WO1999006527A2

WO1999006527A2 - Agent for producing and/or processing alcoholic beverages, in particular wine or sparkling wine, and use of said agent

Info

Publication number: WO1999006527A2
Application number: PCT/EP1998/004726
Authority: WO
Inventors: Holger LÖWE; Rainer Pommersheim
Original assignee: INSTITUT FüR MIKROTECHNIK MAINZ GMBH
Priority date: 1997-07-30
Filing date: 1998-07-29
Publication date: 1999-02-11
Also published as: DE19834262A1; WO1999006527A3; EP1002048A2

Abstract

The invention relates to an agent used in the production and/or processing of alcoholic beverages, in particular wine or sparkling wine. This agent is composed of microcapsules which each have an enveloping membrane that encloses the capsule interior completely. The capsule interior contains cells of at least one species of micro-organism, such as yeast or lactic acid bacteria, and/or one or more enzymes. The invention seeks to produce microcapsules having the following characteristics: ability to permanently immobilize the cells or enzymes; presence of enveloping membranes with adjustable transparency and mechanical stability, in accordance with need; liquefiable content of the microcapsules. To this end, the envelope membrane is composed of at least two radially superimposed layers. Each layer encloses all the layers arranged beneath it completely. The invention also relates to the use of this agent in the production of beer and low-molecular alcohols.

Description

Agents for the production and / or treatment of alcoholic beverages, in particular wine or sparkling wine, and their uses

description

The invention relates to an agent for the production and / or treatment of alcoholic beverages, in particular wine or sparkling wine, according to the preamble of the main claim and to the uses thereof.

Different species of microorganisms, in particular yeasts, are used for alcoholic fermentation in the production of alcoholic beverages, in particular wine or sparkling wine. To optimize the results, further species of microorganisms and enzymes are added to the product or precursors thereof. For example, lactic acid bacteria are used to break down malic acid and pectinases to accelerate must clarification.

The process of alcoholic fermentation can be interrupted by measures such as rapid cooling, the addition of sulfur dioxide or filtration. However, these methods of inactivating the yeast are complex, can only be controlled with imprecision and can impair the quality of the product. This means that the use of different species of yeast at different times is costly.

After treating a wine with lactic acid bacteria, for example, to reduce the acidity, the added microorganisms have to be separated, which takes place in the comparatively small lactic acid bacteria via membrane filtration. However, complete removal of the microorganisms is not always guaranteed. Lactic acid bacteria remaining in the wine can convert glucose to acetic acid and thus spoil the wine.

Enzymes, such as proteases to break down peptides and proteins, are added to the product or precursors thereof in liquid form. The inactivation of enzymes is usually carried out by heating, which can be associated with an impairment of the product and a reuse of the sometimes expensive enzymes. Bottle fermentation agents in sparkling wine production are known which consist of yeasts immobilized in alginate beads (G. Troost et. Al., Sekt, Sparkling Wine, Perlwein, Stuttgart 1995 and DE 39 08 997 A1). With this, the time-consuming manual shaking of the fine yeast deposit could be replaced by the rapid sinking of the alginate beads in the champagne bottle. A disadvantage of such agents, in which the beads are not surrounded by a cell-free envelope membrane, is, however, that they do not have a high mechanical stability and cannot sufficiently prevent outgrowth, in particular relatively small microorganisms, so that microorganisms remain in the product after the beads have been separated off can. Multiple use of such funds is therefore difficult to implement. Furthermore, due to their small size, enzymes cannot generally be immobilized in such alginate beads.

No. 4,996,150 describes a process for the microencapsulation of biocatalysts, preferably yeasts, and their use for the continuous production of ethanol. The biocatalysts are contained in a matrix of an anionic polysaccharide and a cationic polymer. Here, too, the microcapsules do not have a cell-free envelope membrane, so that yeast outgrowth cannot be adequately prevented. In addition, a sufficiently safe immobilization of smaller biocatalysts, such as enzymes, is hardly possible.

