ABSTRACT
As we have seen in the previous chapter, most foods are dispersed systems, and many of the structural elements constitute separate phases. This means that there are phase boundaries or interfaces, and the presence of such interfaces has several important consequences. Substances can adsorb onto the interfaces, and if the interfacial area is large, as is often the case, the adsorbed amounts can be considerable. The adsorption can strongly affect colloidal interaction forces between structural elements, i.e., forces acting perpendicular to the interface; this is discussed in Chapter 12. Other forces act in the direction of the interface, and these are treated in the present chapter. Altogether, surface phenomena are of considerable importance during processing and for the physical properties, including stability, of most foods.
