Hydrophobins are secreted fungal proteins in the form of small lipopetide biosurfactants. They are strongly surface active and self assemble at interfaces and in solution. This strong surface activity gives rise to powerful emulsion and foam stability properties, and some unique film forming properties. A potentially important area of application of hydrophobin (hfb2) is in food related foam and emulsion formulations. Such applications will invariably involve other surface active proteins (β-casein, β-lactaglobulin) and hence there is a strong impetus to understanding their co-adsorption with other proteins. This is the focus of this proposal, where we request beam time on INTER to complete the study of the competitive adsorption of hfb2 / β-casein and hfb2 / β-lactoglobulin mixtures at the air-solution interface.