DE2713709A1 - METHOD FOR MANUFACTURING A PROTEIN MATERIAL WITH A TISSUE STRUCTURE - Google Patents

Description

Henkel, Kern, Feiler & Hänze! Patent attorneys

Möhlstrasse 37 General Foods Corporation D-8000 Munich

White Plains, N.Y., V.St.A. Tel .: 089 / 982085-87

Telex: 0529802 hnkld telegrams: ellipsoid

Dr.F / k

2 6. Man 1977

Process for the production of a protein material with a tissue structure

The invention relates to a method for producing a protein material with a tissue structure, in particular one fibrous protein material that is used either directly as artificial meat or for the production of artificial meat can be.

In the past few years, considerable research has gone into developing new technologies for the Production of meat-like protein foods from various vegetable and animal protein sources to develop. Economic efficiency offers a considerable incentive. It would undoubtedly be pretty beneficial uneconomical process by which animals protein

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converting containing vegetable materials into meat, at least in part through the more efficient process of growth to replace vegetable proteins. This is especially true in those areas where the world population is constantly increasing must fear that one day there will no longer be enough pasture land for meat-producing animals. There come however, even more recent efforts aimed at avoiding certain natural products that are derived from religious, appear to be undesirable for ethical or health reasons.

All natural meat, including fish and poultry, has a fibrous structure. The tissue structure of the meat products is necessarily dependent on the texture of the fibers of the flesh. In the same way, the presence of a fibrous structure is an important factor in artificially obtained meat-like products. Thus, in the manufacture of these meat-like products, e.g. of artificial meat, much effort has been made to obtain a fibrous structure similar to that of natural meat produce. Many scientists and technicians have developed a variety of techniques for achieving a fiber structure, As a result, there was a good deal about the production of artificial meat with a fibrous structure published literature there.

Thus, quite early (US Pat. No. 2,682,466), the formation of synthetic meat products with certain amounts of vegetable ones became apparent Protein fibers described. These protein fibers are produced in the known method in that a colloidal protein dispersion is forced through a porous membrane, such as a spinneret, into a coagulation bath which causes precipitation of the protein in fiber form. The fibers are then including using binders Grain and protein transformed into a meat-like product,

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The use of spun vegetable fibers enables the formation of a highly oriented fiber structure. The disadvantage, however, is that the production of spun fibers is complicated and relatively expensive. In addition, is However, spun vegetable protein is generally not very nutritious, as the starting material is obtained from substances derived from isolated soy protein.

In view of the difficulties that the technology spun As fibers are inherent in them, other scientists have been encouraged to look for alternatives to this technique. One these alternatives are described in US Pat. No. 3,488,77ο. With the help of this known method, a protein-containing Obtain a meat-like product that has an open-cell structure, the cell length being greater than the cell diameter and wherein the cells are substantially aligned. This well known product is made by extrusion a doughy filling compound, essentially free of non-proteinaceous substances, in a space of reduced pressure generated to cause expansion in this way.

Another known method which uses a dough is described in US Pat. No. 3,693,533. The the protein-containing dough coagulates as it passes through a pair of converging conveyors. The during the coagulation occurring stretching effect leads to the fact that in the known method fibers are obtained, which as one-sided can be referred to as directed.

Although these methods are less expensive than staple fiber technology, they have the disadvantage that the quality of the fibers produced is defective.

From published Japanese patent applications 48-21,5o2 and 48-34,228 and U.S. Patents 3,87o, 8o8 and 3,92o853 are processes for the production of fibrous protein masses

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known in which a protein solution or dispersion is frozen and then heating the frozen mass to hot-set the protein. These fibrous products are made described as meat-like and can be processed through a freeze-drying step can be further improved prior to heat setting.

The invention is based on the object of avoiding the disadvantages of the known methods and a new method for To create a protein material with tissue structure, which is an asset to the technology.

