STABILIZATION MECHANISM FOR BUBBLES FORME D IN FRYING FOODS

We investigated about the cause of foaming and the mechanism of its st abilization during frying held in ordinary home kitchen. An extent of foaming was measured by frying sliced potato and estimating the height of bubble layer by placing a cylinder over it. The sliced potato was found to increase bubbling greatly when treated with wheat flour, an e gg and crumb. Analysis of the easily bubbling oil revealed that the co existence of phospholipid and glycolipid accelerated bubbling. Thus it has been elucidated that the phospholipid extracted from an egg and t he glycolipid from wheat flour are the major cause of bubbling. Fluore scent measurements using fluorescent probe-bearing phospholipids showe d that phospholipids could adsorb at the interface between oil and wat er, and form molecular assemblies. From scanning electrical microscopi c observation of bubble films, a multilayer structure of polar lipid w as found to exist. When bubbles developed over oil surface were cooled to separate water, these polar lipids adsorbed to form a multilayer, lamella-type structure, which was presumed to stabilize the bubble fil m.