Relation between the denaturation and fouling behaviour of beta-lactoglobulin

The deposition of whey proteins, that is, fouling, was studied with the aim of finding ways to prevent or diminish fouling of heat exchangers. Whey protein solutions were given different heat treatments after which their deposition on a chromium oxide surface was measured by reflectometry. The rate of deposition is related to a model for heat-induced denaturation leading to transient activation and subsequent aggregation of beta-lactoglobulin (beta-lg). The results show that if beta-lg is present in its native form or if it is totally aggregated hardly any deposition takes place. For deposition, denaturation of the whey proteins-in the vicinity of the surface is a prerequisite. It was possible to quantify the rate of deposition by relating it to the concentration of activated molecules.