Effect of salt extraction on composition, structure, and thermal properties of pea protein
Yi Zhang, Laura Román, Jacob J. K. Kirkensgaard, Milena Corredig
Abstract
Salt plays a vital role in modulating protein solubility during plant protein extraction. This study investigated the effect of salt concentrations during extraction on the composition, structure, and thermal properties of pea protein extracts. Low concentrations (0.0-0.2 M) of NaCl resulted in higher ratio of convicilin and vicilin with higher molar mass. Salt concentration did not affect the molar mass of legumin. With 0.4 M NaCl, protein extractability peaked at 78 % and extracted protein had the highest legumin-to-vicilin ratio. With NaCl concentrations greater than 0.4 M, protein composition of extracts remained unchanged, but the extractability decreased. Salt enhanced the heat stability of all pea proteins, as measured by NanoDSC. This study demonstrated that varying NaCl concentrations during protein extraction resulted in pea proteins with different compositions, structures, and thermal properties, offering valuable insights for developing customized protein extraction. The findings can also be extended to other plant proteins.