US 4,659,662 describes a process for producing alcoholic beverages or bioalcohol using microcapsules containing yeast. The yeasts can be embedded in a matrix material which is additionally surrounded by an envelope membrane which, however, is identical to the matrix material. Yeasts immobilized in calcium alginate are mentioned as an example. However, the envelope membrane consists of only one layer and is also permeated by cells, i. H. not cell-free. Outgrowth of the yeasts can therefore not be prevented sufficiently and immobilization of enzymes with sufficient long-term stability is hardly possible.

DE 34 32 923 C2 relates to biocatalysts with immobilized cells which are surrounded by a single-layer, cell-free envelope membrane. The envelope membrane surrounding the interior of the capsule and not permeable to the cells can consist of an ionically or covalently crosslinked gel. Sparkling wine production is cited as an example of use. The envelope membrane preferably consists of the same substance as the matrix material in the interior of the capsule. For this purpose, the crosslinking agent, for example calcium ions, beads which are present in excess, here made of calcium alginate, are again added to a cell-free substance which forms the envelope membrane, here an alginate solution. The disadvantage here is that liquefaction of the capsule contents is not possible without dissolving the envelope membrane. In the case of enzymes in particular, however, a liquefied capsule interior enables the natural conformation and thus the activity of the enzyme to be retained. In addition, with such envelope membranes, the requirements, such as targeted adjustability of the permeability and a sufficiently high mechanical stability, can hardly be achieved.

The object of the invention is to provide a means for producing and / or treating alcoholic beverages, in particular wine or sparkling wine, according to the preamble of the main claim, in which the cells or enzymes are permanently immobilized, in which the permeability and the mechanical stability of the envelope membrane can be specifically adjusted, and the content of the microcapsules can be liquefied.

Furthermore, the invention has for its object to show uses of the agent according to the invention.

The object is achieved by means having the features of claim 1 and by the uses according to claims 20 and 21, the subclaims relating to advantageous embodiments of the invention.

The species of microorganisms and / or enzymes used for the production and / or treatment of alcoholic beverages, in particular wine or sparkling wine, are immobilized in that they are contained in the interior of a microcapsule and in that an envelope membrane completely surrounds the interior of the capsule. Leakage of the microorganisms or enzymes is prevented by the fact that the envelope membrane is not permeable to these microorganisms or enzymes. In order to ensure the conversion of a substance, the envelope membrane is for the substances to be converted (educts), which also include the nutrients necessary for the microorganisms, for example glucose, and for at least some of the generated or converted substances (products), such as alcohol and carbon dioxide, permeable. The requirements for permeability and mechanical stability are met by an envelope membrane which has at least two layers arranged radially one above the other, each layer completely enclosing all layers arranged radially below it. The individual layers are advantageously connected to one another ionically and / or covalently.

Only this multi-layer structure allows the permanent immobilization of the cells or enzymes for the production and / or treatment of alcoholic beverages, such as wine or sparkling wine. This effectively prevents yeast outgrowth and the associated destruction of the microcapsules. Due to the high mechanical stability, the microcapsules can also be used in larger bioreactors without the microcapsules being crushed or bursting. This increased stability also enables the interior of the capsule to be liquefied without the microcapsules becoming mechanically unstable as a result. In addition, the permeability of the envelope membrane can be set in a targeted manner by a suitable selection of the at least two layers, which is of crucial importance for the immobilization of enzymes.

Not only the outer layers, but also the innermost layer of the envelope membrane preferably do not have any of the cells or enzymes contained in the interior of the microcapsules.

At least two layers of the envelope membrane preferably consist of different substances. For example, an outer layer (support layer) can consist of a substance that ensures a high mechanical stability of the microcapsules, while an inner layer (regular layer) consists of a substance that enables a targeted adjustment of the permeability of this layer and thus the envelope membrane.

