The Brewing Research Foundation

Christopher M Grimmett

Derek R Laws

Frederick R Sharpe

Hop extract containing a high proportion of a desired constituent, hop oil, .alpha.-acids or .beta.-acids, is formed by extracting hops with pressurized fluid carbon dioxide, collecting separate fractions of the extract obtained at different times, and selecting the fraction having a high proportion of the desired constituent. Fractions containing (a) at least 70% of the available hop oil at at least 10% concentration, and (b) at least 25% of the available .alpha.-acids at at least 55% concentration, may be obtained in a single process by extracting initially at a lower temperature in the range 0.degree. C. to -57.degree. C. and subsequently at a higher temperature in the range -5.degree. C. to 31.degree. C.

Growing community of inventors

East Grinstead, United Kingdom

Christopher M Grimmett