Rheological and thermal characterization of Pinto Saltillo bean (Phaseolus vulgaris L.) protein isolates/sodium alginate gels

Abstract The aim of the present study was to investigate the gelling properties of Pinto Saltillo bean isolate protein (PSBIP) enriched with sodium alginate (SA). In solution, phase diagrams indicated cosolubility at different concentrations of the PSBIP-SA system that is homogeneous at low concentrations of PSBPI ( η 0 obtained using the Carreau model suggest stronger interactions between PSBPI (100 g/L) and SA (20 g/L) indicating the presence of a molecular network that cannot be significantly altered at low shear rates. In frequency studies, mixed gels formed through internal ionic gelation and temperature gradient denaturation, indicates that SA concentrations higher than 20 g/L increase the G’ and G’’ values, improving the mechanical spectra in some cases of the binary gels; the K’, K’’, n’, and n’’ values suggest that the modifications of the dynamic rheological properties of PSBPI-SA gels are synergistic. Viscoelastic analyses indicate that SA reduces the random associations of proteins in the mixed gels due to a more ordered network structure.