AT514016B1 - Process for the separate isomerization of alpha acids in the beer production - Google Patents

Abstract

The inventive method for the separate isomerization of α-acids in the beer production, wherein hops or a hop product for isomerization of α-acids is added to an aqueous medium and heated, after which it is added to a beer wort, characterized in that the hops or Heated product containing aqueous medium in the presence of calcium hydroxide is heated to a maximum of 130 ° C, at a rate which is in the range of 90-120 seconds per degree Celsius.

Description

description

PROCESS FOR THE SEPARATE ISOMERIZATION OF α-ACIDS IN THE CONNECTION OF BEER PRODUCTION

The invention relates to a method for the separate isomerization of α-acids in the Rah¬men beer production.

Hops greatly influences the taste of the beer. In principle, hops are added and cooked during wort boiling. When the hops are added, the contained α-acids do not dissolve, but an isomerization of the α-acids to water-soluble iso-α-acids is achieved by the cooking process, whereby the bitter taste is produced in the beer.

In so-called "separate" isomerization, the mixture to be isomerized is not added to the wort and cooked with it, but heated separately from it, with isomerization taking place, and only then added to the wort.

From AT 510 617 A1 a method for the separate isomerization of bitter substances in the course of a brewing process is known. To do this, the mixture to be isomerized is not only heated to a certain temperature and kept hot, but undergoes a specific temperature profile while being kept hot at at least one further temperature lower than the first.

An isomerization process is also known from GB 1308671 A1, wherein aqueous hop extract is heated under alkaline conditions (calcium hydroxide).

From DE 10 2007 061 639 A1 a method for producing a hops extract with an increased proportion of iso-alpha-acids is known, wherein the isomerization in a closed container at a temperature in the range of about 25 ° C to about 80 ° C. is taken. EP 0 240 210 A2, in turn, discloses a process for the preparation of isomerized hop preparations in which hops are mixed with a solid or aqueous alkali metal or alkaline earth metal salt. The isomerization is carried out under pressure at a temperature of at least 80 ° C in a closed vessel.

The inventive method for the separate isomerization of α-acids in the beer making process, wherein hops or a hop product for isomerizing the α-acids is added to an aqueous medium and heated, after which it is added to a beer wort, characterized in that the hops or hop product containing aqueous medium is heated in the presence of calcium hydroxide to a maximum of 130 ° C, at a rate which is in the range of 1.5-2.0 pC / min. To complete the isomerization, the heating is then stopped and the mixture is added e.g. 40-60 minutes with the temperature slightly decreasing, e.g. from 125 ° C to 116 °.

The hop product may e.g. a hops extract, hop pellets or raw hops, as well as any mixtures thereof.

The aqueous medium is advantageously treated with lime milk, i. slaked lime, added, and more preferably in an amount between 0.1-0.4 g of calcium oxide per gram of a-acids, wherein advantageously 0.2 g of calcium oxide per gram of α-acids is used.

A preferred embodiment of the method according to the invention is that the aqueous medium to which the hop or the hop product is added has a temperature in the range of 85-95 °.

A further preferred variant of the method according to the invention is characterized in that the aqueous medium to which the hops or the hop product is added is brewing water because of the low content of residual alkalinity.

A further preferred variant of the method according to the invention is that the hops or the hop product is added in an amount to the aqueous medium, so that a maximum of 1 g of α-acids are present in 100-150 ml of aqueous medium. Lower dilutions of α-acids lead to losses in yield.

Advantages of the method according to the invention: 1. Stability Cis / trans ratio increases in comparison to classical hopping, ie. the aging stability is improved.

2. Aroma The Leitaromakomponente linalool increases depending on the venting time compared to the classical Hopfung by up to 25%.

[0018] 3. Time The method allows to shorten the cooking time by the hop isomerization in a separate container.

4. The yield of iso-alpha-acids increased by the method by 40-45%.

5. By this method, hops extract (C02 or ethanol extract) can be processed alone eben¬so with a yield of 40-45% 6. Quality All relevant substances such as the group of tannins, hop oils, Iso-xanthohumols, beta-acids, etc. are not altered by the process and the wort hopped with HOISO is equivalent in quality to a classic hopped seasoning except for the above-mentioned advantages.

[0024] 7. Cold Heaping A hop solution can be obtained by the process according to the invention so that the concentrations of the hops oils in the desired form (depending on the starting hop) of the wort or beer can be added in the "cold" process step. The aim is to achieve different hops with one and the same hops while the variations are much larger than with the classical hops.

