DE2608084A1 - METHOD OF MANUFACTURING A TEXTURED FOOD PRODUCT - Google Patents

Description

"ATS?" LAWYERS

DR. E. WIEGAND DIPL-ING. W. BEMANN 2608084

DR. M. KÖHLER DIPL-ING. C. GERNHARDT

MÖNCHEN HAMBURG TELEPHONE: 555476 SOOO POSSIBLE 2, TELEGRAMS: KARPATENT MATH1LDENSTRASSE 12 TELEX: 529068 KARPD

February 27, 1976

W. 42 49o / 76 7 / HS

Unilever Έ.Υ.
Rotterdam (Netherlands)

Process for the production of a textured food egg product

The invention relates to a process for the production of edible textured or structured protein-containing products, be: which one is a protein solution brings this material into contact with a cooling medium in separate crystal layers of solvent, which are kept at a distance by crystalline, shaped intermediate layers of protein, controllable freezing, ensuring that all of these layers are in a common, generally perpendicular direction extend to the cooling surface, and stabilize the developed structure to obtain a textured product.

US Pat. No. 3,380,808 describes a process in which an aqueous slurry,

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ORIGINAL INSPECTED

exposing a puree or a fraction of protein-containing material to a cooling medium, controllably freezing the aqueous sludge in bis-crystal layers spaced apart by crystalline-shaped protein sludge particles, and irreversibly solidifying or hardening the crystalline-shaped protein layers into a structured product. The solids content of the slurry is at least 15 ° ₅ and the protein is predominantly present in an undissolved state.

The above method has certain drawbacks, especially in the pail when meat is used as the starting material for structural development. When the meat does not contain very little connective tissue or fat, the products obtained both show insufficient structural alignments in the frozen state as well as after cooking. Cooked products have a fairly dry and crumbly appearance Structure.

It has been found that the above and other disadvantages associated with the above process can be avoided to a great extent if, instead of using a meat puree, a vegetable protein broth or sludge as in the prior art is described, a protein solution is subjected to freeze texturing or structuring.

According to the invention, protein solutions are used in which the protein present is predominantly present in a dissolved state _{or the like}

Under "predominantly in the dissolved state" is used in this Context understood that more than $ 50 des. "-" oteins in

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the supernatant phase after centrifugation for 60 min remain at 4o,000 χ g.

Usable solutions of proteins to be subjected to G-freeze texturing contain 3 to 3o G-ew.yb protein. The use of proteins derived from different supply materials can be considered. If solutions of myofibrillar proteins, such as meat or fish proteins, are used, concentrations of 3 to 10 $, preferably 6 to 10 $, of proteins are suitable and give satisfactory products. If solutions of globular or spherical proteins, such as proteins isolated from oil-bearing seeds, are used, concentrations between Io and 3ofi> are preferably used. The solvent is preferably water or an aqueous salt solution.

The preparation of solutions of high-functional proteins which are to be used in the Y. ^r iederstrukturierung from a protein-containing food, comprising a protein extraction from the delivery material, and a concentration of this lösliehen extract to a suitable height for structural development.

The protein extraction from the delivery material can be carried out by using an aqueous solution of a Alkalis used under very mild conditions to minimize any denaturation of the protein. The alkali solution should be relatively dilute, e.g., with a molarity in the range from 0.025 to 0.21J, preferably about o, o5 to ο, ΙΙΙ. The temperature of the mixture during the extraction and all subsequent processing steps should preferably be kept at about 20 ° C or lower will. The duration of the extraction should also be

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2808084

nimum be kept ₅ -las siit achieve appropriate yield of extracted material compatible is Sine extraction time in the range of from 3o to 60 min is preferred. The alkali used is preferably sodium hydroxide, but other common alkali such as potassium hydroxide, sodium carbonate, potassium carbonate and ammonium carbonate can be used if desired.

When an alkali solution is used as an extraction solution the pH of the protein solution should be adjusted by using a dilute aqueous acid such as hydrochloric acid, sulfuric acid, Phosphoric acid or acetic acid, reduced; v / earth. The pH value is preferably set to a value between 5, o and brought 8.5.

