NL7905784A - CLASSIFIER FOR BEER. - Google Patents

Description

M »J * '! S *

Rosemarie Wilz — Pauls, born Pauls, in Basel, Switzerland

Clarifying agent for beer.

The invention relates to a clarifying agent for beer using gelatin and / or fish glue.

In the production of beer, its storage after the completed main fermentation up to the filling is an important work process. At this stage, different processes must occur in the beer. The residual extract not yet fermented in the main fermentation must be fermented as much as possible. The beer must enrich itself with carbon dioxide.

A flavor ripening process must take place. Due to the action of the cold during the storage process, unstable protein tannin compounds must be insolubilized and excreted in the cold. The turbid substances and micro-organisms present in the beer must separate from the beer, so that a largely pre-clarified beer becomes available for filtration.

According to newer insights, the first three processes mentioned during the storage are not necessarily tied to the storage cellar. It is customary in many breweries, for example, to trigger the final fermentation of the beer in the fermentation cellar.

The taste ripening is effected with greater or lesser success, for example by the choice of the fermentation temperature in advance. An enrichment with carbon dioxide can also only be carried out directly before the filtration or filling of the beer, by adding the carbon dioxide obtained during the fermentation process back to the beer.

The main function of the storage phase therefore remains the protein stabilization by cold and the clarification of the beer.

The protein stabilization itself can be accomplished by adsorbents, which are contacted with the beer, for example, in the form of fine powdery silica gel products during the final filtration. Of course, the efficacy of such adsorbents is generally more economical and sustainable in the whole stabilization process when the pre-stabilization has already taken place in the storage cellar, for example by the action of the cold, and in general the entire stabilization process. However, if this is not the case, compensation can be obtained by using. making larger amounts of adsorbents or other chemicals that improve beer stability. The main task of the storage process therefore remains the natural clarification of the beer.

The natural clearance of the beer in the storage cellar is particularly important for the brewer because it determines the smooth (smooth) course of the filtration process on the one hand and the costs to be incurred for this on the other. In modern, largely rationalized breweries, it is important that each of the different process steps of the beer preparation proceeds smoothly and with the same once-set throughput. Therefore, a modern brewery is in extremely great difficulty when, for whatever reasons, the usual filtering performance is not achieved. Furthermore, in the case of poorly clarified beers, the filtration costs can rise very considerably, namely due to an increased consumption of filter aids, due to increased labor costs and finally also due to the possibly existing necessity of having additional filters or separators ready for emergencies.

Modern brewing technology in no way meets this necessity for the clarification of the beer. On the contrary, this modern brewing technique causes many difficulties. On the one hand, these are caused by the shorter storage times, which of course no longer allow for the extensive clearance through natural sedimentation of the turbid substances as before. On the other hand, however, the deposition of these turbid substances in large-volume fermenters, in particular in upright cylindrical tanks with a height of up to 20 meters, is complicated.

The good clarification of the beer is of particular importance in the Federal Republic of Germany and the other countries, which only allow the use of adsorbents for stabilizing beer.

Namely, the most common adsorbents for the protein adsorption from the beer are very fine powders which already reduce the filter flow through a kieselguhr filter only because of their small particle size. When still poorly clarified beer is made available for the filtration, very special difficulties will arise due to a reduced filter throughput with a possibly not fully occurring stabilizing effect.

This difficulty has been frequently observed in recent years and has led to serious business failures in many breweries. Malts were brought into use, resulting in cold, unstable and poorly clarifying young beers. In view of the cold stability expected by consumers, it was forced to increase the amount of adsorbent used in the final filtration. The filter throughput, which was already reduced due to the poor beer clearance, was thereby further reduced.

The difficulty of the natural clearing of the beer in the storage cellar has been known for a long time. Known means are also known to accelerate this clearance ((1) Weinfurtner F .: Die Bierbrauereu, III. Band, Die Technologie der Garung, Das fertige Bier, 1963, Verlag Enke, Stuttgart (daselbst Seite 228); (2) De Clerck J .:

Lehrbuch der Brauerei, Band I, 1964, Versuchs- und Lehranstalt für Brauerei 20 in Berlin (daselbst Seite 664)). Glue-like clarifying agents which may be of animal or vegetable origin are common. The best known is the sturgeon bladder, also called fish glue, the effectiveness of which, according to De Clerck, is based on the approximately 77% gelatin contained therein. However, gelatin or glues of vegetable origin have also already been used as agents to accelerate the clarification of beer.

