FRACTIONATION OF SMALL PEPTIDES FROM BEER

Small peptides (MW<1000) were isolated from beer by hollow fibre ultrafiltration followed by column chromatography using the gel matrix Sephadex LH20. This simple procedure enabled the isolation of small peptides relatively free of other low molecular weight nitrogenous compounds. Analysis of the composition of subfractions from the small peptide fraction from pilot brewery beer and a commercial beer using reverse phase HPLC showed superior resolution of individual components compared to previously reported analytical techniques and demonstrated the presence of many peptide components. Acid hydrolysis and amino acid analysis of small peptide subfractions showed that the principal amino acid in each subfraction was glutamic acid/glutamine consistent with the release of peptides by proteolytic degradation of barley and malt proteins.