The lubrication, rheological, and molecular properties of two different protein aggregate dispersions were compared: globular aggregates of whey protein isolate (WPI) and fibrillar aggregates of ovalbumin from egg white. These dispersions are models for the lubricating fluid that is present between the tongue and the palate when consuming liquid or gelled products. To simulate oral conditions, a commercial tribometer was modified so that soft rubber surfaces could be used.
View Article and Find Full Text PDFThe interactions between the two most important colloids in milk, fat globules and casein micelles, were investigated. Mixtures of oil droplets (as a model for fat globules) and casein micelles were prepared, and their phase behavior was studied. It was found that the oil droplets and the casein micelles phase separate as a result of depletion interaction.
View Article and Find Full Text PDFThe proposed biological function of beta-lactoglobulins as transporting proteins assumes a binding ability for ligands and high stability under the acidic conditions of the stomach. This work shows that the conformational stability of nonruminant porcine beta-lactoglobulin (BLG) is not consistent with this hypothesis. Thermal denaturation of porcine BLG was studied by high-sensitivity differential scanning calorimetry within the pH range 2.
View Article and Find Full Text PDF