This object is achieved according to the invention in that

a) made a mixture of a hot-coagulable protein and water,

b) the mixture for freezing out the water in the form of elongated ice crystals and for separating the protein into well-defined, well-ordered, and substantial independent zones cooled and

c) the resulting frozen mass in an aqueous solution, which is a physiologically harmless water-soluble Contains substance that lower the freezing point of water and stabilize the protein capable of being immersed until the protein in the frozen mass is stabilized.

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In the method of the invention, an aqueous mixture of a heat-coagulable protein is used to below its freezing point cooled in such a way and at a rate that elongated ice crystals are formed, which are generally perpendicular to the cooling surface, whereupon the resulting frozen mass is converted into an aqueous Solution is introduced which contains an edible, water-soluble substance which is capable of the freezing point of the Lower the water and stabilize the protein, continuing immersion until the protein is stabilized in the frozen mass. An aqueous one is particularly advantageous in the process according to the invention Ethanol solution used.

By the method according to the invention using a A variety of protein materials a variety of meat-like tissue structures can be simulated. The common A characteristic of all these products is the presence of well-defined ones and well-ordered fibers. By the method according to the invention, the fibers are made of vegetable or protein of animal origin either produced separately or in combination. In this way it is possible at the production of a protein material with a tissue structure and with certain desirable properties the tissue, To balance the taste and nutritional properties of the fibers.

The essential points for the present invention include the need for cooling in one direction and at a rate that will guarantee that well-defined and well-ordered ice crystals will form, and the need to Stabilize the protein by immersing the frozen mass in a stabilizing solution for retention to ensure the fiber structure defined by the ice crystals.

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Any edible protein or combination of proteins can be used in the method of the present invention. provided that either the only protein or, in the case of a combination, at least one of the proteins is soluble or is partially soluble and is through the treatment according to the invention can stabilize. In general, proteins with excellent solubility properties also lead to excellent ones pronounced fibrous structures, probably because the ice crystals are unhindered by undissolved solids can grow freely. In the method according to the invention, however, protein solutions with considerable proportions can also be used of insoluble substances such as soy flour and meat and fish homogenates are used and supplied good results in the formation of fibrous structures. For example, soy milk, soy protein, whole milk, meat and fish porridge, gluten, soy flour, wheat protein concentrate, whey, eggs and blood protein, single cell protein and the like protein materials, which can be used with excellent results in the process according to the invention.

The final tissue structure of the product depends in part on the protein source used, but also in part of additives such as flavors, fillers, fat, carbohydrates, salts, etc. For example, those made from soy milk have Products a juicy, smooth and soft texture with good fiber tensile strength. Soy milk provides a product which resembles raw chicken in smoothness and softness, probably because of the oil emulsified in the protein. On the On the other hand, soy flour provides a product with a lower tensile strength than soy milk, but this type is Delicacy is desirable in some products either alone or as a component with another protein material.

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The protein, from whatever origin, is mixed with water to form an aqueous protein mixture, with at least some of the protein is dissolved in the water. The aqueous protein mixture can be used as a solution, dispersion or suspension of the Protein in water. It is possible to determine the degree of solubility of the protein that is common to the different protein types varies by adjusting the pH of the mixture to increase. To ensure optimal tensile strength and integrity to achieve the fiber, it is usually desirable to adjust the pH of the aqueous protein mixture so that that maximum protein solubility is achieved. It appears as if the pH of the mixture directly affects the Affects the tensile strength of the end product equipped with a fabric structure. Some protein materials like soy flour give a better texture and greater tensile strength at higher pH values, e.g. at pH 1o, than at lower ones pH values. The reason for this is probably to be found in the fact that these proteins become more soluble at higher pH values and are partially diassociated and denatured by the alkaline conditions before the structure is formed. at At high pH levels, the protein molecules tend to open up, allowing more complete and obvious dissociation also greater freedom of movement during the freezing process, which means more complete fiber formation favored. Some proteins, such as egg whites, have good solubility at their natural pH, which is why it doesn't it is necessary to shift their pH to alkaline ranges.