According to an advantageous embodiment, the cells or enzymes contained in the interior of the microcapsule are embedded in a matrix. This matrix can be constructed from an alginate compound of a polyvalent cation, for example calcium, strontium, barium, aluminum and / or iron.

According to another advantageous embodiment, the cells or enzymes are freely movable in a liquid inside the microcapsule, which is particularly advantageous for maintaining the natural conformation of the enzymes. As a result, the natural activity of the cells or enzymes is retained despite the immobilization. If the microcapsules are produced by precipitation of drops of a solution containing the cells or enzymes using a crosslinking agent, the interior of the capsule can be liquefied again after the layers of the envelope membrane have been applied. If the substance of the matrix inside the capsule consists of calcium alginate, for example, the polyvalent metal cation can be exchanged for monovalent cations, for example sodium or potassium, in order to liquefy the interior of the microcapsule again. It is therefore preferred that at least one layer of the envelope membrane consists of a substance different from the substance embedding the cells or enzymes and forming the matrix. In known microcapsules, the single-layered envelope membrane of which consists of the same substance as the matrix in the interior of the capsule, this liquefaction of the interior of the capsule is not possible, since the envelope membrane would also dissolve here.

When using a substance which can be crosslinked by means of polyvalent cations, for example alginate using calcium, the exchange of the polyvalent cations for monovalent cations is furthermore advantageous in that polyvalent cations, such as calcium, are generally undesirable in wine production. For example, a matrix of calcium alginate can be liquefied by introducing the microcapsules into an aqueous solution containing sodium citrate, which causes the calcium ions to be exchanged for sodium ions. These microcapsules, used for example in wine production, preferentially bind multivalent ions from the substrate to be reacted, such as grape juice, which has an advantageous effect. If the matrix of these microcapsules again has an excessively high content of polyvalent cations, treatment with a solution containing monovalent cations can regenerate it.

Microcapsules with an envelope membrane both from one layer and from several layers are known in medicine for immobilizing cells or enzymes. For example, Langerhans cells were enclosed in a microcapsule, the envelope membrane of which was composed of a layer consisting of alginate and poly-L-lysine (F. Lim et. Al., Science, 210 (1980) 908-910). In EP-A-681834 microcapsules, the shell membrane of which is composed of several layers, for insertion into tissue of living beings described. Such microcapsules place demands on tissue compatibility, a low immune response and on the replaceability in living tissue.

By optimizing the structure of microcapsules with a multi-layered envelope membrane with regard to the production or treatment of alcoholic beverages, corresponding microorganisms, such as yeasts or lactic acid bacteria used in alcoholic fermentation, and / or enzymes can be immobilized. _, In particular, it must be ensured in the immobilization of yeasts for fermentation stability despite the production of carbon dioxide and a rapid growth of the yeast cells. This is achieved by means of microcapsules with enveloping membranes which have at least two layers arranged radially one above the other.

The agent according to the invention has the advantage over agents known in the manufacture of alcoholic beverages that the enclosed cells or enzymes are permanently immobilized and, due to the simple handling, can be added in a convenient dosage and can also be easily, quickly and completely removed from the product. This makes it possible to influence the individual production steps in a targeted manner without impairing the quality of the product. In addition, the cells or microcapsules containing enzymes can be reused, which leads to cost savings, in particular in the case of expensive enzymes. Furthermore, due to the voids present between the capsules even in the case of sedimented microcapsules and the easy mobility of the microcapsules in a liquid, a good mass transfer, in particular gas exchange during alcoholic fermentation, is ensured.

It can be advantageous to make the envelope membrane impermeable to active substances and / or microorganisms located outside the microcapsule which could impair the activity of the cells or enzymes contained in the interior of the capsule. For example, some species of yeast used in winemaking produce toxins that are harmful to other species of microorganisms. By using microcapsules, the envelope membrane of which is not permeable to such toxins, such microorganisms or enzymes can be used together in, for example, wine production. According to a preferred embodiment, the microcapsules contain as microorganisms at least one yeast species used in wine production.