Of the known adhesive-like clarifying agents, only the sturgeon may be used in the BRD, but also only with top-fermented beer. Under-fermented beer, which is the predominant amount of beer production in the BED and where the pre-clearance 30 is of particular significance for the above reasons, should not use any of the known glue-like clarifiers.

However, even if the known glue-like clarifying agents were permissible in the production of bottom-fermented beer, they would only allow good filter throughput, thereby offering the brewer more leeway when using powdered adsorbents in the wash-up filtration, but they would allow 7905784

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4 simultaneous protein stabilization is not suitable.

It has also already been proposed to carry out the protein stabilization of beer, which is usually carried out with powdered adsorbents in the final wash-up filtration, in two stabilization steps, in that part of the adsorbent amount is already added in the storage cellar. There the adsorbent has sufficient time to unfold its effect and can be separated again by sedimentation during storage at the bottom of the tank. However, this method is not always successful because the powdery adsorbents are not always able to bind and drag the very finest cloud particles of the beer to the bottom of the tank.

Consequently, some stabilization is achieved, but no significant improvement in clearance and filter throughput is appreciated. It has even been observed that in particularly disposed beers the sedimentation, in particular of the very finest adsorbent particles, is retarded. This then leads to such a beer being even more difficult to filter than an untreated beer. No information has yet been obtained as to the causes of the observations mentioned here.

Objectively, the difficulty still had to be solved compared to the prior art to find a clarifying agent which accelerates the natural clarification of the beer, improves its filtration behavior and which also complies indefinitely with the requirements of the purity requirements, namely, it has an adsorbent effect, does not give soluble substances to the beer and neither the taste nor the smell of the beer changes.

The solution of the said difficulty to the clarifying agent for beer using gelatin and / or fish glue is that according to the invention the gelatin and / or the fish glue is fixed on a carrier material such that it is insoluble in the beer. In addition to solving the above-mentioned difficulty, the clarifying agent according to the invention offers the advantage that it also simultaneously increases the protein stability of the beer and is substantially free of water-soluble substances, ie satisfies the purity requirements.

7905784 BC -i '5

It is surprising that the adsorbents customary for the protein stabilization of beer are capable of quantitatively adsorbing gelatin and / or fish glue, insofar as the saturation limits are not exceeded, and irreversibly retaining such that 5 of the adsorbed gelatin and / or the adsorbed fish glue is not given to the beer, so that the new clarifying agent meets the purity requirements. It is even more surprising that the adhesive-like clarifying agents, gelatin and / or fish glue, bound to an adsorbent, also have a clarifying effect in this bound state and improve the filtration properties of the beer. According to the prior art, the beer clarifying action of these agents was based on their swelling and solution in water. Likewise, however, it was also not predictable that the adsorbents used as carrier bodies would retain their protein-stabilizing action despite their partial loading with gelatin and / or fish glue.

The beer clarifying agent according to the invention thus guarantees the solution of the abovementioned difficulties in the brewing industry, namely that with one and the same agent, which meets the purity requirements, simultaneously a clarification, an improvement of the filtration properties and a protein stabilization. of the beer is reached. The clarifying agent according to the invention is preferably used in the storage tank. However, it can also be used on the filter.

Suitable adsorbents within the meaning of the invention are those known for the protein stabilization of beer, for example fine powder silica xerogels, fine powder silica hydrogel, fine powder precipitated silica in the moist or dried state, bentonites, acid-activated bleaching earths moist or dried state, other natural or artificial silicates, in so far as they have adsorption properties, as well as activated carbon and natural mixtures of the said agents with one another.

The gelatin used for the clarifying agent according to the invention must of course meet the requirements for gelatin in terms of its purity. Gel of the so-called B-type, that is to say basically pretreated gelatin, 7905784 6 C'v can be used. In general, however, better results are obtained with gelatin of the so-called A-type, i.e. acid-pretreated gelatin. The gelatin content of a clarifying agent according to the invention naturally depends primarily on the adsorption capacity of the adsorbent used for the gelatin in question. The advantage is no more than 10%, and preferably less than 5%, based on the dry matter of the adsorbent.

Sturgeon bladder or fish glue is used analogously to gelatin. Here, too, the content should not exceed 10% based on the dry matter of the adsorbent.

Incidentally, however, the limitation of the amount of gelatin and / or fish glue used is simply derived from the adsorption capacity of the adsorbent used as carrier material. When more than the protein-stabilizing adsorbent can be used, adsorbents cannot be absorbed by the adsorbent in their entirety. An adsorbent not meeting the purity requirements then arises because the excess gelatin and / or fish glue remains soluble in water and thus remains soluble in beer.

