DE2127618C2 - Process for obtaining hop extracts - Google Patents

Description

closed; the heatable pressure pipe A, the entrances and exits of which are provided with very fine-pored metal filter plates (filter threshold 5 μ), is filled with naturally moist hops. The entire system is first flushed of air _{with dry CO 2 gas.} A liquid gas pump then initially pushes liquid CO ₄ through. the heat exchanger Wl, in which the medium is brought to supercritical conditions of pressure and temperature. It flows through the hops in tube A, where it becomes loaded with resin and essential oils in the sense of a "supercritical solution". In the container B into the loaded medium is expanded by means of a throttle valve through the heat exchanger W3 , whereby the pressure must be lower than ptrtt., Co ₂ , while the temperature can be either higher or lower than ti-, «., Cos- Here a system mix takes place, ie the dissolved hop constituents fall jus and collect in container B. t _B <hrtt .. vo ₂ leads to the liquefaction of the CO ₂ , whereby the water carried along from the pot is also mixed in, with tu > ticrii .. C02 only the resins and essential oils separate and only very little water, so that in this case a resin extract with little water is obtained. This procedure is preferred. If the CO _{8 is} liquefied in the container B, then because of the solubility of the extracts in the liquid CO _{2, gaseous CO 2 must be} sucked in from the vapor phase above the liquid. The extract-free gas liquefies in the heat exchanger Wl, is conveyed by the pump and re-enters the pipe A as a pure dissolving medium, etc. The operating time is about 2 to 10 hours, depending on the system size, process parameters and the desired degree of extraction.

A compressor can also be used instead of the liquid gas pump. In this case, the function of the heat exchanger changes because the gas flow z. B. before entering the compressor in the heat exchanger Wl to a t > tjent. must be brought. In practice, the heat exchangers are interconnected so that operation that is particularly economical in terms of energy requirements is possible.

At the end of the extraction, the CO ₂ is transferred back to the tanks, except for the amount in container B. The valves 5 and 6 are open, all others are closed. Man ensures previously for the fact that in the container B, a certain amount of liquid remains COj which is then also pumped out of the vapor phase, wherein the temperature of the contents of B to max - allowed to fall 10 ⁰ C.. The extract is then so solid that it can be removed from the container with mechanical scrapers without loss. It still contains a certain amount of CO ₂ , which gradually evaporates during the subsequent heating and storage at around 0 ° C and at the same time serves as an inert gas atmosphere for the air-sensitive material.

The total resin of the hops can be extracted quantitatively, and the analysis of the CO _t extract shows that it contains almost only the resin components in addition to water. A special feature of the process is that the -acids important for the bitter can be removed quantitatively from the hops, the / I fraction and the hard resins either completely or only to a certain extent, whereby here again differentiations between the latter can be made both components are possible. This makes it possible in Hami to produce extracts with a particularly high »acid content. . , ..,

Thus, according to a preferred embodiment of the invention, all of the soft resin material and the essential oils of the hops can be used, but less than 1% of the hard resin content. extract by operating at extraction pressures of 100 to 220 atu. According to another preferred embodiment of the invention, the entire ^ acids and the i "essential oils are, however, extracted less than 100% of the ^ acids contained in hops, and less than 100 I ₀ of the hard resin components by at" ιγβκ-tion pressing 100 to 220 atmospheres gauge operates and further separating the extract obtained thereby. that J ₅ it is subjected to a further atm supercritical extraction at pressures of 100 to 150.

The product obtained according to the invention is a light to dark green paste, the color of which depends on the extraction temperature; it is "practically of Free of tannins (see analysis) and can be used immediately for brewing purposes, provided that it is not preferred to mix it with the hop constituents obtained in the aqueous extraction.

The extracted hops are much lighter than before 2, the treatment and practically odorless. Especially this point is important for a subsequent aqueous extraction of the treated hops, since old the volatile components of the essential oil are no longer lost during water extraction and subsequent vacuum concentration

be able. . , λ. _

The hops freed from all of the resin and the essential oils can then be extracted in the known manner in the aqueous phase without any further pretreatment, the solution concentrated and the solution concentrated under inert gas in suitable mixers with the CO ₂ extractor

be united. ,.

