Hop extracts and method of preparation

摘要

Hop extracts useful in the preparation of anactinic or light stable malt beverages are obtained by a method which does not use organic solvents. The extracts are obtained by first treating a crude hop extract containing humulone with an aqueous reducing solution, heating the resulting mixture to form reduced isohumulone, acidifying the reaction mixture to form an aqueous phase and an organic phase, and then adjusting the temperature to facilitate the separation of the two phases. The organic phase which is obtained contains the desired isomerized and reduced humulone and it can be used per se as an anactinic brew kettle flavoring additive for beer or ale. In a preferred embodiment, the organic phase is further treated with an amount of an aqueous KOH solution sufficient to neutralize the reduced isohumulone and to form both an aqueous phase and a solid phase. The aqueous phase which contains reduced isohumulone of about 90+% purity can be used as an anactinic post-kettle additive and the solid phase which contains the remainder of the reduced isohumulone and other hop constituents can be used as an anactinic brew kettle additive.