Synergistic effects of pH-shifting and sonication on lentil protein–xanthan gum complex formation

Abstract

Lentil proteins (LPs) and xanthan gum (XG) are recognized for their diverse techno-functional properties and potential applications in food formulation. This study aimed to develop novel LP-XG complexes by incorporating XG at concentrations ranging from 0.01 to 0.1% into LP dispersions (1%, w/w) using a non-thermal pH-shifting coupled with ultrasonication strategy to enhance the functional properties of LPs. The effects of these treatments on complexation were assessed by evaluating the structural and thermal properties of the resulting LP-XG complexes using fluorescence spectroscopy and UV–visible spectrophotometry. The surface properties of LP-XG complexes were also evaluated. The treatments induced significant (P < 0.05) modifications in the amide I region of LPs and enhanced thermal stability, with the denaturation temperature increasing from 105.1 to 108.6 °C. In addition, the solubility of the LP-XG complexes improved from 52 to 61%, and in vitro protein digestibility rose from 64.2 to 71.6%. These results demonstrate the potential of non-thermal processing techniques to modulate the structural attributes and improve the functional performance of LP-XG complexes, offering promising implications for their application in food product development.