Isoelectric precipitation of soy protein. II. Kinetics of protein aggregate growth and breakage

Protein aggregate growth and breakage in agitated suspensions are modeled. The model includes growth of particles by a turbulent collision mechanism and breakage by a hydrodynamic shear mechanism. In the model, breakage results in the splitting of the particles into several small fragments. The model parameters are a growth rate constant and a breakage rate constant. Aggregate size distributions were measured with a Coulter counter and the data interpreted using a population balance that governs the steady-state particle size distribution in a continuous stirred tank reactor. Effects of changes in the operating variables pH, concentration, mean residence time, ionic strength, and mixing power input on the model kinetic parameters are investigated.