Quantitative Determination of the Major Components of Casein Mixtures by Column Chromatography on DEAE-Cellulose

Abstract Quantitative determination of the α s -, β -, and κ -casein content of casein samples has been achieved by column chromatography of alkylated samples on DEAE-cellulose in the presence of urea. Resolution of the caseins is not complete, but is reproducible within 2 or 3%, and the estimated accuracy of the method is ±5%. In contrast to methods based on determinations of sialic acid content and of turbidity, the chromatographic method is applicable to casein mixtures of widely varying composition, and is not affected by varying amounts of carbohydrate per molecule of κ -casein or by the presence of minor components such as γ -casein and temperature-sensitive caseins