MEETING OF THE HAZE GROUP HELD IN LONDON ON 29th APRIL, 1964: THE POLYPHENOL COMPOSITION OF NON-BIOLOGICAL HAZES OF BEERS

Abstract

Collaborative studies have shown that the polyphenolic fractions of haze preparations from different beers contain major quantities of anthocyanogens. Methylated phenolic acids, derived presumably from lignin, and catechins are also important constituents. Beer haze material is derived from both malt and hops, the contribution from malt being the more important, and the tannins in haze are ultimately derived, by polymerization, largely from comparatively simple polyphenols. Nylon 66 and PVP 700 (polyvinyl pyrrolidone) adsorb or precipitate anthocyanogen-protein associations, thus enhancing potential stability. Future work on beer hazes is likely to involve detailed study of the dynamic oxidation-reduction balance of proteins and tannins in relation to metallic ions and materials such as sulphydryl-containing compounds.