MXPA99000553A - Method for producing cold-filtered beer - Google Patents

Abstract

The invention relates to a method for producing cold-filtered beer. According to said method, beer is filtered through a membrane filter which is able to absorb calcium ions. After filtration, said membrane filter is cleaned and rinsed with aqueous substances. The washed and rinsed membrane filter can then be reused. The invention is characterised in that an acidic aqueous substance with a pH less than 5.0 is used for rinsing, or in that the substance used for rinsing is treated in order to reduce the quantity of calcium ions it contains. The inventive method provides a means of producing beer with less tendency to gush.

Description

METHOD TO PRODUCE BEER FILTERED IN FRIÓ FIELD OF THE INVENTION The present invention relates to a method for producing beer filtered in cold, in which beer is filtered through a membrane filter that is capable of absorbing calcium ions, and which is cleaned and rinsed with aqueous medium after filtration. , after which the clean and rinsed membrane filter is used for a new filtration.

BACKGROUND OF THE INVENTION Due to the extended marketing channels, germs have to be removed from the beer to make it storable. Currently, beer is mainly pasteurized for the elimination of germs. For this purpose, beer, for example bottled or canned, is heated to a temperature between 62 and 68 ° C, which destroys germs. However, this pasteurization includes a considerable energy consumption. It has the additional disadvantage that the energy supplied can activate chemical reactions that deteriorate the product and are difficult to control. These reactions can adversely affect for example the taste of the product ("pasteurized flavor") and there is also the danger that unwanted substances are formed. In this way, pasteurization is a relatively expensive method of eliminating germs that involves high energy expenditure and consequently, has harmful effects on the environment and occasionally reduces the quality of the product. As an additional germ removal method, cold filtration is known. Cold-filtered beers are offered as "draft beers", for example in the United States of America, Japan and Korea. In Europe, these beers are banned because they contain technical enzymes. With these technical enzymes, a disadvantage of the cold filtration inherent in this technique is counteracted: the rapid clogging of the filter. This obstruction is due to the deposits of the substances separated by filtering the beer on the inlet side of the membrane filter. It is difficult or impossible to remove filter deposits, and filter life is reduced. This increases the cost of beer production, since membrane filters are expensive. To prolong the filter life, membrane filter manufacturers recommend cleaning used membranes by treating them with proteases, glucanases and xylanases, as well as chemical agents such as surfactants, acids / bases, and oxidizing agents, making them reusable. This cleaning can be carried out, for example, in two stages, where in a first cleaning step it is done with the enzymes mentioned, followed optionally by additional cleaning with the mentioned chemical agents. An exemplary cleaning procedure, for example for a filter area of approximately 320 m, includes enzymatic cleaning after every 5,000 hectoliters (hl) filtered and additional chemical cleaning after every 20,000 hectoliters filtered. The typical duration of the filters 0 with the mentioned filter area subjected to said cleaning is approximately 100,000 hectoliters (hl). It is known that, after being subjected to a first cleaning procedure, some types of filter ? membrane immediately after cleaning, filter a beer that, bottled or canned, tends towards the so-called "gurgling" It is known that the term "bubbling" denotes a spontaneous foaming above the beer when the bottle or can is opened. By doing so, carbon dioxide 0 escapes suddenly, accompanied by such strong foaming that the bottle or can is emptied in a more or less large amount. It is evident that the customer considers the propensity to "bubbling" as a defect of the product, which can lead to serious economic disadvantages for the brewer.

The exact reason for the occurrence of gurgling is unknown. It is assumed that bubbling is related to the raw materials used for the production of beer. Low molecular weight compounds, for example fatty acids, bitter substances of the hops, polypeptides, oxalic acids and substances derived from an infection with fungi, are considered as the so-called "bubbling promoters". In addition, it is known that membrane filtration can reduce the propensity to gurgle. However, membrane filters have different pore sizes, which leads to different results.