While high pH is sometimes useful in the manufacture of the fabric textured products, Excessively high pH levels in a synthetic meat product may be undesirable. The pH of the end product can be performed during rehydration, which will be described in detail later, by the use of an acid

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be reduced in the rehydration bath. Sometimes, however can reduce the pH of the product having a fabric structure below a value at which the particular Protein is immobilized, affecting the texture of the product. Depending on the end use the product is intended for is, this structural effect can be desirable or undesirable. For those proteins that are at their natural pH 6 to 8 are dissolved, no neutralization is necessary.

The water-protein mixture can easily be obtained by mixing the protein with water. If necessary, it can Protein material either before or after mixing with water can be finely divided or crushed and the pH value adjusted for optimal solubility. The presence of soluble and insoluble, non-coagulating materials can be tolerated, and in fact, in some cases, is desirable as long as they are not otherwise desirable Affected properties of the fiber structure for a particular application. In some cases it would the presence of excessive amounts of fat may be undesirable, namely where it affects the tensile properties of the fiber would degrade. In other cases, however, a reduced tensile strength is quite desirable because it affects the product gives a more delicate structure. In the process of the present invention, all those additives can be used which is normally used in the manufacture of fibrous artificial meat can be used, but it must always be kept in mind that the method of the present invention is able to modify the design features of the fiber-forming material to a large extent and in this way, starting from a single basic process, a multitude of variations in terms of tissue structure and nutritional properties to achieve. Another advantage of the present invention is that with relatively high Fat content can be worked and a good fiber structure

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is achieved.

The concentration of solids in the mixture can affect the fabric structure of the product as well as process efficiency In general, there are low solids concentrations he wishes. One reason for this is that as the solid concentration increases, there is a tendency to form a structure with separated fibers. In a typical method of the invention the solids content, calculated on a weight basis, does not exceed about 40%, preferably not about about 35%, of the mixture. With increasing solids concentration the time required for immersion in the stabilizing solution also increases. However, processing at excessively low concentrations is because of the increasing costs for the removal of the water uneconomical. With decreased concentration, the cost of energy, containers, and transportation and storage equipment increases quickly. On the other hand, however, the quality of the fibers produced at low concentrations is very high Well. It is therefore necessary to determine the optimal concentration for each system separately, always taking into account the fact that a large number of influencing factors must be taken into account. In a very wide way Meaning that the optimal concentration in the freezing process for the protein is somewhere between 3% and 35% based on the total weight of the water-protein mixture, concentrations between 1o% and 3o% being preferred are. It is obvious, however, that the optima for particular proteins and adjunct materials within this Range very strongly and can sometimes also extend beyond this range.

In particular, knowing the profitability of the With the equipment and procedures available, any person of ordinary skill in the art is readily able to make these optima

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for the particular systems he uses. In addition, the examples given below provide will give those of ordinary skill in the art working examples for a number of different systems.

For example, every concentration that allows it is essentially independent of one another, oriented in its direction To produce fibers suitable for the method of the present invention. In each individual case the specific one must be Concentration must be determined for the desired and acceptable balance between the physical properties of the product and the effectiveness of the process.

It must be noted, however, that a gel-like protein material about the kind used in the production of tofu (soy quark), where the gel structure absorbs the water prevents the formation of long crystals, can not be used for the method according to the invention.

Once made, the aqueous protein mixture is made accordingly a pattern defined in terms of its direction cooled below its freezing point, thus due to the Formation of ice crystals creates a well-defined, well-ordered fibrous structure. At the moment when that If water is frozen to ice, the concentration of the remaining protein mixture increases · Due to the formation of ice crystals the protein material is divided into separate, generally parallel-aligned zones. Included any means which allow this result to be completed is suitable according to the present invention. The ice crystals form a latticework, between whose elongated ice crystals the protein is arranged in fiber-like structures Shares is included. The zones where the protein material is located are almost completely separated from one another and during coagulation essentially form

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other independent protein fibers. However, the protein zones are not completely independent of one another, but rather rather, they are connected to one another at a sufficient number of points so that the individual zones form a branched one or networked structure are summarized. The degree of linkage achieved should just be sufficient to produce the end product to impart a cohesion similar to cooked meat, and is not intended to cause a destruction of the substantially one another lead independent fibers. This link, which is achieved during the formation of the fibers, makes the No need to add binding agents.