In a further preferred process modification, the hops freed from total resin and essential oils by treatment with dry, supercritical CO ₂ cannot be processed directly with water, but first in a second step with now moist, supercritical CO ₂ (the gas flow is moistened in Container C.) In this way an extract fraction is obtained, the components of which, for example, already have a somewhat tannic character. The thus obtained, again either almost dry or water-containing extract is added to the extract obtained from the first step and then either used by itself or the extract portion obtained from the purely aqueous extraction (= 3rd step), the z. B. spray or freeze-dried, also added.

As already mentioned, the supercritical extraction must be carried out at pressures above pkrii., Gas and at temperatures above 1 _kr and gas. In practice, values above 100 atmospheres, preferably 150 to 400 atmospheres, are chosen for the pressure. With regard to the temperatures one depends on the thermal load capacity of the material, that is, one will choose the lowest possible temperatures, z. Example in the range between 32 to about 10O ⁰ C, preferably between 40 and 50 ⁰ C.

Examples

1. 1 kg of air-dry Hallertau hops were processed _{with dry CO 2} in the system according to the drawing under the following conditions:

Extraction pressure p _x = ■ - 315 atü,

Extraction temperature I ₁ - 50 ⁰ C,

Separation pressure p ₂ - 67 atü,

Separation temperature .... I ₂ = 25 ° C. Duration: 7 hours

Total amount of circulated CO ₂ : 49.6 kg.

Result

170 g of a water-containing, olive-green, pasty extract were obtained. The one left behind extracted hops were light yellow green and almost odorless.

• The freed from resin portions hop 3 hours by 101 of water in a water bath at 90 was then, without further pretreatment extracted to 95 ° C, filtered the spent grains, and the solution was concentrated in vacuo at 40 to 50 ⁰ C. bath temperature to syrupy consistency of the residue. Freeze drying gave 209 g of a light brown powder. This mass was then intensively mixed with the previously obtained CO ₂ extract under inert gas at room temperature, which resulted in 379 g of hop extract. The analysis of this gives the following table:

Table 1

determination Hop,
unprocessed extract Hop,
after
water
extrak
tion Water content,%
Total resin,%
Total soft resins,%
«-Acids, ° / o
0 acids, ° / _o
Hard resins,%
Tannins,% 9.9
13.9
12.6
5.2
7.4
1.3
4.1 13.2
33.2
30.8
13.8
17.0
2.4
3.8 5.33
2.1
1.4
<0, l
1.4
0.7
<0, l

Extraction temperature

Segregation pressure

Demixing temperature

= 45 ° C, p ₂ = 60 atmospheres, U = 45 ° C.

almost odorless. The analysis shows the following table:

Table 2

2. 1 kg of air-dry Hallertau hops were processed in the plant under the following conditions with dry CO ₂ :

Extraction pressure p _x = 400 atü,

Result

HOg of an almost anhydrous, olive-green, obtained pasty extract. The remaining extracted hops were light yellow and green

determination Hops ^
unprocessed extract Hop,
after
CO ₁ -
Extrak
tion Water content, ° / ₀
Total resins, ° / ₀
Total soft resins,%
"-Acids, ° / o
| 3-acids,%
Hard resins, ° / ₀
Degree of extraction of the
«-Acids,%
Degree of extraction of the
Total resins,%
Tannins,% 7.0
14.5
12.7
4.4
8.3
1.8
3.55 <1
98
87
33.8
53.2
11th
<0, l '6.9
3.6
1.5
under
the
To
know
border
1.5
2.1
100
76
4.2

3. 1 kg of air-dry Hallertau hops was processed _{with N 2 O in the plant under the following conditions:}

Extraction pressure p _x = 200 atü,

Extraction temperature I ₁ = 50 ⁰ C,

Segregation pressure /? _t = 70 atm,

Demixing temperature t _t - 25 ° C.

Result

150 g of a water-containing, olive-green, pasty extract were obtained. The one left behind extracted hops were light yellow green and almost odorless. The analysis shows the following table:

Table 3

determination

Water content, ° / ₀

Total resin,%

Total soft resin,%

«-Acids, ° / ₀

0 acids, ° / "

Hard resins, ° / ₀

Tannins,%

Hops, unprocessed

9.9

13.9 12.6 5.2 7.4 1.3 4.1

extract

33 66.5 64.6 28.4 36.2 1.9

Hops, according to N ₁ O-

extraction

5.9

2.75

1.84

0.17

3.3

0.9

4.5

1 sheet of drawings

Claims (5)

