ABSTRACT
In practice, for any real food colloid, the precise form of Wtot(r)is never properly known. But what can sometimes be inferred is the likely mechanism of stabilization and the approximate magnitude of some limiting energy barrier or attractive well depth. The latter quantities are typically estimated from experimental observations of coagulation kinetics, phase transitions, or rheology. The link is achieved using established theory, which relates a measured quantity (turbidity, viscosity, etc.) to the interparticle interactions. But as the validity of any theory normally relies on assumptions that are of questionable validity when applied to complex food systems, the potential parameters inferred in this way can be regarded as only a rough indication of relative interaction strengths, and not numbers of absolute significance (Dickinson, 1997). On a more positive note, though, it is recognized that transitions between dispersed and flocculated colloidal states are controlled primarily by thermodynamic factors. The following example for a milk protein-based system provides evidence of the success of this thermodynamic approach.