The freezing out is accomplished in that at least one surface, preferably one surface, or two each other opposite surfaces of the mixture are cooled below their freezing point. The cooling should preferably be carried out in such a way that that the freezing process propagates through the entire thickness of the mass and is generally parallel to the formation Leads fibers that are generally perpendicular to the cooling surfaces.

The cooling surface or the cooling surfaces are preferably flat. However, you can also use any other regular or irregular Own configuration. For example, a single cooling surface can be used that is in contact with the aqueous Protein mixture has a hemispherical or spherical or cylindrical design. In these exemplary The ice crystals that form and thus also the protein fibers would fall essentially perpendicular to the Tangents of this surface stand and generally extend towards the center. Forms during the freezing process An interface develops between the frozen mixture and the still liquid mixture, which continues to move in the cooling direction. This interface corresponds to the typical freezing temperatures used in accordance with the invention

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generally the shape of the chilled surface of the protein mixture, provided the chilled surface is not highly irregular. Under other conditions, however, this interface can also assume a somewhat modified shape in accordance with the present invention. The process is to be understood in such a way that as soon as part of the mixture has started to freeze through, the advancing freezing limit becomes the cooling surface through which the heat transfer takes place. It is this moving interface that is responsible for the formation of the pattern of the formation of the ice crystals and thus the fibers . The main considerations in all of these cases must be to produce well-defined fibers that have an orderly orientation similar to natural meat. If necessary, those areas of the mass which are not in contact with the cooling source can be insulated in order to reduce the heat transfer through these areas. In most cases it has been observed that those surfaces which are not in contact with one or two opposing cooling surfaces have randomly oriented fibers to a certain thickness. The reason for this is that directional cooling in these corners is difficult to achieve due to the incidence of heat from the outside. These corner parts can either remain in the end product or can be separated by cutting with a knife, a heated wire or the like. It must also be noted that when two opposing surfaces are cooled, horizontal discontinuity surfaces appear, by means of which the frozen mass is divided into two parts. Obviously, this is due to the independent crystal growth proceeding from each of the opposing faces in the direction of a contact plane in the center of the mass.

Numerous cold sources can be used in accordance with the invention . For example, the aqueous protein mixture can simply be put in a pan and the pan on a piece of dry-

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put ice cream or slightly (e.g. 0.32 cm) in a cold one Liquid such as liquid nitrogen, ethylene glycol, cooling brine or the like can be immersed. Alternatively, a container placed with the aqueous protein material on a plate freezer or one between two freezing plates Plate freezer can be arranged. A treadmill freezer such as that described in US Pat. No. 3,253,42ο would also be suitable and 3,6o6,763.

The temperature used can be any which causes them to become substantially independent of one another directionally Form ice crystals. The cooling rate is generally not a factor that affects the formation of well-defined, well-ordered and elongated fibers, as long as the cooling takes place essentially in one direction, however, the rate of cooling has a decisive influence on the size and shape of the crystals. A quick cooling leads to form small microscopic ice crystals. With a Slower cooling or freezing speeds produce long, needle-shaped ice crystals. The preferred Cooling rates, defined as the rate of migration of the freezing interface, range from about 0.61 to about 3o.48 cm / h, preferably from about 0.91 to about 15.24 cm / h (about 0.02 to 1.0 ft / h or 0.03 to 0.5 ft / h). At the moment it appears as if the temperature of the protein solution or protein sludge before the freezing step In no way critical, but it is believed beneficial, is the temperature of the solution or sludge get as close to freezing as possible before freezing. At the moment, this is just for reasons preferred to economy. It is known that it is less expensive in terms of refrigeration technology to use a liquid with conventional Means to cool if it can be stirred and an intimate contact with the heat-extracting media takes place as if the cooling or freezing with the help of a single or two opposing heat exchange elements

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ments is made. However, precautions must be taken be that the liquid mixture is not supercooled before the freezing process, as this becomes too rapid an arbitrary Leads to cooling, which results in an undesirable random fiber structure in the product.

