Abstract: Tetrahydroisohumulones are prepared from isohumulones by hydrogenating the isohumulones in a reaction solvent of ethanol containing up to about 15% water in the presence of about 1 to about 40 psig of hydrogen and a hydrogenation catalyst to form tetrahydroisohumulones.

Abstract: The invention is an apparatus and method for preparing volatiles collected from a sample for gas chromatographic analysis. Volatiles are collected from the sample in a volatile trap, such as a porous polymer trap. The volatile trap is then connected to a transfer line. The trap is heated to thermally desorb the volatiles, and an inert gas, such as helium, flows through the heated trap to transport volatiles through the transfer line into a capillary column located in a gas chromatograph oven. Inside of the oven, a portion of the capillary column is cooled with a cooling fluid such as liquid nitrogen to form a cold trap. When the cold trap is cooled, the desorbed volatiles are trapped in the cold trap. Then the cold trap is heated to allow the volatiles to be released and the volatiles are carried to the remainder of the capillary column for chromatographic analysis by an inert carrier gas.

Abstract: A method of removing a valuable protein from a complex solution and recovering the valuable protein in purified form consists of adding a silica gel sorbant having a pore size approximately the molecular size of the protein to a solution containing the protein, allowing the protein to be sorbed onto the sorbant, separating the sorbant from the solution and then recovering the protein from the sorbant.

Abstract: A document generation system which employs a definition-based expert system and an editor to produce an output document from a template document and expert system responses. The knowledge base of the expert system consists of a hierarchy of terms and their definitions. To produce an expert response, an inference engine component of the expert system evaluates a term by evaluating all of the definitions for the terms which are in that term's hierarchy of definitions. In the document generation system, the terms include fragment terms which are defined as portions of the template document.

Abstract: A method of preparing anactinic hop extracts comprising three stages: pre-purification of a liquid CO.sub.2 hop extract using liquid-liquid extraction to isolate pure humulones or alpha acids; isomerization/reduction of the humulones to obtain a mixture consisting of reduced isohumulones and non-isohumulone light unstable products (NILUPS); then adding alkali and water to the mixture of reduced isohumulones and NILUPS, heating and stirring to extract the reduced isohumulones into an aqueous phase and to leave the NILUPS in an oil phase. The aqueous phase is an anactinic hop extract which can be used to prepare light stable malt beverages.

Abstract: A hopping material useful as a kettle additive in preparing anactinic malt beverages is prepared by a method which includes first forming an aqueous suspension of crude hops, containing alpha acids and cellulosic material and alkali hydroxide and an alkali borohydride. The suspension, which has a pH above about 10.5, is heated to isomerize and reduce the alpha acids initially present in the hops. The pH is lowered to about 2 to convert the reduced iso-alpha acids to their free acid forms so that they are adsorbed on cellulosic hop material in the reaction mixture. The cellulosic material which now contains the free isomerized and reduced alpha acids is isolated and is useful as an anactinic kettle additive which can be stored for prolonged periods with no decomposition.

Abstract: Tetrahydroisohumulones are prepared from beta-acids without using objectionable organic solvents by treating the beta-acids to form desoxytetrahydrohumulones which are dissolved in an aqueous alcoholic caustic solution and then oxidized and isomerized with an oxygen-containing gas in the presence of metallic ion to form the desired tetrahydroisohumulones.

Abstract: A traditional flavored fermented alcoholic beverage of low alcohol content is prepared by reverse osmosis with a thin layer composite membrane which has a support layer of polysulfone, a barrier layer of polymer prepared from a polyamine and a polyacyl, and a fiber backing. The membrane has a molecular weight cut-off of less than about 100 for organics and rejects the volatile components which contribute to flavor and aroma and permits about 25 to about 30% alcohol in the beverage to pass.

Abstract: Beta-acids are separated from alpha-acids in a hop extract without using organic solvents by bubbling CO.sub.2 through an aqueous hop extract having a pH of about 9.6 to about 13 to lower the pH to about 8.5 to about 9.5 to precipitate the beta-acids and leave the alpha-acids in the extract.

Abstract: A method of preparing a stable citrus flavored alcoholic malt beverage which does not form off aromas on storage comprises subjecting a feed or beer which contains components which can in the presence of citrus flavoring agents cause off aromas upon storage to reverse osmosis employing a membrane having a molecular weight cutoff of up to about 200 to remove substantial amounts of sulfur containing amino acids and other labile components which in the presence of citrus flavoring can cause off aromas, collecting the permeate which passes through said membrane and using it as the alcoholic base to which the citrus flavoring is added to obtain a stable citrus flavored alcoholic malt beverage.

Abstract: 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.