Quantitative analysis of complex casein hydrolysates based on chromatography and membrane

Abstract

The enzymatic hydrolysates of casein are so complex that there is no effective method to do quantitative analysis. The common techniques, such as high performance chromatography and SDS-PAGE, can only carry out qualitative analysis. On the basis of membrane separation and high performance size exclusion chromatography (HPSEC), standard peptides with different molecular mass range were prepared, and the linear relationships between mass concentration of the standard peptides and the ultraviolet absorption of corresponding peak areas were established. Consequently, mass concentration of the different hydrolysates at different reaction times could be accurately calculated. The combination of chromatography and membrane separation is of great importance to the quantitative analysis of the complex hydrolysates, which can also be applied to the other macromolecular systems, such as carbohydrates.