According to a further preferred embodiment, the microcapsules contain at least one species of lactic acid bacteria, which are used in the biological acid degradation for wine treatment.

Methods for deacidifying wine using cells of the species Leuconostoc oenos immobilized in calcium alginate are known from US Pat. No. 4,380,552. However, these beads do not have an envelope membrane, so that sufficient stability and cell outgrowth are not guaranteed.

Microcapsules which contain enzymes used in particular in wine or sparkling wine production, such as pectinases, glucanases, β-glucosidases, proteases and / or glucose-fructose isomerases, are advantageously suitable as agents for the production or treatment of alcoholic beverages.

It can be advantageous to immobilize both cells and one or more enzymes in a microcapsule. On the one hand, this can make handling easier, on the other hand it can increase productivity in particular if a product of the microorganisms or enzymes is further converted by the other microorganisms or enzymes contained in the microcapsule. Species of yeasts used in wine production and their treatment materials, such as yeast cell wall preparations and / or glucose-fructose isomerases, can thus advantageously be immobilized together in a microcapsule. In addition to increasing the activity of the yeasts used, the quantities of the sometimes expensive treatment substances to be used can be reduced.

The activity of the immobilized cells or enzymes increasing enzymes can also be included in a microcapsule. For example, it is known that the activity of lactic acid bacteria decreases with increasing acidity. By including a cation exchanger in a microcapsule containing lactic acid bacteria, the pH value can be determined at the location of the lactic acid bacteria by replacing hydronium ions with, for example, potassium ions and thus increasing the activity of the lactic acid bacteria. Further examples of the activity-increasing substances are vitamins, such as vitamin B, or growth-promoting proteins.

At least one layer of the envelope membrane is preferably constructed from at least one polymer. A polyelectrolyte complex which consists of at least one polycation and one polyanion is advantageously suitable as the polymer. Suitable polyanions are, for example, polyacrylic acid, polymethacrylic acid, polyvinylsulfonic acid, polyvinylphosphonic acid, alginic acid, cellulose derivatives, in particular carboxymethyl cellulose or cellulose-sulfuric acid esters, shellac or constituents of shellac, such as aleuritic acid or shellolic acid. Suitable polycations are, for example, polyethyleneimine, polydimethyldiallylammonium, poly-L-lysine or chitosan.

The polyanions or polycations advantageously have an average degree of polymerization of more than 100, preferably 100 to 15,000. Polymers with a narrow molecular weight distribution, for example synthetic polyelectrolyte complexes made from polyacrylic acid or polymethacrylic acid with polyethyleneimine, are preferably used for the targeted adjustment of the permeability of the envelope membrane for the permeability-determining layer (standard layer). The permeability for a small protein of the size of about 60 kD was determined through a control layer made of polyethyleneimine (PEl) (molecular weight 1,000,000) and polyacrylic acid (PAS). Table 1 shows the proportion of the protein diffused from the microcapsules as a function of the degree of polymerization of PAS after 60 hours of shaking.

Tab. 1 Permeability of the control layer for a 60 kD protein depending on the molar mass of the polyanion as sodium polyacrylate (NaPAS). As can be seen from Table 1, the permeability of the control layer is determined by the polyions, here as polyanion polyacrylic acid, which have a low degree of polymerization, while the counterions, here as polycation polyethyleneimine, form the framework with a high degree of polymerization. With the same counterion, polyelectrolyte complexes with a polyion with a high degree of polymerization have a higher strength than those with a low degree of polymerization. As counterions which form the framework to which the polyiories with a lower degree of polymerization attach, polyions with a degree of polymerization above 50,000 are preferred.

For the immobilization of enzymes, at least one control layer with a degree of polymerization of the polyanion or polycation of 100 to 1,000 is preferred, the counterions forming the framework, polycations or polyanions, having higher degrees of polymerization. In contrast, higher degrees of polymerization are sufficient to immobilize microorganisms, such as yeasts; degrees of polymerization of the polyanion or polycation of the control layer from 1,000 to 15,000 are preferred, the counterions, polycations or polyanions forming the framework also having a higher degree of polymerization here. Polyions with high degrees of polymerization have the advantage of high strength of the layer in question.

