The viscosity of a protein solution is increased by the denaturation of the protein. This is true both when there is the formation of protein aggregates which occlude water and when there is no aggregation. Under certain conditions, as a result of the aggregation following denaturation, a solution containing only one per cent of protein may be converted into a clear gel. The conditions for obtaining very viscous solutions containing little denatured protein are always close to the conditions for actual precipitation and under these conditions the viscosity is very sensitive to slight changes in the concentration of salts and hydrogen ions.
THE EFFECT OF DENATURATION ON THE VISCOSITY OF PROTEIN SYSTEMS