After freezing, if desired, the crystal structure Easily observe the material by breaking the frozen mass and looking at it visually.

So that the individual protein fibers formed in this way remain intact, the protein is made according to the present Invention stabilized by immersing the frozen mass in an aqueous solution that is edible, water-soluble Contains substance that on the one hand lowers the freezing point of water and on the other hand stabilizes the protein. If the substantially soluble protein is not stabilized prior to heating such as heat setting, the heating leads to an excessive binding of the individual strands, since the ice crystal lattice separating them melts. if the fibers are then heat set, then they tend to form a less pronounced fibrous mass. For For many types of artificial meat, especially for artificial fish, this excessive binding of the protein material is undesirable. For the same reason, the frozen mass should not be stored for long periods at temperatures which are only slightly below the freezing point of the mass. Storage under these conditions leads to recrystallization of the ice and a disorientation of the fiber structure. While this can to some extent be considered a means to influence the tissue structure of the artificial meat product be desirable, only it must be done with the awareness that a reorientation is taking place, and it can only be up to to such an extent as is desirable for a particular application.

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The immersion of the frozen mass in the stabilizing solution can be carried out in any suitable manner using conventional Means to be accomplished. The product can be crushed either before or after immersion.

Water-miscible organic solvents are known for the precipitation of proteins. Any of these known substances can as a stabilizing agent in aqueous solution in the process according to of the invention, provided it reduces the amount of water available to the protein as well like the hydrophilic potential of the protein due to conformational changes in the protein and the freezing point and surface tension of the water. The amount of water available for protein is reduced quite simply by that the mole fraction of the water is reduced in the presence of these stabilizing substances. That way stands less water is available to dissolve the protein. Effective stabilizing agents also cause a shift of equilibria

hydrated, random protein ball

- Helix + water

- conformation + water

to the right, which affects the solubility of the protein in the opposite direction. The most effective stabilizers, which can be used reduce the surface tension of the water and thus at the same time the contribution of the water for adhesion to the hydrophobic groups of the protein. As could be established, show in the case of organic solvents those molecules that contain short, straight-chain hydrophobic groups have the most remarkable adhesion and thus a reduction in protein solubility. The lowering of the freezing point of the water is essential, as the stabilizing agent must be able to do so, the ice to penetrate in the frozen product mass.

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Suitable stabilizers are polar organic solvents such as alcohols, with ethanol because of its non-toxicity, even if relatively large residual amounts of this solvent remain in the product is preferred. Despite this particular preference for ethanol, the method of In the invention, any solvent can be used as long as it has the above-mentioned functions and at the concentrations after removal of the solvent in any known manner, such as extraction and drying, remain in the product, is non-toxic. The known acids are also used as stabilizing or coagulating substances and salts are suitable which have the functions necessary in the present case in aqueous solution. If desired, these known salts and / or acids can be used in combination with an alcohol, such as ethanol, or other organic solvents be used. Such combinations have the advantage that they are with regard to a specific process or a mutual weighing of the advantages and characteristics of the various stabilizing agents for a specific product application allow.

The acids suitable for the process according to the invention include hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid and other physiologically harmless acids. To the for that Salts suitable for processes according to the invention include the physiological ones harmless ammonium, alkali and alkaline earth salts of these acids, as well as other salts, the above mentioned Own functions.

The ethanol is only one example of numerous suitable stabilizing materials for the process according to the invention, however, for the sake of conciseness, it is used as a stabilizing agent in the following remarks.