For the strength-determining layer (support layer), polyelectrolyte complexes of synthetic polycations or polyanions with high degrees of polymerization of more than 10,000 are advantageously used. Natural polycations and anions, such as alginic acid and chitosan or cellulose derivatives, in which a broad molar mass distribution does not have a disruptive effect, can also advantageously be used.

Table 2 lists examples of substances in the layers of the envelope membrane, the first line of which indicates whether this structure is preferably suitable for immobilizing yeasts and / or enzymes. For immobilization, the core can have an alginate which can be liquefied after the layers have been applied. In the columns of Tab. 2 the layer structure from inside to outside is given. With a larger number of layers, for example 4 or more layers, an even higher stability of the envelope membrane can be achieved.

Tab. 2 Examples of the layer structure of the envelope membrane in immobilized yeasts and / or enzymes (Alg = alginate, chit = chitosan, CMC = carboxymethyl cellulose, PAS = polyacrylic acid, PEl = polyethyleneimine).

In addition, natural rubber, polystyrene and / or polymethyl methacrylate or a mixture thereof with one or more polyelectrolyte complexes are also suitable as polymers for building up a layer of the envelope membrane.

The invention also relates to two uses of the agent according to the invention. So the agent can be used to produce beer. Microcapsules containing cells from one or more species of yeast used in beer production are to be used for this purpose. The agent can also be used to produce low molecular weight alcohols, such as methanol and / or ethanol, microcapsules containing yeasts suitable for producing alcohol in high yields being used.

For the production and / or treatment of, for example, wine using the agent according to the invention, the microcapsules are to be introduced into a grape, berry and / or other fruit juice, for example apple juice, or a wine. The microcapsules remain in the solution until the partial or complete conversion, for example alcoholic fermentation, has taken place. The microcapsules are then removed from the solution.

Compared to known processes in which the microorganisms or enzymes used have to be filtered off, this process has the decisive advantage that the cells or enzymes used in the production or treatment process can be removed easily, quickly and completely in the last step of the process . So that's it The residence time of the microorganisms or enzymes in the solution can be set very precisely.

Due to the size of the microcapsules, preferably diameters of half a millimeter to a few millimeters, the microcapsules can be removed easily and completely from the solution. Mechanical methods are suitable for this, for example by means of a sieve, or decanting the supernatant liquid after the microcapsules have been sedimented beforehand. With these types of removal, the microcapsules are not destroyed, so that they can be reused, if necessary, after being stored in a nutrient solution. This can reduce production costs, particularly in the case of expensive enzymes.

The solution is advantageously tempered, at least in the area of the microcapsules, in such a way that the cells or enzymes have optimal activity, taking into account any possible influence on the quality of the product.

Different microorganisms or enzymes immobilized in microcapsules can be used simultaneously or / and at different times. In the case of a staggered use, the different microcapsules can be added to the solution one after the other and removed together, or the process steps of introducing, lingering, and removing can be repeated several times with the same solution using different cells or enzymes immobilized in microcapsules. The use of different microorganisms or enzymes can thus be used to increase the complexity of a wine, for example.

A fluidized bed reactor containing the agents according to the invention can be used as the bioreactor for producing low molecular weight alcohols, in particular ethanol, or alcoholic beverages, in particular wine or sparkling wine. Suitable reactor types are also shown in Lüders, Technologie mit immobilobilen Hefen ', Brauwelt 1994, 57.

The bioreactor can also have at least one tube in which the microcapsules are contained. The two openings of the tube are advantageously closed with sieves which retain the microcapsules. This eliminates separating the microcapsules from the reacted solution. The diameter of suitable tubes is preferably in the range of one to several centimeters.

