Rheology and Microstructure of Succinylated Canola Protein Isolate

Steady shear rheological properties of aqueous dispersions of unmodified and succinylated canola (rapeseed) protein (54 and 84% modification of free amino groups) were examined over a wide range of pH (3.5–11.0) and NaCl concentration (0.0–0.70M). All dispersions were pseudoplastic and followed power-law or power-law plastic flow behavior. Apparent viscosity at shear rates of 10 and 1000 s-1 was affected by extent of succinylation, pH, NaCl concentration, and interactions among these factors. At both shear rates, protein solubility and hydrophobicity were reliable predictors of apparent viscosity. Dispersion microstructure, as revealed by light microscopy, appeared to play an important role in flow behavior.