In a further embodiment of the invention, the gelatin and / or the fish glue on the adsorbent is chemically cross-linked. This further embodiment of the invention also makes it possible to use not only adsorbents, but also other inert carrier materials, for example cellulose or kieselguhr, as the carrier material for the gelatin and / or the fish glue. The chemical cross-linking also ensures, under exceptional application conditions, that the gelatin and / or the fish glue, when they come into contact with the beer, can no longer be detached from the carrier material, preferably the adsorbent.

However, the invention also includes a clarifying agent for beer using gelatin and / or fish glue as a commercial product, characterized in that it consists of a fine powder mixture of gelatin and / or fish glue and a protein stabilizing agent known per se adsorbent, on which the gelatin and / or the fish glue can be fixed. The beer clarifying agent according to the invention is prepared and marketed in this form. The fixation of the gelatin and / or the fish glue on the adsorbent is only carried out in the brewery 7905784 # - * 7 by suspending the mixture in water.

The preparation of the beer clarifying agent according to the invention is simple. The methods described below are eligible.

According to a first embodiment, the method of preparing a clarifying agent for beer using gelatin and / or fish glue is characterized in that a suspension of a powdery, protein-stabilizing adsorbent is contacted with a solution of gelatin and / or fish glue, after which the mixture is left to stand for some time with occasional stirring. Within a time period of maximum 15 minutes, the gelatin and / or the fish glue, if no excess is added, is bound quantitatively and irreversibly to the adsorbent.

In order to investigate whether this is actually the case, the following test can be used. The suspension is centrifuged after the contact time. 1 ml of 50 Z's sulfuric acid as well as 1 ml of a solution of 50 g of sodium molybdate in 100 ml of water are added to 10 ml of clear centrifugate. The presence of excess gelatin and / or fish glue leads to cloudiness. The detection limit of this test is 2 mg gelatin in 100 ml water.

A further variant of the embodiment consists in that fine powder gelatin and / or fine powder fish glue is mixed with fine powder adsorbent and, if necessary, the mixture is again subjected to a very fine grinding for further homogenization thereof.

According to a further embodiment of the invention, the method for preparing a clarifying agent for beer using gelatin and / or fish glue is characterized in that the gelatin and / or the fish glue is incorporated therein during the preparation of the protein stabilizing adsorbent. . Thus, the gelatin 30 and / or the fish glue in the form of a concentrated solution or also as a powder in silicic acid hydrogel or acid-activated, washed, undried bleaching earth, may preferably be incorporated in a kneader and the mixed product then dried and dried. and grinding are subjected.

Finally, in certain cases, namely when the chosen protein stabilizing adsorbent, the selected gel may be used 7905784 3. ¾ 8 tine and / or the chosen fish meal does not bind irreversibly, it is necessary to chemically cross-link the gelatin and / or the fish glue on the carrier material. This can be done with formaldehyde or glutardialdehyde. Of course, other known methods of curing gelatin can also be used within the scope of this invention.

The invention is further illustrated but not limited by the following examples which describe the preparation, use and operation of the clarifying agent of the invention using gelatin as the adhesive-like clarifying agent. When using fish glue, analogous methods as described in the examples are used.

Example I

Determination of the maximum amount of gelatin.

10 g of finely ground silica xerogel are weighed into several 100 ml shaking cylinders. About 50 ml of water are added and the silica gel is suspended therein. Increasing amounts of a 2% Ts gelatin solution in water are then added, so that the weighed 10 g of silica gel contains 50, 100, 200, 300, 400, 600 and 800 mg of gelatin. It is made up to 100 ml of liquid with water, shaken and the mixture is left to stand for 30 minutes with shaking now and then. Then, about 30 ml of the suspension is centrifuged off and the clear centrifugate is examined for gelatin not adsorbed on the silica gel using the test described above.

Result: 25 10 g silica gel + 0 mg gelatin negative 10 g silica gel + 100 mg gelatin negative 10 g silica gel + 200 mg gelatin negative 10 g silica gel + 300 mg gelatin negative 10 g silica gel + 400 mg gelatin negative 30 10 g silica gel + 600 mg gelatin positive 10 g silica gel + 800 mg gelatin positive

The test shows that the silica gel used adsorbs irreversibly up to 4% gelatin.

The adsorption capacity of 35 other eligible adsorbents is determined in the same manner.