When a frozen mass of protein and ice prepared in the manner described above is placed in a coagulating bath with

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Ethanol is brought into contact between the two phases, namely the water in the protein and in the ice crystals on the one hand and the ethanol on the other hand, a diffusion exchange takes place. The ice crystals melt and the protein phase becomes less watery with penetrating alcohol. As soon as the protein comes into contact with the alcohol, it turns into a insoluble form and the fibers are stabilized. For complete conversion into the insoluble form, the Alcohol completely penetrate the protein phase. After a sufficient period of time, no more exchanges take place, i.e. a state of equilibrium is reached between the two phases. The final equilibrium concentration of alcohol in the coagulating bath depends on the alcohol-water ratio of the frozen protein mass. The concentration of the Alcohol in this coagulating bath affects the freezing point of the solution as well as the diffusion and coagulation speed of the protein, all important regulating factors in the invention Procedure.

When the unidirectional frozen protein mass is placed in the alcohol bath in order to avoid the due to the To stabilize the fiber structure aligned in the frozen state, the temperature of the bath must be lower than the freezing point of the protein solution. This immobilizes the free water and thus rehydrates it of the protein and a dissolution of the structure aligned by the frozen state by the water prevented. At freezing temperature, water exists in the form of ice crystals in the protein mass. When the ice crystals with When alcohol comes in contact, they melt, and water diffuses out. At the same time, the protein comes along a sufficient concentration of alcohol in contact and is thus converted into an insoluble form. If the temperature of the alcohol bath is close to the freezing point of the water, for example higher than -5 C, then takes place in

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the frozen protein block undergoes recrystallization, with the effect that the The fiber structure disappears and gives way to a random structure.

The degree of freezing point depression depends on the concentration of the solvent added to the solution. As a result the freezing point of the coagulating bath can be regulated by changing the alcohol concentration. So that a freeze the alcohol bath is prevented, the freezing point of the coagulating solution must be below the process temperature.

Although it can be any concentration effective for the intended purpose of stabilizing agents can be used, however, if ethanol is used, the concentration should be approximately above 10%, preferably above 2o%, are kept. In an experiment with 5% ethanol, the protein was completely converted into its soluble form and the fiber structure destroyed. In another one with 10% ethanol, the protein was partially converted into its soluble form. The fibers were very soft but did not fall apart. With 20% alcohol the protein was not soluble in it Form transferred. However, the texture was soft due to partial hydration. With an alcohol concentration above In 30% the protein was completely insoluble and the texture of the fiber material was hard and exceeded the equilibrium concentration of the alcohol in the coagulation process was 70%, then the fibers were due to excessive dehydration of the protein very fragile. Accordingly, it appears that the optimum equilibrium concentration is around 60% ethanol lies.

During this process, the ethanol-soluble pigments, carbohydrates, oil and fat contained in the protein diffuse out. From the standpoint of removing pigments and undesirable substances from the products, this is also quite desirable-

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value. Fat and oil can be recovered and found in food be used.

As soon as the fiber mass is stabilized in this way, it can be dried, stored indefinitely or immediately heat set and then stored for further uses. At the moment, however, it is with the method according to the invention prefers to heat set the fibers prior to rehydration. The heat setting strengthens the protein fibers. If heat setting is not performed prior to rehydration, then the desired structural properties can deteriorate.

With a suitable choice of heat treatment it is possible to change the fabric structure, the color, the toughness, the tensile strength and affect the rehydration and water retention properties of the final product. Fabric-structured materials, those exposed to intensive heat treatment tend to use less water when rehydrated to record. However, all materials provided with a fabric structure and manufactured according to the invention are obtained preferably a heat treatment sufficient to increase the structural integrity of the fibers. So For example, mild heat treatment has been found to be extremely effective on the final product gives an extremely good meat-like texture.