It can also be another aqueous solution of a protein-dissolving Agent made from urea or guanidine hydrochloride or other related urea compounds in a high concentration is used. A very useful aqueous extraction solution for meat, which is preferably used according to the invention is a solution of an alkali salt such as sodium chloride or potassium iodide. Such salts can be used in a concentration of up to 1M and preferably in a concentration of about 0.6M pH between 7 and 9 in the presence of a phosphate buffer.

The concentration of the solution which has been brought to the desired pH value can be obtained, for example, by any conventional ultrafiltration apparatus used, but a tubular module design) is preferred. The ultrafiltration leads to the removal of undesired constituents of the filtrate, such as colored materials, saponified fats and salts, and also concentrated the filtrate to produce a solution of increased pro-

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to create teether.

The Gefriertexturierung of the protein solutions according to the invention is preferably added after venting of the protein solution and adjusting the pH to the desired value ^ 7erts (for muscle proteins, a pH ^»r ert 5.7 to 7.5 recommended) executed. Refrigeration temperatures between -3o ° 0 and -8o ° C are commonly used. Controlled freeze texturing can be performed in a number of ways. One of the suitable methods includes unidirectional freezing, which means freezing in such a way that the formation of solvent crystals occurs in one direction. In this method, a partially insulated container is used, one of the surfaces of the container being brought into contact with a cooling medium. This process is explained in more detail in the examples.

Another method according to the invention is that the protein is subjected to centrifugal freezing. "Centrifugal freezing" is understood to mean an operation in which the liquid to be frozen is placed in a centrifuge is brought, which is then rotated at high speed and at the same time subjected to a reduced pressure will. The reduced pressure causes solvent evaporation from the surface of the liquid and subsequently a directed freezing of the!, let the liquid come ο

A stabilization of the developed in frozen protein solutions according to the invention may sometimes structure / ärmeverfestigung by direct V or heat curing of the frozen protein solution between 8o and 125 ⁰ C, preferably in

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a humid atmosphere.

It has been found that a particularly advantageous way of stabilizing those in a frozen protein solution developed structure includes freeze-drying.

Freeze drying has been found to be a very suitable method, especially when using proteins apply that during the heat-setting treatment of the Frozen solutions would easily dissolve again, causing some of the developed structure to disappear would be initiated.

A method which is preferably used when a solution containing, for example, soy proteins is to be freeze-textured, comprises a centrifugal freeze-drying process which simultaneously effects the development of structure in the solution and the stabilization of the organized structure. The freeze-dried materials are usually further stabilized by heating in a humid atmosphere between 50 ° and 125 ° C. Another very useful stabilization method involves adding a crosslinking agent to the protein solution prior to freeze texturing. Crosslinking agents limit protein / water interactions during thawing, which occurs when a frozen protein solution is thermally solidified. Introduction of bifunctional bridging reagents restricts the free migration of protein molecules. Various crosslinking agents known in the art, such as alginic acid dialdehyde or starch dialdehyde , can be used. Starch dialdehyde is preferably used.

The concentration of the reagents and the pH of the solution require careful control so that

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it is ensured that the ice crystal organization is largely completed before the crosslinking reaction takes place. The formation of ice crystals itself provides such a level of concentration that protein and crosslinking agent are brought into more intimate contact in the areas where the reaction is required. If starch dialdehyde is used, it is recommended to use this reagent in a concentration between 0.5 and 10 $, preferably 0.6 to 1.5 $, based on the weight of the protein present. The pH of the solution containing starch dialdehyde and protein is brought to a value between 5.7 and 12, preferably between 6 and 9>. If further stabilization is necessary, this may be effected by heat denaturation of the frozen solution at a temperature from 80 to 125 ⁰ C.

The above-described method of restructuring proteins offers many advantages that are unparalleled with the The use of protein solutions is different from the use of protein slurries. Among the many Advantages are to be mentioned:

(a) the possibility of an intimate molecular mixture of proteins from different sources in order to be beneficial End product properties and ability the creation of a close mix,

(b) the possibility of obtaining functional proteins in an economical manner and in particular from e.g. Meat or fish residues,

(c) the dispensability of a complex maceration system, since the protein solution is already homogeneous,

(d) the ease of venting the proteinaceous material prior to freeze texturing due to the

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Essence of dense protein particles that hinder the movement of air bubbles,

(e) the ease of pumping protein solutions, which tend to be less viscous than their sludge equivalents,

(f) the greater mobility and effectiveness of the freezer * Process due to the lower viscosity of a protein solution,

(g) the achievement of a better control of the structural appearance by changing the protein or salt concentration, and

(h) better organization and full evaluation of protein functionality due to the fact that each Protein molecule can migrate freely evenly.

