A kind of organized soybean fiber protein combined with TG enzyme, preparation method and application

Abstract

The present invention discloses a kind of organized soybean filament protein combined with TG enzyme, preparation method and application, and the specific preparation steps include: 1) mixing: mixing soybean protein with wheat gluten, and then adding TG enzyme; 2) extrusion: the material obtained in step 1) is input into the cavity of a twin-screw extruder for extrusion organization treatment and high moisture extrusion to obtain soybean protein with a fibrous wire drawing structure; the protein content of the soybean protein is ≥90%; the extrusion organization treatment adopts a twin-screw extruder, the screw assembly mode is a high torque combination, the screw diameter is 36mm, and the aspect ratio is 24:1. The present invention combines TG enzyme to prepare organized soybean filament protein, which not only solves the organization problem of soybean filament protein, but also improves its application potential in plant meat substitutes.

Description

Technical Field

[0001] The invention belongs to the field of food processing technology / soybean functional protein structure application technology, and particularly relates to a TG enzyme-combined organized soybean filament protein, a preparation method and application thereof. Background Art

[0002] As the global plant protein market continues to grow, plant-based proteins are gaining more and more attention as meat substitutes. However, plant-based proteins are difficult to produce and there are challenges in generating fiber structures, which makes it challenging to simulate the production of alternative protein products with the texture of animal meat.

[0003] Texturized protein is a key ingredient in meat substitutes because it has the texture, taste and appearance required to be similar to plant meat, and is mainly obtained through extrusion processing technology. Low-moisture texturization of plant protein can be achieved through single-screw extrusion, but this method has problems such as low degree of organization, poor chewiness, easy expansion and lack of green label. High-moisture extrusion technology can make the prepared soy filament protein have a high degree of fiberization, a fibrous structure and taste similar to animal muscle. Moreover, high-moisture extrusion technology also has the advantages of low energy consumption, low emissions and high efficiency, and has been successfully applied to the manufacture of meat substitutes with meat-like texture. Alternative protein. However, considering that high-moisture extrusion is carried out in a fully enclosed barrel environment with high pressure and high temperature, it is difficult to visually observe the formation of the fiber structure, which poses challenges and sets obstacles to the production of organized soy protein with ideal texture.

[0004] In addition to being affected by the extrusion process, the quality of the final product is also closely related to the feed characteristics. Protein source, content and functional properties are key factors affecting the formation of the fiber structure of organized plant protein. Because the interaction between protein molecules is crucial to the formation of the fiber structure, a relatively high protein content is conducive to the formation of the fiber structure. Considering the raw material yield, price and functional properties, soy protein with a protein content of more than 90% is most commonly used in the production of high-moisture extruded plant protein meat. Moreover, unprocessed or less processed soy protein usually makes the final product darker and bitter, while the use of soy protein can improve the color and taste. By adding wheat gluten during high-moisture extrusion to promote the formation of disulfide bonds, the fiber structure of the protein product can be significantly improved. Adding wheat gluten as an auxiliary material during high-moisture extrusion can make the protein product have more ideal texture characteristics.

[0005] The present application found that enzymatic protein modification can effectively change the intramolecular and intermolecular cross-linking of proteins. Transglutaminase (TG enzyme) can catalyze the cross-linking between glutamine and lysine residues, thereby improving the viscosity, gelation, solubility and water holding capacity of proteins. The combination of high-moisture extrusion and TG enzyme modification for organizing plant proteins can significantly change the structure of proteins and their extrusion capacity. Therefore, the present application uses TG enzyme for the preparation of soybean filamentous protein. Summary of the invention

[0006] The present invention aims to solve the problem that soybean fibrous protein is not suitable for organization. Provided is an organized soybean fibrous protein combined with TG enzyme, a preparation method and application, which realizes the preparation of soybean protein fibrous fibrous structure and improves its application potential in plant meat substitutes.