The liquid to be converted is passed through the tube, it being possible for a plurality of tubes to be connected to one another in parallel and / or in series. When simultaneous use of different microorganisms or enzymes immobilized in microcapsules, tubes of the same content are preferably connected in parallel, with groups of tubes of different content connected in parallel being connected in series. It can also be advantageous to connect individual tubes in series so that the solution flows through the tubes one after the other.

To optimize the activity of the microorganisms or enzymes used, it is advantageous to temper the inside of the tubes, that is to say the microcapsules and the solution surrounding them. For this purpose, a single tube or groups of tubes advantageously has a common temperature-controlled jacket. The activity of the cells or enzymes can be specifically reduced by cooling the microcapsules enclosed in the tubes.

In a plant for the production of low molecular weight alcohols, in particular ethanol, which contains at least one bioreactor, the liquid to be fermented, containing glucose, reaches the mixer from the storage tank. There it is mixed with the reflux from the heater and then fed into the bioreactor filled with microcapsules, where the actual conversion of carbohydrates into alcohol takes place. The alcohol is then separated in the heating vessel and in the distillation column and collected in the main product collection vessel. The alcohol is separated from the rest of the liquid using the different boiling points. After cooling in the heat exchanger, the residual liquid from the heater can be re-enriched with fresh liquid in the mixer and returned to the bioreactor. In order to avoid excessive glucose dilution of the circulating liquid, part of the aqueous portion is regularly removed and collected as a by-product in a collecting vessel. A plant for the production of alcoholic beverages has a very simplified structure. The liquid to be fermented is fed from a storage vessel into a bioreactor according to the invention, where the liquid remains or circulates through, for example, a tube reactor. The alcohol-containing product is passed out of the bioreactor into a collecting vessel after a time required for a partial or complete reaction.

Further details of the systems can be found in the following description, in which an exemplary embodiment is explained in more detail with reference to the drawing. The attached figure shows the schematic structure of a continuous plant for alcohol production. The liquid to be fermented is fed from a storage container (1) into a mixer (2), where it mixes with the liquid flowing back from the heater (4). This mixture is converted into alcohol in the bioreactor (3) by yeasts immobilized in the agent according to the invention. The alcohol-containing liquid is fed into a heater (4). An alcohol-containing gas phase is passed from it into a distillation column (5). There, the different boiling point of the alcohol compared to water is used to enrich the alcohol that is collected in the collecting vessel for the main product (6). The low-alcohol part of the pre-fermented liquid is led out of the heater, cooled in a heat exchanger (8) and returned to the mixer (2). So that the liquid in the circuit maintains a minimum content of substances to be converted, in particular glucose, part of the aqueous portion is regularly removed from the heater (4) and collected as a by-product in a collecting vessel (7).

Example for the production of microcapsules:

5 g of sodium alginate (Kelco, Hamburg) were dissolved in 700 ml of water. 70 g of dry yeast (Oenoform, Erbslöh, Geisenheim) were then stirred into this solution. This suspension was dropped into a 0.6% calcium chloride solution. After a few minutes of curing, the beads containing the yeast cells in a calcium-alginate matrix were first washed with water and then with an aqueous 0.05% solution of polyethyleneimine (average molecular weight 1 million, from Fluka) and then with an aqueous 0.06% solution of carboxymethyl cellulose (medium viscosity, from Fluka) washed. The microcapsules thus obtained were then washed with water and then introduced again into the polyethyleneimine and the carboxymethylcellulose solution. After rinsing with water, the microcapsules were stored in water. The microcapsules had a two-layer envelope membrane, each layer consisting of the polyelectrolyte complex polyethyleneimine / carboxymethyl cellulose. Because the calcium alginate beads containing the cells were first produced and the layers of the envelope membrane were subsequently applied, the layers of the envelope membrane had no yeast cells which could grow out of the microcapsules. The yeasts immobilized in this way had the same activity as yeasts immobilized in uncoated calcium alginate beads.

