The effect of endogenous phenol and gallic acid on structure and functionalities of mung bean protein in aerated emulsion system

Abstract

The objective of this study was to develop functional sodium caseinate substitutes in whipped cream using mung bean protein isolates (MPI). MPI, with endogenous phenol removal (dephenol, DP) or gallic acid (GA) addition, was subjected to pH-shifting process (pH12). The influences of the above modifications on the structure (free sulfhydryl content, surface hydrophobicity, and protein subunits) and foaming properties of MPI were elucidated. Results showed that the pH12-DP treatment of MPI even increased the foaming capacity up to 41.7%, compared to 19.9% for the native one, mainly due to more hydrophobic residues of the protein exposure. With the addition of 240 μmol/g protein of GA, the foaming stability of pH12-MPI was 2.4-fold greater than that without GA. Rheology, microscopy and shape retention of aerated emulsions revealed that pH12-DP-GA treatment of MPI resulted in partial coalescence of fat droplets, leading to a more stable three-dimensional structures of the whipped cream and higher elasticity. The cream with MPI treated by pH12-DP-GA exhibited the γmax and γ∞ values that were closer to the commercial one, demonstrating superior deformation resistance and short-term shape retention.