Aggregation, gelation and phase separation of heat denatured globular proteins

beta-lactoglobulin is a globular protein which aggregates after a heat-induced denaturation. It may be considered as a good model system to investigate the processes of aggregation, gelation and phase separation which play a major role in the chemical physics of complex systems. We present here the main results of an extensive study of the denaturation of this protein in various experimental conditions: pH, ionic strength. concentration, temperature, and presence or not of polyoside. The structure and distribution of beta-lactoglobulin aggregates were characterized by dynamic and static light scattering, small angle neutron scattering and size exclusion chromatography. Microscopy was used to study the effect of phase separation on the morphology. The competition between phase separation and aggregation/gelation process is discussed. (C) 2002 Elsevier Science B.V. All rights reserved.