the pharmaceutical, cosmetic, and food industries.