Production of buttermilk hydrolyzates and their characterization

This paper describes a process of hydrolysis in combination with membrane filtration for the production of novel buttermilk ingredients. Buttermilk, after extensive concentration by microfiltration (0.1 mum pore size membranes) was treated with trypsin alone or in combination with chymotrypsin. The concentrated buttermilk was then filtered to separate the hydrolyzed peptides from a phospholipid-rich fraction derived from the milk fat globule membrane. The fractions were characterized by SDS-PAGE electrophoresis and size exclusion chromatography. In addition, amino acid analysis and high-pressure liquid chromatography on the lipid phase were also carried out. Results from this work showed the potential for production of various value-added ingredients from buttermilk, the by-product of butter making.