Observations of the Effects of Hops on Fermentation

J. Harland Anderson and S.T. Likens

Abstract
A metabolic effect is produced on yeast by hops. The modifier, not yet specifically identified, is a component of the whole lupulin glands of hops. To the brewer, the side reactions and excretory products of the alcoholic fermentation by yeast�the higher alcohols, esters, aldehydes, and organic acids�are basic to the taste properties of beer. The involvement of a metabolic modifier from hop extractives then becomes suspect to having an effect on the results of these side reactions in fermentation.

Keywords: hop extracts, GTC stability, fermentometer, yeast