The amount of gelatin required for the treatment of a particular beer varies from case to case and can be determined by clarification and stabilization tests (see further examples). There is a tendency that the clarifying action of the combined adsorbent becomes all the better the more gelatin is used with respect to the carrier adsorbent. On the other hand, the protein-stabilizing effect of the carrier product is only slightly reduced.

Example II

For the clarification and simultaneous protein stabilization of a particular beer, the application of silicic acid xerogel with 2% gelatin has been shown to be optimal in a small-scale test. For the beer treatment in the brewery, the required amount of silica gel is suspended in water. The amount of gelatin amounting to 2% of the silica gel weight is dissolved in hot water and this solution is then added to the silica gel suspension. After 15 minutes, the mixture can be used for the beer treatment.

Example III

98 kg of a fine-powdered dry, acid-activated bleaching earth according to DOS 2,247,530 are intimately mixed with 2 kg of a finely ground consumer gelatin, the particle size of which is below 100 mesh. This mixture can be suspended in water without difficulty. The gelatin dissolves without difficulty and is adsorbed directly by the bleaching earth.

Example IV

98 parts of a granular, large-pore ("whey pore") silica xerogel is mixed with 2 parts of coarsely ground gelatin. This mixture is ground to the finest possible powder with the aid of a high-speed pin mill. This finest powder, too, can be suspended in water without difficulty, the gelatin dissolving and being adsorbed directly on the silica gel.

Example V

Acid-activated bleaching earth according to DOS 1,642,767 is used, as it comes out of the filter press after the washing process.

In this state, the filtered material contains 33% dry matter.

300 kg of this filtered material (corresponding to 100 kg of dry matter) are intimately mixed in a kneader with a solution of 2 kg of gelatin in 10 liters of hot water. It is then dried and ground to a fine powder in the usual manner.

Example VI

500 g of a silica hydrogel 5 are suspended with 40% dry matter in 2 liters of water. 5 g of gelatin dissolved in 100 ml of water are added. After 15 minutes with stirring occasionally, 20 ml of a 35% formalin solution are added. The mixture is kept in a sealed vessel at 80 ° C for 16 hours. The hydrogel is then filtered off, washed with water, then dried at 100 ° C and ground.

The same mixture is prepared, adding 20 ml of a 25% glutardialdehyde solution instead of the formaldehyde. In the products mentioned here, the gelatin was cross-linked to the adsorbent and thereby additionally rendered insoluble.

The gelatin amount on the dry silica gel dust here was 2.5%. Example VII

Clarification effect of the products according to the invention. A fine powder silica xerogel with 2% gelatin prepared according to Example IV was used, and the same xerogel without gelatin was compared therewith. Also a fine powder dry bleaching earth according to DOS 2,247,530 with 2% gelatin, prepared analogous to example IV, and the same bleaching earth without gelatin were used. In addition, the clearing action of gelatin alone was also observed. 20 mg per liter of beer in the form of a 1% aqueous solution was used.

The adsorbents were stirred with water before use to form a 10% suspension. Freshly pumped lager from a Munchener brewery from the storage cellar was filled into 1 liter beer bottles. To this beer are added 50 g / hl 30 of the adsorbent according to the invention in the form of the aqueous suspension and 2 ml of the 1% gelatin solution, respectively. Gelatin alone is therefore used twice as much as was used per liter of beer with the adsorbents according to the invention. The beers are now stored at 0 ° C. The progressive clearance is monitored in a turbidimeter. The results are shown in the table below.

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Cloudiness after ..... days (EBC units) 1_3_5_7_ 0 - Beer »15» 15 »15> 15

Silica gel without gelatin »15» 15 »15> 15 5 Silica gel with 2% gelatin» 15> 15 7.5 6.0

Bleaching earth »15» 15 »15> 15

Bleaching earth with 2% gelatin »15> 15 8.1 6.4

Gelatin »15» 15> 15 approx. 12

The results indicated in the table above 10 show that, during the 7-day storage of the sample beers, although the 0-beer was clarified slightly, after 7 days the haze was still more than 15 EBC units and not exactly in the measuring device could be determined. The same applies to sample 2, which contained 50 g / hl of silica xerogel, and also to sample 4 with 50 g / hl of bleaching earth.

On the other hand, sample 3 appears to have a very significant acceleration of clearance. Already after 3 days, this sample clearly distinguished itself from the 0 beer. After 5 and 7 days, extensive clearance had already occurred. Analogous results were also obtained in sample 5 using bleaching earth with 2% gelatin. The gelatin alone causes only a slight acceleration of the clearance.

