LAUSR

BACKGROUND Tara gum is characterized by its high viscosity and medium solubility, which is due to its high molecular mass. However, for many applications, these characteristics are undesirable and make their use infeasible. The present study aimed to evaluate the effect of high-intensity ultrasound on the depolymerization of aqueous solutions of tara gum. The effect of ultrasonication was investigated by viscometry analysis as well as FTIR and solubility. RESULTS The intrinsic viscosity (η) and the molecular weight (Mw ) of tara gum decreased after ultrasound, achieving a molecular weight reduction of 13.50 x 105  g/mol after 60 min of sonication at 25 °C compared to 22.04 x 105  g/mol before treatment. Degradation kinetics were applied to estimate the rate constant of degradation (k). It was found that the k value of tara gum increased with increasing temperature from 25 °C to 55 °C. Partially hydrolyzed tara gum showed greater solubility at the two studied temperatures (25 and 80 °C). Ultrasonic treatment did not change the chemical structure of the tara gum molecules according to the structural analysis by FTIR, confirming its action only as breaking the structure of the polymer. CONCLUSION Ultrasound is a simple method for effectively reducing the molecular weight and viscosity and increasing the solubility of tara gum, without using chemical reagents. The synthesis of partially hydrolyzed tara gum expands its potential for use in food products, including as a soluble dietary fiber. This article is protected by copyright. All rights reserved.