Abstract: The effect and mechanism of carboxymethylated konjac glucomannan (CMKGM) with different molecular masses (1.57 × 105–7.88 × 105 Da) and degrees of substitution (0–1.63) on stabilizing pea protein dispersion (PPD) were investigated under neutral and acidic (pH 3.5) conditions. The experimental results showed that the critical CMKGM concentration required to stabilize PPD differed depending on its molecular parameters. The influence of the molecular mass on the stability of PPD was greater than that of the degree of substitution (DS). At neutral condition, the viscosity-enhancing effect of CMKGM on the continuous phase played a major role in the stabilization of PPD, whereas at acidic condition the electrostatic repulsion and steric hindrance induced by the electrostatic CMKGM/protein complexes mainly contributed to the stabilization of PPD in addition to increasing the viscosity of the continuous phase.

Key words: pea protein; aqueous dispersion; carboxymethylated konjac glucomannan; adsorption; colloidal stability