Thin Film Morphology and Tribology Study of Mayonnaise

The texture of food is considered related to its rheological behavior when confined within thin films between two shearing or squeezing surfaces. Such thin-film tribological properties may represent foods undergoing massive grinding and deformation during mastication. The thin-film tribological properties rather than the bulk rheological properties correlated with the composition (oil droplets, etc.) and texture of mayonnaise samples. Using the Surface Forces Apparatus (SFA) technique and optical interferometry using fringes of equal chromatic order, we characterized the thin-film morphology and measured tribological and other interfacial properties of mayonnaise emulsions. Results revealed new properties that help differentiate between full fat, light and fat free mayonnaises. This provides an important approach to determine properties of such foods in thin films which cannot be deduced from bulk properties.