The effort made to stabilize the product during the heat treatment, be it with or without pressure, depends on the The type of protein material used. For example, dry soymilk fibers are used to stabilize their structure preferably heated in an autoclave under a pressure of 2.047 bar (15 psig) for about 5 to 10 minutes while for example Soy flour fibers on the other hand under the same

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Conditions are heated for about 20 to 25 minutes. According to the invention, any combination of time, temperature and applying pressure if only capable of heat setting the protein in the form of substantially independent fibers. As could be determined, a heat treatment in the temperature range from about 100 ° C to about 120 ° C is for about 5 to about 30 minutes, depending on the fabric structure desired in the final product, is generally adequate. The exact The average person skilled in the art can easily determine times, temperatures and pressures for a large number of products. As a guide, may use the specific heat treatment procedures given in the examples below to serve.

Typical heating devices for the method according to the invention Can be used are conventional autoclaves or steam chambers, in which pressures up to 2,391 bar (20 psig) and Allow temperatures to reach up to about 130 ° C. Electrically heated or gas-fired ones are also suitable Infrared ovens in which high relative humidities can be maintained. The use of a damp heat in such facilities or in the aforementioned autoclaves or steam chambers is a valuable aid for a more complete coagulation or immobilization of the protein material. The type of specific used On the other hand, heating means are not critical to the present invention. When using the heating devices it is only necessary that there is the possibility of a sufficient heat in terms of duration and intensity which coagulates and immobilizes the protein, so that loss of protein fibers during rehydration be prevented as much as possible.

After heat setting, the fiber-like protein material either to be placed on the market as it is, or

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it can also be rehydrated immediately to create a more meat-like texture. The rehydration leaves extremely easy to accomplish by soaking the product in water until the desired Water content is reached. The rehydration solution can contain acids to neutralize residual alkalis, flavors, emulsified fats, flavor enhancers, spices, sugar, hot-coagulable or soluble proteins, amino acids and the like. contain. In this way the product can be modified so that it not only changes the tissue structure of the meat as well whose taste is preserved. Of course, as already explained above, these ingredients can already be added to the aqueous protein mixture be added before the freezing process. From experience with certain recipes, the specialist learns which one These additives must be added in place of the process.

The invention will also be described with the aid of a few exemplary embodiments, but these are in no way restrictive of the invention are to be understood. Unless otherwise highlighted, all information, including percentages, relate to on a weight basis.

Example I.

To make a textured soy protein product with highly oriented, well-defined fibers, is called Soy milk used as a source of protein. To make the soy milk, 600 g of soybeans are soaked in water overnight, that is changed several times. The soaked beans are then hot-ground with boiling water, with the Ratio of water to soybeans is about 1o: 1. The resulting sludge is heated to a boil there for about Hold for 15 min and then filtered through a double layer of a sieve cloth. The rest on the sieve will discarded and the level of solids in the remaining

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existing liquid determined. The pH of the supernatant liquid is then adjusted to 7.5 using 2N NaOH. In addition, an antioxidant is added to the supernatant liquid at a level that corresponds to 0.02% of the fat content. Since full fat soybeans were used, the fat content of the supernatant liquid is approximately 1/4 the weight of the solids present. The soy milk is then poured into an aluminum pan to a height of approximately one inch. The pan is then placed on a block of dry ice (-76 ⁰ C), which extends over the entire bottom surface of the pan. Ice crystals soon form which are aligned in one direction, namely essentially perpendicular to the bottom of the pan. After about 30 minutes the mass is completely frozen. It is removed from the pan, placed in 95% ethanol at -5 ° C to -1o ° C, in a ratio of 1: 4, and then stirred for 8 hours. The stabilized fiber material is then squeezed out perpendicularly to the direction of the fibers by applying pressure in order to accelerate the release of ethyl alcohol located in the spaces between the fibers. The pressed product is then air-dried to remove water and residual alcohol. This drying process strengthens the structure. To further strengthen the structure, the dried material is then treated in an autoclave for 10 minutes at 2.047 bar. The heat set material is then rehydrated by soaking in water for about 20 minutes and provides a product with discrete, long, soft and easily chewable fibers.

Example II

This example is similar to those of Example I in all other respects, only the pan containing the soybean milk is held on dry ice in a freezing bath of propylene glycol (-32 ⁰ C) o to a depth of about immersed 32 cm.