Example VIII

The above samples were also subjected to a laboratory scale filtration after observation of the clearance for 7 days. To this end, a method described in Monatsschrift für Brauereu 21, 277-285 (1968) was used, which makes it possible to express the filtering capacity of a beer in exact numbers. The filter cake factor was determined. The higher this factor, the slower the filtration. The results indicated below were obtained for the six sample beers.

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Filter cake factor 0-Beer 0.340

Silica gel without gelatin 0.374

Silica gel with 2% gelatin 0.284 5 Bleaching earth 0.452

Bleaching soil with 2% gelatin 0.305

Gelatin 0.350

From the results indicated above, it appears that the O beer had a filter cake factor of 0.340. In sample 2 with the fine powder silica gel, an increase of this filter cake factor by about 10% is obtained. The filtration is also somewhat delayed here. Sample 3 according to the invention, on the other hand, shows a filter cake factor drop of the order of 20%. Sample 4 with bleached earth ground as finely as possible filters considerably slower than the 0 beer; the filter cake factor increased to 0.452. The sample 5 according to the invention, on the other hand, clearly filtered better than the O beer. The sample with gelatin was about equal to the O beer in terms of its filtration behavior.

Example IX

The sample beers filtered in the previous example were collected under a cooling acid atmosphere and subjected to a forced test. After a storage period of 3 days at 40 ° C and 24 hours in melting ice, the increase in cold haze was as indicated in the table below.

25 Cloudiness in the cold after 3 warm days 0-beer 8.1

Silica gel without gelatin 3.1

Silica gel with 2.9% gelatin 2.9

Bleaching earth 2.1 30 Bleaching earth with 2% gelatin 2.4

Gelatin 7.5

These results show that the adsorbents of the invention had approximately the same protein stabilizing action as the untreated materials without gelatin. Sample 3 appears to be somewhat more stable than sample 2. Comparing samples 4 and 5, the reverse appears to be the case. However, the differences are 7905784 13 small. Sample 6, using only the gelatin, was only slightly better in stability than the O beer.

Sample beers 1, 2 and 3, i.e. the 5 O beer, the silica gel-treated beer and the beer treated with the silica gel and gelatin product of the invention, were also investigated for whether gelatin in the beer had gone into solution.

To this end, samples from the three beers were first hydrolyzed with acid and then tested for hydroxyproline. This amino acid is an essential building block of gelatin. It appeared that no difference in hydroxyproline was observed in all three beers, and this means that no gelatin was released from the product according to the invention during contact with beer. This confirms the above observation that silica gel and also bleaching earth in aqueous suspension absorb a certain amount, up to about 5%, of gelatin and retain it irreversibly by adsorption. This irreversible adsorption is also guaranteed under the other beer conditions (pH, ionic strength, etc.), so that the silica gel or bleaching earth product with gelatin according to the invention meets the purity requirement.

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Claims (10)

Clarifying agent for beer using gelatin and / or fish glue, characterized in that the gelatin and / or the fish glue is fixed on a carrier material such that it is insoluble in the beer. Clarifying agent according to claim 1, characterized in that the gelatin and / or the fish glue is adsorptively fixed on a per se known protein stabilizing adsorbent. Clarifying agent according to claim 1, characterized in that the gelatin and / or the fish glue is fixed on an inert carrier material, for example cellulose or kieselguhr, by chemical cross-linking. Clarifying agent for beer using gelatin and / or fish glue, characterized in that it consists of a fine powder mixture of gelatin and / or fish glue with a protein stabilizing adsorbent known per se, on which the gelatin and / or the fish glue is fixable. Process for preparing a clarifying agent as defined in claim 1, characterized in that a suspension of a powdery protein-stabilizing adsorbent is contacted with a solution of gelatin and / or fish glue and the mixture is occasionally stirring for some time. 6. Process for preparing a clarifying agent as defined in claim 1, characterized in that dry ground gelatin and / or dry ground fish glue and a ground adsorbent are mixed together, this mixture is stirred to form a suspension and this for some time. let alone time. Process for the preparation of a clarifying agent as defined in claim I, characterized in that gelatin and / or the fish glue are incorporated therein during the preparation of the protein-stabilizing adsorbent. Process for the preparation of a clarifying agent as defined in claim 2, characterized in that the gelatin and / or the fish glue on the carrier material is chemically cross-linked. Process for the preparation of a clarifying agent as defined in claims 2 and 7, characterized in that the gelatin 7905784 tine and / or the fish glue is chemically cross-linked with formaldehyde or glutaraldehyde on the carrier material. Beer obtained using the clarifying agent according to claims 1-4. 7905784