[0007] The technical solution of the present invention is as follows:

[0008] A method for preparing textured soybean fibrous protein combined with TG enzyme, comprising the following steps:

[0009] 1) Mixing: Mix soy protein and wheat gluten, and then add TG enzyme;

[0010] 2) Extrusion: The material obtained in step 1) is input into the cavity of a twin-screw extruder for extrusion texturization treatment and high-moisture extrusion to obtain soybean protein with a fibrous drawing structure;

[0011] The protein content of the soy protein is ≥ 90%, preferably the protein content of the soy protein is 90% by weight;

[0012] The extrusion texturization process adopts a twin-screw extruder, the screw assembly method is a high-torque combination, the screw diameter is 36 mm, and the aspect ratio is 24:1.

[0013] Furthermore, in step 1), the mass ratio of the soy protein to the wheat gluten is 8.8:1.2 to 9:1.

[0014] Furthermore, in step 1), the added TG enzyme accounts for 0.18-0.22% of the total weight of the material.

[0015] Further, in step 2), the cavity includes zones I, II, III, IV, V, and VI distributed in sequence along the direction of material travel, the temperatures of zones II to VI are 60, 80, 145, 145, and 130° C., respectively, the screw speed is 240 rpm, the feed rate is 8 kg / h, the extrusion die cooling temperature is 70° C., and the moisture content of the material during the extrusion process is 60%. The textured soy fibrous protein prepared according to any of the methods.

[0016] Furthermore, the lateral shear force of the soybean fibrous protein is 2.09 kg, the longitudinal shear force is 1.33 kg, the fiberization degree is 1.84, the tensile strength is 0.55 kg, and the hardness is 21.6 kg.

[0017] The invention also discloses the application of the soybean fibrous protein in food processing, specifically in the field of vegetable meat.

[0018] Beneficial effects:

[0019] 1. Plant protein is mainly composed of globular proteins, and the forces that maintain its high-level spatial structure mainly rely on weak interactions such as non-covalent bonds or secondary bonds. The protein organization process mainly involves the change of weak interaction forces that maintain the high-level structure of proteins, as well as the change of protein conformation during extrusion. Globulin (mainly 11S) plays a key role in the formation of fiber structure; and TG enzyme modification can effectively affect the aggregation of globulin and the orientation of its fiber structure along the extrusion direction. During the extrusion cooking process, under the combined effects of temperature, shear, pressure and water, the high-level structure of natural globulin is destroyed, resulting in protein denaturation and structural reorganization. The protein molecule changes from a spherical structure to a linear structure, and the α-helix and β-fold become more stable structures, such as β-turns and random coils, thus forming an organizational structure similar to animal muscle fibers.

[0020] 2. High moisture extrusion is a continuous thermomechanical process. It uses a twin-screw extruder that rotates in the same direction and a cooling and shaping die. This technology can effectively reduce or prevent viscous energy dissipation and expansion, while promoting protein reconstruction, gelation, micro-coagulation, fat emulsification and fibrosis. Under high shear, pressure, humidity and temperature, soy protein undergoes a series of conformational changes, including molecular chain unfolding, association, aggregation and cross-linking, and may degrade or oxidize. During the extrusion cooking process, the interactions that maintain the original conformation of the protein will change, but the main chemical bonds such as peptide bonds usually do not change and remain stable. The mechanical shearing action of the screw exposes more sulfhydryl groups in the soy protein molecules, and forms disulfide bonds through oxidation reactions with the participation of oxygen, and finally forms high molecular weight protein aggregates. The soy protein aggregates are heated to a molten state and then transferred to a cooling die, which adjusts its natural molecular conformation. During the cooling process, if the protein aggregation rate and phase separation rate are almost equal, a lamellar and oriented fiber structure required for the replacement protein will be formed; if the protein aggregation rate is greater than the phase separation rate, a non-oriented gel structure will be formed.

[0021] 3. This technical solution not only solves the organization problem of soy protein, but also enhances its application potential in plant meat substitutes. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a process flow chart of a textured soybean fibrous protein and a preparation method thereof according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. The operations involved in the examples are all conventional technical operations in the art unless otherwise specified. The implementation conditions in the examples can be further adjusted according to specific experimental conditions or factory conditions. The implementation conditions not specified are usually the conditions in conventional experiments.

