Protein Concentration, pH and Ionic Strength Affect Apparent Viscosity of Actomyosin

Response surface methodology was used to compare effects of NaCl protein concentration, and pH on apparent viscosity (ζapp) of natural actomyosin from hake, pork and chicken muscle. Models for the three species had R² of 0.921, 0.915 and 0.814 (P<0.01) for chicken, pork and hake, respectively. Protein concentration and pH increased qapp, whereas higher ionic strength decreased it and had less influence. Interactions occurred between protein concentration and pH. Models did not reveal inter-species differences (P<0.05). However, analysis of variance of regression coefficients for each variable showed some differences due to pH.