VIEW ARTICLE DOI: 10.1094/ASBCJ-38-0154
Beer Hazes. I. Isolation and Preliminary Analysis of Phenolic and Carbohydrate Components. M. Dadic and G. Belleau, Molson Breweries of Canada Limited, Montreal, Quebec, Canada H2L 2R5. J. Am. Soc. Brew. Chem. 38:0154, 1980.
Haze was collected from fresh beer by centrifugation (Haze 1), and the water-soluble portion (over 90% of the total weight) was isolated (Haze 2). Water-soluble portions of hazes from an aged beer (Haze 3) and from a beer forced at 60° C for 72 hr (Haze 4) were also isolated. Phenolic concentrates of Hazes 1-4 (Preparations 5-8) were prepared by acid-alkali treatment followed by ether extraction. Phenolic compounds were then separated by high performance liquid chromatography on a Microbondapack C18 column. Eleven phenolic acids, two flavonols (quercetin and kaempferol), d-catechin, and l-epicatechin, were identified and quantified in the hazes. Carbohydrates were separated on an Aminex HPX-87 column, and glucose, maltose, fructose, and a dextrin determined after Sep-pack treatment.
Keywords: Aminex HPX-87, Catechins, Flavonols, HPLC, Microbondapak C18, Phenolic acids