A preferred embodiment of the method according to the invention is described below.

A plant for carrying out the method according to the invention is shown in FIG. This plant consists of components which are described as follows: Figure 1 is a cylindroconical pressure vessel with pellet dosing, Figure 2 is the Cip flow, Figure 3 is a vent, Figure 4 is an extract dosing, [0032 6 is a heating surface, FIG. 7 is a pump, FIG. 8 is an inductive flow meter, FIG. 9 is a hop discharge line, FIG. 10 is a brewing water line, [0038] FIG. Fig. 11 is a condensate line, Fig. 12 is a mixing line, Fig. 13 is the manhole for manual hop dosing, Fig. 14 is a safety valve, Fig. 15 is a lime dissolving tank, Fig. 16 is a stirrer, and [ 0044] 17 is a load cell.

Fig. 18 is a pressure transmitter, Fig. 19 is a temperature measurement, and Fig. 20 is a spiral nozzle. Lime milk approach: 1 part of brewing lime (slaked lime) and 1 part of diatomaceous earth in 10 parts of water.

Hops suspension approach: Dissolve 1 g of alpha as hop extract rock, hop pellets or raw hops and any mixtures thereof in 0.15 liter of brewing water.

Maximum Kalkmilchgabe Approach Hop suspension: pellets 0.30 g / g Alpha extract 0.15 g / g Alpha pH in suspension before adding hops in the reactor about 9.5 -10.0 pH in. [0053] Suspension on reaching a temperature of 125 ° C. in the reactor about 6.0-7.0 Step 1: introduction and mixing of the quantity of water suitable for the isomerization in the ratio: 1 gram alpha to 0.15 liter brewing water , Adding a saturated milk of lime to the extent that the solubility product is not exceeded (eg 0.6 g / l suspension at 1000).

Step 2: Mixing and presentation of the desired hop product Step 3: Mixing and heating the hops - water suspension pH < 9 with ge opened vent valve Fig. 1, no. 3, heating at a heating rate of 1.5 to 2.00 / min to 900, power about 200 hl / h, by means of heating zone or external heat exchanger (expelling the unwanted hop flavorings) ,

Step 4: mixing and heating of the hops - water suspension with closed venting valve, Fig. 1 No. 3 to 1250 power approx. 200 hl / h, by means of heating zone or external heat exchanger with a heating rate of 1.5-2.00 / min (retain the desired hop flavorings).

Step 5: Isomerization time without heating and mixing with closed bleeding valve, Fig. 1 No. 3, 60 min. (retaining the desired hops flavorings).

After expiration of this step chain, an isomerization of the α-acids to iso-α-acids of at least 95% is ensured.

Subsequently, the hop water suspension of the boiling wort is pumped in, this can be done as desired in several applications.

By the system of the hop pre-isomerization on site the following improvements are made possible in comparison to the conventional hop feeding: 1. A saving of the hop consumption of approx. 30% - 50% compared to the conventional hop feed with a constant product quality.

2. The system of hop pre-isomerization makes it possible to carry out the hops at any time during wort boiling.

[0064] 3. According to the current state of the brewhouse technology, the wort boiling times can be considerably shortened while the hop yield remains constant, resulting in a poor primary energy saving.

In addition, the system of hop pre-isomerization allows hop batches after wort cooling, as well as after main fermentation and before filtration. It is thus possible to give each beer its own special hop flavor. This is of particular advantage in the production of hops-flavored beers.

Claims (5)

1. A process for the separate isomerization of α-acids in the production of beer, wherein hops or a hop product for isomerization of α-acids is added to an aqueous medium and heated, after which it is added to a beer wort or beer, characterized in that the hops or Aqueous medium containing hop product is heated in the presence of calcium hydroxide to a maximum of 130 ° C, at a rate which is in the range of 1.5-2.0 qC / min. A method according to claim 2, characterized in that the calcium hydroxide is used in an amount of between 0.1-0.4 g per gram of α-acids. 3. The method according to any one of claims 1 to 2, characterized in that the aqueous medium to which the hops or the hop product is added, has a temperature in the range of 85-95 ° C. 4. The method according to any one of claims 1 to 3, characterized in that the aqueous medium is brewing water. 5. The method according to any one of claims 1 to 4, characterized in that the Hopfenbzw. the hop product is added in an amount to the aqueous medium so that at most 1 g of α-acids are present in 100-150 ml of aqueous medium. For this 1 sheet drawings