The products obtained according to the method according to the invention were tested by subjecting them to texturing measurements which led to the conclusion that the products according to the invention have better alignment, or in other '. "places, they show a superior anisotropy and a greater resemblance to natural meat as compared to the prior art products. V / enn the products according to the invention were subjected to taste tests, it was found that they were a compliant and have a juicy texture when chewing. The appearance of the products was very similar to that of first class Meat or fisoh.

The invention is explained in more detail below with the aid of examples.

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example 1

5 kg of pre-minced low quality beef was prepared using 50 kg of a 17 50 g solution Sodium chloride and 24-0 g sodium phosphate with a pH value extracted from 7jO. The temperature was during the extraction between 5 and lo ° C. Collagen material was filtered out and additional insoluble material was passed through Centrifugation removed. The clear solution was concentrated on a tubular module ultrafiltration system at 20 ° C. That Concentrate contained about 3.7 ^ protein, of which about 7o? S in dissolved state. This concentrate was deaerated by centrifugation and the pH fourth of the concentrate was brought to about 6, ο. The concentrate was in cylindrical A cry Ig las for me η (Poryruethacrylatformen) with vertical walls of 7 mn thick cast to a reasonable Isolation and rapid, adjustable, directional freezing on a horizontal bed of solid • Get carbon dioxide at about -80 ° C below, and then freeze-dried. After the freeze drying step was completed, the samples were placed on a preheated Rapidaire steam oven transferred and kept at 100 ° C in order to solidify the protein by heat or to harden it by heat. The product was finally fully rehydrated in cold solution water

Example 2

7.5 kg of ground low quality beef was mixed with 40 kg of tap water using a Silverson mixer mixed. 3s thereupon became dense collagen material filtered out. 1.75 kg of sodium chloride in Io kg Tap water was then added and the pH was raised using a 40% sodium hydroxide solution 12.5 brought. After 5 minutes, the extract was washed with 4n-

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- Io -

Hydrochloric acid to a pH of 7, ο neutralized. Insoluble U ^ terial was made by filtering and then by Centrifugation removed. The clear solution was concentrated by ultrafiltration as described in Example 1. It a protein concentrate was obtained which had a protein concentration of 5.55 », of which $ 99 was in the dissolved state templates. This concentrate was treated further as described in Example 1.

Example 3

15 kg of crushed cod waste was added to 100 kg of an o ^ M-ffatriuinchloriälösung and using a Silverson-IIischers mixed. The insoluble material became as described in Example 1, removed. The clear solution was subjected to ultrafiltration under the same conditions as described in Example 1 subjected. This concentrate was deaerated by centrifugation and the pH was raised to 6.5 brought. The concentrate contained about 3.8% protein, of which more than $ 5o were present in a dissolved state.

The concentrate was frozen in a controllable manner under the conditions described in Example 1.

Example4

20 kg of cod waste were mixed with 200 kg of frozen o, HT sodium hydroxide using a Silverston Miser extracted. The mixture was then neutralized to a pH of 7.0 with 4N hydrochloric acid. 1.45 kg of ITaCl were then added to the solution and dissolved. The insoluble material was removed as described in Example 1. The clear solution was then concentrated by ultrafiltration.

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centered. The pH was adjusted to 6.5 and the concentrate containing about 3) 4% protein of which more than $ 5o was present in a dissolved state a freeze texturing as described in Example 1, subjected.

Example 5

5 kg of soy flakes were mixed with 50 kg of cold tap water and centrifuged to remove insoluble material, Sodium chloride was added to the mixture to obtain a 4% saline solution. The pH was adjusted with sodium hydroxide set to 7 »5. The solution was adjusted to a protein content of $ 14.2, of which more than $ 50 was in a dissolved state. As in Example 1 described, controllably frozen and freeze-dried.

