Determination of High Molecular Weight Proteins in Beer Using Coomassie Blue. V. Hii and W. C. Herwig, Miller Brewing Company, Milwaukee, WI 53201. J. Am. Soc. Brew. Chem. 40:0046, 1982.

The Coomassie blue method of Bradford is an excellent means of measuring proteins in beer. Kjeldahl nitrogen, the Lowry method, and the biuret procedure have limited applicability to the measurement of proteins in beer. Current procedures using the Coomassie blue method relate protein concentration to color developed with standards such as bovine serum albumin and ?-globulin. These standards cannot be directly related to beer proteins. Significant correlation was achieved between Coomassie blue dye-binding and the high molecular weight nitrogen fraction of beers isolated by gel filtration. The correlation was linear over a wide variety of beers and chillproofing methods. The Coomassie blue method for high molecular weight nitrogen might be a better criterion for measuring proteins in beer than the Kjeldahl method presently used.

Keywords: Analysis, Beer, Coomassie brilliant blue G-250, Dye-binding, Protein.