Use of polar aprotic solvents to release membranes from milk lipid globules.

In the search for alternatives to physical methods for release of membranes from milk lipid globules, aqueous solutions of the polar aprotic solvents dimethyl sulfoxide and dimethyl formamide were found to cause release of milk fat globule membrane. Membranes released with polar, aprotic solvents displayed some differences in polypeptide, enzymatic, and lipid composition in comparison with membranes released by churning. However, all polypeptide, enzymatic, and lipid constituents measured in membranes released by churning were also present in membranes released with dimethyl formamide and dimethyl sulfoxide. Antigenic and Concanavalin A binding activity of polypeptides was retained during exposure to dimethyl sulfoxide or dimethyl formamide. The solvent method was effective in releasing membrane from lipid globules of cow, rat, and guinea pig milks. This solvent method was rapid and minimized losses attendant with physical methods for release of milk fat globule membrane.