The freeze-dried material was heat solidified ^{in a humid atmosphere at 115 ° G.} The product was completely rehydrated in cold water or in a saline solution.

Example 6

The procedure of Example 5 was followed with the Exception that the concentrate is centrifugal freeze-drying was subjected.

Example 7

The procedure for extracting soy protein according to Example 5 was followed. The insoluble material was removed and the pH of the solution was brought to 6.5. The solution was concentrated to make a concentrate of about $ 14 To get protein. 1% by weight of Dialde-

hydric starch based on the weight of the protein was added. The mixture was, ".vie in .Example 1 described, adjustable frozen and then heated at 115 ⁰ G in a humid atmosphere, the dried product was rehydrated in cold water. _O

Example 8

1 tolumen of meat protein extract obtained according to the method of Example 1 and 3 volumes of soy protein extract obtained according to the method of Example 5 were mixed and then concentrated by ultrafiltration, to make a concentrate containing about 13 $ protein, of which at least 9ofs in solved state existed. The pE ^T "7ert was about 6.5. The mixture was controllably frozen, heat set and rehydrated according to the procedure of Example 1.

Example 9

1 volume of fish protein extract obtained by the method of Example 4 was mixed with 3 volumes of soy protein extract obtained by the method of Example 5. The mixture was concentrated to give a joint concentrate of $ 16 protein, about $ 70 of which was in a dissolved state. The pH was adjusted to about 6.5. As described in Example 1, the protein concentrate was frozen ^{in a controllable manner, freeze-dried on it and heat-solidified at 115 °} C. in a moist atmosphere.

Claims (18)

2608034 claims 1. Process for the production of a textured food product, characterized in that a protein solution in which the protein is predominantly dissolved State is present in crystal layers of solvent, which are kept at a distance by crystalline-shaped intermediate layers of protein, which are in a Extend direction, which is usually perpendicular to a cooling surface, controllable freezing by at least brings part of the surface area of the proteinaceous material into contact with the cooling surface and the developed Structure stabilized. 2. The method according to claim 1, characterized in that that an aqueous solution of protein is used in which more than 50 $ of the protein is present in a dissolved state are. 3. The method according to claim 2, characterized in ο to Ii
are in hand. 7o that upstream in a dissolved state until loo i ° of the protein 4. The method according to any one of claims 1 to 3 »thereby characterized in that the total protein content is at least 3% by weight. 5. The method according to claim 4, characterized in that the total protein content is Io to 3o Gfw. $ £. 6. The method according to any one of claims 1 to 5, characterized in that a solution of proteins of different Origin is used. 609837/0753 7. Procedure according to. Claim 6, characterized in that because a solution containing fish protein and soy protein is used. 8. The method according to claim 6, characterized in that a solution containing meat protein and soy protein, is used. 9. The method according to claim 1, characterized in that the developed structure by thermosetting the frozen Solution is stabilized between 8o and 125 ° C. 10. The method according to any one of claims 1 to 9 »characterized in that a solution of muscle fiber proteins with a pH value of 5.7 to 6.5 can be regulated frozen and then between 8o and 125 ⁰ C is thermally solidified. 11. The method according to any one of claims 1 to Io, characterized characterized in that the developed structure is stabilized by freeze drying the frozen solution. 12. The method according to claim 1, characterized in that the development of the structure in the protein solution and the Stabilization of the structure obtained can be carried out in a process in which the protein solution is centrifugal freeze-drying is subjected. 13. The method according to claim 12, characterized in that the freeze-dried material is further ^{stabilized by heat consolidation between 8o and 125 0} C in a moist atmosphere. 14. The method according to claim 1, characterized in that the protein solution is a crosslinking agent as a stabilizer 6098 3 7/0753 contains that of the protein solution before adjustable freezing the solution has been added. 15. The method according to claim 14 , characterized in that starch dialdehyde is used as a crosslinking agent. 16. The method according to claim 15, characterized in that o, 5 "to Io wt. $ Starch dialdehyde, based on the Weight of protein, to be used. 17. The method according to claim 15 »characterized in that that 0.6 to 1.5 wt. £ of starch dialdehyde, based on the weight of the protein, are used. 18. Textured food product made by the method according to one of claims 1 to 17 « 609837/0753