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Example III

In this example the procedure is carried out exactly as in example TI, only this time the stabilized one is used Fiber material not pressed out, but instead placed in a vacuum chamber for 15 min to remove residual alcohol.

Example IV

A fibrous soy protein product is made from isolated soy protein manufactured. 100 g of isolated soy protein (91% protein) are mixed with 900 g of water to form a 10% solution, whose pH value is set to 7, ο to 8, ο. These Solution is poured into a pan to a height of approximately one inch and frozen as described in Example III and stabilized.

Example V

Isolated peanut protein becomes a fibrous peanut protein product manufactured. 150 g of isolated peanut protein (93% protein) are mixed with 85o g of water to form a 15% solution added, their pH value adjusted to 7, ο to 8, ο will. This solution is poured into a pan to a height of approximately one inch and frozen as in Example III and stabilized.

Example VI

A fibrous egg albumin product is made from fresh egg white. The protein of several eggs is separated from the yolk, put in a pan and frozen and stabilized as described in Example III. With particular advantage in this

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Example also a 10% egg albumin solution made from protein powder be used.

Example VII

A fibrous fish protein product is made from a 15% mixture of fresh fish meat in water. To the Preparation of this aqueous mixture is 150 g of lean fish meat with 85o ml of cold 3% NaCl solution in one Waring Blendor (Trade Mark) homogenized at high speed for about 5 minutes under vacuum. The resulting homogeneous mixture is then placed in a pan and frozen and stabilized as in Example III.

Example VIII

A fibrous milk protein product is made from fresh whole milk. The milk is put in a pan, frozen and stabilized as in Example III.

Example IX

This example is a repetition of example I, but the soy milk is concentrated as follows: The pH value the soy milk is adjusted to 4.5 by adding 1N HCl. The resulting precipitate is separated off by centrifugation at 500 G for 20 minutes. The protruding Liquid is discarded. The precipitate is transferred to a mixer and water is added there, and the mixture is kept for 20 minutes mixed. In this way you get a smooth and concentrated Soy milk with 18 to 20% solids. Using 2N NaOH, the pH of the soymilk sludge is increased set about 7.5 and then put the sludge in a pan and, as in Example I, frozen and processed.

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'tr

In addition to the examples given above, however, numerous modifications are still possible for the average person skilled in the art Variations are conceivable, all of which are within the scope of the invention.

- patent claims -

709843/0653

Claims (9)

Claims ^r 1l method for producing a protein material with a tissue structure, characterized in that a) made a mixture of a hot-coagulable protein and water, b) the mixture for freezing out the water in the form of elongated ice crystals and for separating the protein and cooled into well-defined, well-ordered and essentially independent zones c) the resulting frozen mass in an aqueous solution, which is a physiologically harmless, water-soluble Contains substance that can lower the freezing point of water and stabilize the protein, so is immersed for a long time until the protein in the frozen mass is stabilized. 709843/0653 ORIQINAL INSPECTED 2. The method according to claim 1, characterized in that that the resulting stabilized material is heated to coagulate the protein. 3. The method according to claim 2, characterized in that that the stabilized protein is dried before heating. 4. The method according to any one of claims 1 to 3, d a characterized in that the physiologically harmless substance that lower the freezing point of water and increase protein able to stabilize, contains ethanol. 5. The method according to claim 4, characterized in that the concentration of the ethanol greater in the aqueous solution, based on the weight of the solution, prior to immersion of the frozen mass than 20%. 6. The method according to any one of claims 1 to 5, characterized in that the The pH of the protein-water mixture is adjusted to increase the solubility of the protein. 7. The method according to claim 4 or 5, characterized in that the stabilized protein is treated to remove residual ethanol. 8. The method according to claim 7, characterized in that the residual ethanol is removed by placing the stabilized protein in a vacuum. 7098A3 / 065 3 9. The method according to any one of claims 1 to 8, since - characterized by that the temperature of the aqueous solution of step (c)
is kept below about -5 ° C during immersion . 709843/0653