1 2 treber then, after damping to expel the Claims: contained solvent, a second extraction is subjected to water. Solvent and L Process for the production of hops water extracts are combined to the finished hop extract extracts by extraction of air-dry 5. In addition, the pure solution hops with solvents are also characterized by medium extracts, i.e. those largely free of tannins, because the hops with resin components are already used for brewing purposes and are supercritical in terms of pressure and temperature, which has been shown to be too high a CO ,, SF ₆ , CHF ₃ , CHF ₂ Cl, CF ₃ CI, CF ₈ = CH ₂ , particularly good foam stability of the beer, C ₃ f " ₈ , N ₂ O, ethane, ethylene alone or in mixed 10 while at the same time color, cold stability and counteracting are _{extracted with one another or with CO 2} and the taste differs only slightly from the beers that were produced with the resulting solution by lowering the extract containing tannin (H. the pressure to below the critical pressure S chi 1 farth , Mschr. Brauerei 18, 65-77, 1965) .. All processes known to date are liable 2. The method according to claim 1, characterized in that the common disadvantage is that the solvents draws that at extraction pressures from .den hops extracts as from the spent grains ent-100 works up to 220 atm. must be removed. This only works with the extract 3. The method according to claim 2, characterized in that it is incomplete because it is syrupy or pasty draws that the extract obtained is dealt with masses, the solvent residues only very much Another supercritical extraction at pressure 20 difficult to release. In addition, the chemical between 100 and 150 atmospheres. Influence of solvents on the hops constituents 4. The method according to claims 1 to 3, is unclear in many cases. At least it was and is characterized in that one with the detection or the removal of solution-dry, supercritical CO ₂ extracted hop medium residues in the extract with considerable technical fening, then a second extraction with 25 and scientific effort, since this is now moist, Point subject to supercritical CO ₂ because of the applicable purity laws and the extract obtained from it with which attention is to be devoted. Another disadvantage of extraction with dry, supercritical gas is that the extract is mixed together depending on the solvent used. Settlement of the extracts. 5. The method according to claims 1 to 4, 30 The present invention includes a method characterized in that one during the production of either tannin-free or Separating a temperature above the tannin-containing hop extracts, at which all table temperature. Disadvantages of the previous methods, such as solvent residues in the extract, formation of toxic substances, 35 different extract compositions etc. are closed. The invention is based on the observation that, with regard to pressure and temperature, supercritical CO _{2 is} a good and, moreover, completely healthy For a long time it has become an increasingly safe solution medium for which the hops are used for brewing purposes instead of resin components and essential oils. Use natural hops hop extract. This process according to the invention has a number of advantages, especially in terms of the price of hop extracts by extraction from the air, but also in relation to the process of dry hops with solvent is the technology of brewing and the quality of the beer. 45 marked that the hops are also referred to. In the meantime, a large number of CO ₂ , SF ₆ , solutions for the production of hop extracts that are _{supercritical to pressure and temperature are CHF 3} , CHF ₂ CI, CF ₃ Cl, CF ₂ = CH ₂ , C ₃ F ₈ , N ₂ O, which initially all the resin components and ethane, ethylene alone or in mixtures with one another, essential oils of natural hops extracted with organic or with CO ₂ and extracted from the resulting solution solvents. Here, the extract is obtained by lowering the pressure on below the turn halogenated hydrocarbons, such as separating the critical pressure,
_{ethylene chloride, carbon tetrachloride, trichlorethylene, The invention will hereinafter be referred to in more detail on the CO 2 which} is particularly preferred as extractants in addition to methanol, ethanol, acetone, η-hexane, etc., either alone or in mixtures with one another. Written, however, the other above can also primarily be extracted from the pure resin components and the gases mentioned, alone or in mixtures with essential oils of hops, but can also be used with the same success as with CO ₂ . Depending on the polarity and selectivity of the solvents, they should be pre-cleaned before use,
also partly tannins and the like. Some processes Extraction is also possible with liquid CO ₂ , also work with mixtures of organic but its dissolving power is lower than that of the solvent and ammoniacal, aqueous supercritical medium, which is also the case for the other solutions to resin components and tannins etc. in the above gases. However, this changes to extract one operation. Later processes dissolving power when transitioning to over-extracting also from the start with water, whereby the critical state is volatile and is then considerably larger than the aqueous isomerization products,
tends solution is used for brewing purposes. 65 In a preferred embodiment of the Often, however, work is carried out in such a way that in the first drive, which is explained by the drawing, Extraction step mainly or exclusively works as follows: the resin components are dissolved out and the hops- Valves 1, 2, 3 and 4 are open, all others