Claims

claims

1. means for producing and / or treating alcoholic beverages, in particular wine or sparkling wine,

consisting of microcapsules, each having at least one envelope membrane completely surrounding the interior of the capsule, the interior of the capsule comprising cells of at least one species of microorganism and / or one or more enzymes, and

wherein the envelope membrane is not permeable to the cells or enzymes enclosed in the capsule interior, and

the envelope membrane being permeable to the starting materials to be converted by the cells or enzymes and to at least some of the products converted by the cells or enzymes.

characterized,

that the envelope membrane has at least two layers arranged radially one above the other, each layer completely enclosing all layers arranged radially below it.

Agent according to claim 1, characterized in that at least two layers of the envelope membrane consist of different substances.

Agent according to claim 1 or 2, characterized in that the cells or enzymes contained in the interior of the microcapsule are embedded in a matrix.

Agent according to claim 3, characterized in that the matrix comprises an alginate compound of a polyvalent cation.

5. Composition according to claim 3 or 4, characterized in that at least one layer of the envelope membrane consists of a different from the embedding the cells or enzymes, the matrix-forming substance substance.

6. Composition according to claim 5, characterized in that the matrix in

Is liquefied inside the microcapsule.

Agent according to one of the preceding claims, characterized in that the layers are covalently and / or ionically bonded to one another.

8. Agent according to one of the preceding claims, characterized in that the envelope membrane is not permeable to active substances and / or microorganisms located outside the microcapsule, which impair the activity of the cells or enzymes contained in the capsule interior.

Agent according to one of the preceding claims, characterized in that the microcapsule contains cells of at least one species of yeast used in alcoholic fermentation, preferably in wine production.

10. Agent according to one of the preceding claims, characterized in that inside the microcapsule cells of at least one species of lactic acid bacteria used in the biological acid degradation in wine treatment are contained.

11. Agent according to one of the preceding claims, characterized in that one or more enzymes from the group of pectinases, glucanases, β-glucosidases, proteases and / or glucose-fructose isomerases are contained in the interior of the microcapsule.

12. Composition according to one of the preceding claims, characterized in that cells of at least one species of microorganisms and at least one enzyme are contained in the interior of the microcapsule.

13. Composition according to claim 12, characterized in that the microcapsule contains cells of at least one species of yeast used in wine production and at least one yeast cell wall preparation and / or a glucose-fructose isomerase.

14. Composition according to one of the preceding claims, characterized in that in addition to the cells or enzymes, at least one substance which increases the activity of the cells or enzymes is contained in the interior of the microcapsule.

15. Agent according to one of the preceding claims, characterized in that at least one layer of the envelope membrane is composed of at least one polymer.

16. Composition according to claim 15, characterized in that the polymer is a polyelectrolyte complex.

17. A composition according to claim 16, characterized in that the

Polyelectrolyte complex at least one polyanion from the group of polyacrylic acid, polymethacrylic acid, polyvinylsulfonic acid, polyvinylphosphonic acid, alginic acid, cellulose derivatives, in particular carboxymethyl cellulose or cellulose-sulfuric acid ester, shellac or constituents of shellac, such as aleuritic acid or shellolic acid, and at least one polycation from the group consisting of polyethylene dimlyl, polynlyl Chitosan or poly-L-lysine.

18. Composition according to claim 16 or 17, characterized in that the

Polyanion or the polycation has an average degree of polymerization of 100 to 15,000, the polycation or polyanion as counterion having an average degree of polymerization of over 50,000.

19. Composition according to claim 15, characterized in that the polymer is polystyrene, polymethyl methacrylate and / or natural rubber or a mixture thereof with one or more polyelectrolyte complexes.

20. Use of an agent according to any one of claims 1 to 19 for

Production of beer, characterized in that the microcapsules contain cells of one or more species of yeast used in the production of beer.

21. Use of an agent according to any one of claims 1 to 19 for the production of low molecular weight alcohols, preferably ethanol, characterized in that the microcapsules contain cells of one or more yeast species which enable the alcohol to be produced in high yields.