The phase changes of the complex monolayer composed of DMPC and β- lactoglobulin or β-casein during the compression process were investigated. The self-assembly process of the phospholipid and the protein at the air/water interface was observed via Brewster angle microscopy. It was found that at the low surface pressure during the compress process the linear or piece shape domain appeared with the DMPC/β-casein or the DMPC/β-lactoglobulin complex monolayer, respectively. At the higher surface pressure, the hook shape domains were formed for the DMPC/β-casein system.

Key words: PROTEIN, PHOSPHOLIPID, MONOMOLECULAR FILMS, PHASE TRANSFORMATION