Denaturation in a food context, describes what happens to proteins as a first result of being heated (or as a result of acidification, or of violent agitation, or of being cooled below a critical temperature). Their structure is shaken loose, and an ‘unfolding of molecules’ takes place. This unfolding exposes the protein chains to each other to a greater extent, opening the way to cross-bonding between them, which will result eventually in first flocculation and then coagulation.
When denaturation takes place, some of the physical and biological properties (but not the nutritional qualities) of the proteins are affected. These changes are usually, but not invariably, irreversible. In contrast, the further changes which typically occur when proteins are subjected to higher heat and which bring about coagulation, are always irreversible.