[0024] The following extrusion texturing process uses a FMHE36-24 twin-screw extruder; the screw assembly method is a high-torque combination, the screw diameter is 36mm, and the aspect ratio is 24:1.

[0025] Embodiment 1:

[0026] The basic physical and chemical indicators of the soy protein used are as follows:

[0027] protein Moisture carbohydrate Fat 90.0％ 6.2％ 2.0％ 0.8％

[0028] A method for preparing textured soybean protein, characterized by the following steps:

[0029] S1. Soy protein and wheat gluten with a purity of 85% are mixed at a mass ratio of 9:1. Then, the mixture is evenly mixed with TG enzyme so that the proportion of TG enzyme in the obtained material accounts for 0.2% of the total weight of the material.

[0030] S2. The material obtained in S1 is input into the cavity of a twin-screw extrusion system for extrusion organization treatment, wherein the cavity includes zones I, II, III, IV, V, and VI sequentially distributed along the direction of material travel, and the extrusion conditions adopted include: the temperatures of zones II to VI are 60, 80, 145, 145, and 130°C, respectively, the screw speed is 240rpm, the feed rate is 8kg / h, the extrusion die cooling temperature is 70°C, so that the moisture content of the material during the extrusion process is 60%.

[0031] The test results of the obtained textured soybean fiber protein are as follows:

[0032]

[0033] Embodiment 2:

[0034] The basic physical and chemical indicators of the soy protein used are as follows:

[0035] protein Moisture carbohydrate Fat 90.0％ 6.2％ 2.0％ 0.8％

[0036] A method for texturizing soybean protein, the specific operation steps are the same as those in Example 1, except that: in S1,

[0037] Soy protein was mixed with wheat gluten having a purity of 85% at a mass ratio of 9:1.

[0038] The test results of the obtained ordinary textured soybean fiber protein are as follows:

[0039]

[0040] It can be seen that the soybean protein with TG enzyme added in Example 1 has better transverse and longitudinal shear force, fiberization degree and hardness than the soybean protein without TG enzyme added in Example 2.

[0041] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing textured soybean fiber protein combined with TG enzyme, characterized in that: The following steps are involved: 1) Mixing: Mix soy protein and wheat gluten, and then add TG enzyme; 2) Extrusion: The material obtained in step 1) is input into the cavity of a twin-screw extruder for extrusion texturization treatment and high-moisture extrusion to obtain soybean protein with a fibrous drawing structure; The protein content of the soy protein is ≥90%; The extrusion texturization process adopts a twin-screw extruder, the screw assembly method is a high-torque combination, the screw diameter is 36 mm, and the aspect ratio is 24:

1.

2. The method for preparing textured soybean protein according to claim 1, characterized in that: In step 1), the mass ratio of the soy protein to the wheat gluten is 8.8:1.2 to 9:

1.

3. The method for preparing textured soybean protein according to claim 1, characterized in that: In step 1), the added TG enzyme accounts for 0.18-0.22% of the total weight of the material.

4. The method for preparing textured soybean protein according to claim 1, characterized in that: In step 2), the cavity includes zones I, II, III, IV, V, and VI distributed in sequence along the direction of material travel, the temperatures of zones II to VI are 60, 80, 145, 145, and 130°C, respectively, the screw speed is 240 rpm, the feed rate is 8 kg / h, the extrusion die cooling temperature is 70°C, and the high moisture extrusion is to make the moisture content of the material during the extrusion process be 60%.

5. The textured soybean fibrous protein prepared according to the method as described in any one of claims 1 to 4.

6. The soybean fibrous protein according to claim 5, characterized in that: The soybean fibrous protein has a transverse shear force of 2.09 kg, a longitudinal shear force of 1.33 kg, a fiberization degree of 1.84, a tensile strength of 0.55 kg, and a hardness of 21.6 kg.

7. Use of the soybean fibrous protein according to claim 5 or 6 in food processing.

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