The invention relates to a brewing plant for continuously or discontinuously obtaining and treating a wort in the beer brewery or beverage industry; wherein the wort derived based on a surface filtration, is obtained continuously or discontinuously. In a second device the wort obtained as such, is set to a first temperature between 0 and 85? C. after completing of the thermal treatment of the wort; and an enzyme-containing substrate is added by means of an apparatus. Therein, the first apparatus for setting the temperature of the wort to a first temperature is arranged downstream to an apparatus for keeping hot or boiling of the wort. The apparatus is arranged downstream to the first apparatus for setting the temperature of the wort to the first temperature. Moreover, a corresponding method and corresponding uses are suggested.

The invention relates to a light-stable hop extract comprising at least 1 g per kg of dry matter of one or more hop derived substances represented by formula (I), wherein R?CH(CH.sub.3).sub.2, CH(CH.sub.3)CH.sub.2CH.sub.3 or CH.sub.2CH(CH.sub.3).sub.2. The invention further relates to the use of the light-stable hop extract in beer and to a method of preparing such a hop extract.

##STR00001##

The invention relates to a light-stable hop extract comprising at least 1 g per kg of dry matter of one or more hop derived substances represented by formula (I), wherein R?CH(CH.sub.3).sub.2, CH(CH.sub.3)CH.sub.2CH.sub.3 or CH.sub.2CH(CH.sub.3).sub.2. The invention further relates to the use of the light-stable hop extract in beer and to a method of preparing such a hop extract.

##STR00001##

The invention relates to a method of preparing a light-stable hop extract, said method comprising: providing a pre-isomerised hop extract comprising at least 10% of iso-alpha acids by weight of dry matter, and illuminating the pre-isomerised hop extract, optionally after dilution of the pre-isomerised hop extract.

The invention relates to a method of preparing a light-stable hop extract, said method comprising: providing a pre-isomerised hop extract comprising at least 10% of iso-alpha acids by weight of dry matter, and illuminating the pre-isomerised hop extract, optionally after dilution of the pre-isomerised hop extract.

The invention relates to a process for the production of iso-alpha-acids starting from alpha-acids in which an alpha-acid containing hop extract is mixed with a carbon-containing chemical compound with one or more functional groups containing a (basic) nitrogen atom with a lone pair (or mixtures thereof), either in solvent-free conditions or in the presence of solvents and preferably under an oxygen-free atmosphere. The resulting mixture is subjected to a temperature of at least 278 K for a time sufficient to effect the intended conversion of the alpha-acid reactant into the iso-alpha-acid product. The present invention further relates to iso-alpha-acid compositions obtained by said improved isomerisation process and to the use of said iso-alpha-acid compositions as bittering formulation and/or as source to obtain reduced or hydrogenated iso-alpha-acid compositions.

The invention relates to a process for the production of iso-alpha-acids starting from alpha-acids in which an alpha-acid containing hop extract is mixed with a carbon-containing chemical compound with one or more functional groups containing a (basic) nitrogen atom with a lone pair (or mixtures thereof), either in solvent-free conditions or in the presence of solvents and preferably under an oxygen-free atmosphere. The resulting mixture is subjected to a temperature of at least 278 K for a time sufficient to effect the intended conversion of the alpha-acid reactant into the iso-alpha-acid product. The present invention further relates to iso-alpha-acid compositions obtained by said improved isomerisation process and to the use of said iso-alpha-acid compositions as bittering formulation and/or as source to obtain reduced or hydrogenated iso-alpha-acid compositions.

A method for preparing a hop acid mixture having an enantiomeric excess of a (+)-tetrahydro--acid is disclosed. In the method, a racemate of a tetrahydro--acid is contacted with an amine to form a precipitate having an enantiomeric excess of the (+)-tetrahydro--acid. A method for preparing a hop acid is also disclosed. In the method, a racemate of a tetrahydro--acid is contacted with an amine to form a precipitate comprising a (+)-tetrahydro--acid, and the (+)-tetrahydro--acid is isomerized to a hop acid selected from the group consisting of (+)-trans-tetrahydro-iso--acids, ()-cis-tetrahydro-iso--acids, and mixtures thereof, and reduced to (+)-trans-hexahydroiso--acids and ()-cis-hexahydroiso--acids. An additive for flavoring a malt beverage is also disclosed. The additive includes a bittering agent selected from the group consisting of (+)-trans-tetrahydro-iso--acids, ()-cis-tetrahydro-iso--acids, (+)-trans-hexahydroiso--acids, ()-cis-hexahydroiso--acids, and mixtures thereof.

A method for preparing a hop acid mixture having an enantiomeric excess of a (+)-tetrahydro--acid is disclosed. In the method, a racemate of a tetrahydro--acid is contacted with an amine to form a precipitate having an enantiomeric excess of the (+)-tetrahydro--acid. A method for preparing a hop acid is also disclosed. In the method, a racemate of a tetrahydro--acid is contacted with an amine to form a precipitate comprising a (+)-tetrahydro--acid, and the (+)-tetrahydro--acid is isomerized to a hop acid selected from the group consisting of (+)-trans-tetrahydro-iso--acids, ()-cis-tetrahydro-iso--acids, and mixtures thereof, and reduced to (+)-trans-hexahydroiso--acids and ()-cis-hexahydroiso--acids. An additive for flavoring a malt beverage is also disclosed. The additive includes a bittering agent selected from the group consisting of (+)-trans-tetrahydro-iso--acids, ()-cis-tetrahydro-iso--acids, (+)-trans-hexahydroiso--acids, ()-cis-hexahydroiso--acids, and mixtures thereof.

The present invention relates to a method for extraction and dissolution of hop acids, including alpha-acids, iso-alpha-acids, beta-acids and derivatives thereof, in aqueous media, comprising the formation of quaternary ammonium salts of hop acids with quaternary ammonium compounds or mixtures thereof; The invention further relates to, the use of quaternary ammonium salts of hop acids in the beer brewing process. The present invention further relates to a method for preparing a brewed beverage, particularly for brewing a beer, and in particular to a method to improve the utilization of hop acids, including alpha-acids and (reduced) iso-alpha-acids in the brewing process.