DESCRIPTION OF THE INVENTION According to the applicant's experience, the propensity to gurgle is particularly strong with beers that are filtered thh certain freshly cleaned membrane filters. This is particularly pronounced with membrane filters made at least partially of polyamide. Therefore, the object of the invention is to provide a method for producing cold filtered beer, in which the filtration works by means of membrane filters and, nevertheless, the propensity to bubbling of the filtered beer immediately after a cleaning process at least it is reduced. The method according to the invention of cold-filtered beer production, wherein the beer is filtered thh a membrane filter which is able to absorb calcium ions and is cleaned and rinsed with aqueous medium after filtration, after which the clean and rinsed membrane filter is used for a new filtration, characterized in that for rinsing an aqueous acidic medium having a pH of less than 5.0 is used, or because the medium used for rinsing is subjected to a treatment intended for to the reduction of the calcium ion content. The invention is based on the knowledge that the The tendency towards bubbling is particularly strong if the beer is filtered thh a membrane filter capable of absorbing calcium ions. This is the case, for example, if the filter is made at least partially of polyamide. If after cleaning said filter is rinsed with an aqueous medium, For example, tap water containing calcium ions is absorbed in such a way that the filter is charged with calcium ions. If said filter loaded with calcium ions is used ) for a new beer filtration, these calcium ions are released again by the filter at the beginning of the filtration due to the acidic pH of the beer to be filtered. In this way, these calcium ions enter the beer. The Applicant considers that when carboxylate anions are present in beer, for example oxalate, the liberated calcium ions form fine crystals acting as seeds for the formation of CO2 gas bubbles • It has now been shown that the bubbling propensity can be traced back to the initial release of calcium ions from ^ the newly cleaned filters. In this way, the acid rinse according to the invention serves to wash and remove again the calcium ions absorbed by the membrane filter during the cleaning procedure. If it is used to clean and rinse an aqueous medium subjected to a treatment aimed at reducing the content of calcium ions, ie a decalcification for example 10 by means of ion exchangers, the cold rinse acid according to the invention is unnecessary. . Also in this case, the beer that is filtered thh a freshly cleaned filter does not show propensity to gurgle. Conveniently, the acidic aqueous medium has a pH of less than 4.5, preferably between 3.0 and 4.0 and, in particular, less than 3.5. For adjusting the pH, an organic acid, in particular lactic acid, is conveniently used. In addition, the invention relates to a method for producing cold filtered beer, wherein the beer produced from malt, hops and water, is subjected to a membrane filtration, and is characterized in that water subjected to a treatment is used. aimed at reducing the content of calcium ions to produce beer. The invention can be applied to all membrane filters that bind calcium ions. This is for example the case with a membrane filter made at least partially of polyamide. It is assumed that the polymer comprises free carboxylate gs or similar reactive gs capable of binding calcium ions. In the following, the invention is described in greater detail. For membrane filtration, a polyamide membrane filter usually used in the prior art was employed. After filtering, the filter was cleaned first enzymatically and then chemically, the next? way: For enzymatic cleaning, the clogged filter was treated for 1 hour with a 1% aqueous solution of a mixture of ß-glucanases and xylanases (P3-Ultrasil 65, manufacturer: Henkel) having a pH of 5 (adjusted by medium of a 0.05% aqueous solution of a mixture of surfactants and an acid component (P3-Ultrasil 75, manufacturer: Henkel) at a temperature of 50 ° C. Then, this treatment was repeated. 3 hours with a 0.5% aqueous solution of a mixture of surfactants, glucanases and proteases (P3-Ultrasil 62, manufacturer: Henkel) having a pH of 9 to 9.5 (adjusted by means of a 0.15% aqueous solution of a mixture of surfactants and an alke component (P3-Ultrasil 91; manufacturer: Henkel)) at a temperature of 50 ° C and then rinsed with lukewarm tap water (50 ° C).

For chemical cleaning, the filter was treated during minutes with a 1% aqueous solution of a mixture of ^ surfactants and an acid component (P3-Ultrasil 75, manufacturer: Henkel) at 60 ° C and then rinsed with water new stream. After this, the filter was treated for 30 minutes with an aqueous solution containing 1% of a mixture of surfactants and an alke component (P3-Ultrasil 91, manufacturer: Henkel) and 1% of a mixture of surfactants and a oxygen donor (P3 -Ultrasil 05, manufacturer: Henkel) a a temperature of 60 ° C and then rinsed with running water? new. The filter was then treated again for 30 minutes with a 0.5% aqueous solution of a mixture of surfactants and an acid component (P3-Ultrasil 75, manufacturer: Henkel) and then rinsed with running water. new until the rinse water has obtained the electrical conductivity of the new water. The water used for cleaning and rinsing the membrane filter f used was in each case non-decalcified running water. It has been shown that the beer that was initially filtered through this membrane filter cleaned according to the above method exhibited a propensity towards bubbling. It was only in a filtering amount of approximately 0.8 hl or more of beer per square meter of filter area, and having finished the release of calcium, which could be filtered again beer without propensity to gurgle. If the same filter cleaned according to the above method was rinsed with water whose pH had been adjusted to 4.5 by the addition of lactic acid, it was shown that the rinse water was enriched with calcium ions, apparently coming from the membrane filter recently. cleaned. The beer that had been filtered through this membrane filter rinsed with acid rinse water, did not exhibit propensity to gurgle. The same effect could be observed when decalcified water was used to clean and rinse.

Claims (7)

NOVELTY OF THE INVENTION CLAIMS

1. - A method to produce cold filtered beer, in which beer is filtered through a membrane filter that is capable of absorbing calcium ions, and cleaned and rinsed with aqueous medium after filtration, after which The cleaned and rinsed membrane filter is used for a new filtration, characterized in that an acidic aqueous medium having a pH of less than 5.0 is used to rinse, or the medium used for rinsing is subjected to a treatment aimed at reducing the content of calcium ions.

2. A method according to claim 1, characterized in that the acidic aqueous medium has a pH of less than 4.5.

3. - A method according to any of claims 1 or 2, characterized in that the aqueous medium has a pH between 3.0 and 4.0, in particular less than 3.5.

4. - A method according to any of claims 1 to 3, characterized in that the acid aqueous medium used for rinsing contains an organic acid.

5. A method according to claim 4, characterized in that the acid contained in the acidic aqueous medium is lactic acid.

6. - A method for producing beer filtered in cold, where the beer produced from malt, hops and water, is subjected to a membrane filtration, characterized in that water subjected to a treatment aimed at reducing the content of calcium ions is used for the production of beer.

7. - A method according to any of claims 1 to 6, characterized in that a membrane filter made at least partially of polyamide is used.