Water holding of soy protein gels is set by coarseness, modulated by calcium binding, rather than gel stiffness

This work aims to differentiate between the contributions to water holding (WH) by gel microstructure and network stiffness of soy protein (SP) gels. SP were succinylated to increase calcium binding affinity, and the presence of different calcium salts were used to generate gels with different morphologies while keeping ionic strength and protein concentration constant. It was found that not gel stiffness, but coarseness (gel microstructure inhomogeneity) is more dominant in setting the WH ability. A higher energy dissipation of applied stress onto the protein network was related to inability of a gel network to retain water. (C) 2014 Elsevier Ltd. All rights reserved.