Method for preparing soybean protein hydrolysate-polysaccharide composite gel based on enzymolysis treatment

Abstract

The invention discloses a method for preparing soybean protein hydrolysate-polysaccharide composite gel based on enzymolysis treatment, and belongs to the technical field of food processing and manufacturing. According to the method for preparing the soybean protein hydrolysate-polysaccharide composite gel based on the enzymolysis treatment, the soybean protein hydrolysate is prepared by performing enzymolysis treatment on the soybean protein through papain, and meanwhile, the polysaccharide is added in an auxiliary manner, so that a theoretical basis is laid for actual production and industrial application of soybean protein products with excellent gel property. The main process comprises the following steps: (1) carrying out extrusion puffing treatment and enzymolysis; (2) spray drying; (3) papain treatment; (4) adding carrageenan; and (5) heating, cooling and molding. The gel property of the soybean protein is effectively improved through the action of the papain and the addition of the polysaccharide, better economic benefits can be created for soybean gel products and the processing industry of the soybean gel products, development of the technical field of food processing and manufacturing is promoted, and remarkable economic and social benefits are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing and manufacturing, and particularly relates to a method for preparing a soybean protein hydrolyzate-polysaccharide composite gel based on enzymatic treatment. Background Art

[0002] Soy protein has been widely recognized to have good nutritional value, functional properties, and even health effects, including the effect of lowering serum cholesterol. At present, my country is short of high-quality protein resources. With the development of the economy, soy protein has attracted widespread attention because of its good quality, low price, rich nutritional value and balanced amino acid composition. However, the functional properties of soy protein have certain limitations in industrial production applications. The rational use of various modification methods to obtain soy protein with excellent solubility, gel properties and other functional properties is one of the main research directions at present.

[0003] The complex of protein and polysaccharide can strengthen the intermolecular interactions, including hydrogen bonds, disulfide bonds, hydrophobic interactions and electrostatic interactions, and can enhance the strength of the gel. Proteins and polysaccharides belong to different categories of biopolymers, showing great differences in chemical structure, physical properties and functions. Therefore, a wider range of phase behaviors can be produced in the mixture of protein and polysaccharide. Depending on factors such as pH value, ionic strength, protein-polysaccharide ratio and biopolymer content, two types of interactions may occur in the mixed solution of protein and polysaccharide. When the protein and polysaccharide are thermodynamically compatible, the two undergo associative phase separation; when the protein and polysaccharide are thermodynamically incompatible, the two undergo separation phase separation. At present, a large number of studies have shown that the gel properties of appropriately modified proteins can be significantly improved after being complexed with polysaccharides.

[0004] Gel-type foods are very common in daily life, such as jelly and ham. Most food gels are mixed gels, because they usually contain a variety of biopolymers to provide different functional properties, such as adding a variety of proteins to provide different nutritional values, and adding a variety of polysaccharides to improve the strength and stability of the gel. The gelation of proteins is mainly divided into physical induced gelation (heat and pressure) and chemical induced gelation (acid, ion and enzyme). The gelation process is usually that the protein structure unfolds under the action of external driving force, and then the unfolded protein aggregates to form an ordered three-dimensional aggregate network cross-linked by covalent bonds and non-covalent bonds.

[0005] There are many ways to modify soy protein, such as heat treatment, ultrasonic treatment, pH shift treatment, enzymatic treatment, etc. Among them, the mechanism of enzymatic treatment of modified soy protein is to hydrolyze soy protein by protease, so that its amino acid residues and polypeptide chains change, change its spatial structure, and thus improve surface hydrophobicity. At the same time, enzymatic hydrolysis can increase intramolecular or intermolecular cross-linking or connect special functional groups. In recent years, many studies have shown that enzymatic treatment of soy protein and polysaccharide combined with soy protein can improve the gel properties of soy protein products.

[0006] Considering that soy protein products, which are widely favored by the food and health care products industries due to their high nutritional value, have poor gel properties, the present invention uses papain to enzymatically hydrolyze soy protein to prepare protein hydrolysate, and at the same time assists in adding polysaccharides, thereby giving soy protein significant gel properties. This opens up a better prospect for the use of soy protein as a food ingredient and functional food formulation, and broadens the application of soy protein hydrolysate-polysaccharide complexes in the food field. Summary of the invention

[0007] The purpose of the present invention is to solve the above-mentioned technical problems and overcome the shortcomings of the prior art. The present invention provides a method for preparing a soybean protein hydrolyzate-polysaccharide composite gel based on enzymatic treatment. The soybean protein is hydrolyzed by papain and polysaccharides are added as an auxiliary, thereby laying a theoretical basis for the actual production and industrial application of a soybean protein product with excellent gel properties.

[0008] The preparation method of the present invention is as follows:

[0009] (1) cleaning and flaking soybeans, and then performing extrusion puffing pretreatment to obtain puffed materials, and mixing the puffed materials with water to obtain a mixed solution; adjusting the water bath temperature to 55-65° C., adjusting the pH to 9.0, adding alkaline protease for enzymolysis, and performing enzymolysis for 120-150 minutes to obtain an enzymolysis solution;

[0010] (2) After the enzymatic hydrolyzate is inactivated, the hydrolyzate is collected after centrifugal separation, and spray-dried at an inlet temperature of 175-180° C. and an outlet temperature of 80-85° C. to obtain hydroenzymatic soybean protein;

[0011] (3) dissolving soybean protein in deionized water, stirring at room temperature for 2 h to fully dissolve it, adjusting the pH to 7.0, and hydrating at 4° C. overnight to prepare a soybean protein solution;

[0012] (4) subjecting the final soy protein solution of step (3) to papain enzymatic hydrolysis, dissolving carrageenan in deionized water after enzymatic hydrolysis, stirring evenly, heating in a water bath at 60° C. for 15 min, and then adding the carrageenan to the soy protein solution after enzymatic hydrolysis, placing the carrageenan on a magnetic stirrer while stirring to fully dissolve the soy protein hydrolyzate-polysaccharide mixture;

[0013] (5) placing the soy protein hydrolysate-polysaccharide mixed solution described in step (4) into a water bath and heating it to obtain a composite gel, rapidly cooling it to 4° C. after heating, and standing it for 6 to 8 hours to obtain a soy protein hydrolysate-polysaccharide composite gel.

[0014] It is further defined that the amount of alkaline protease added in step (1) is 6-8% of the mass of the mixed solution. ;

[0015] It is further defined that the enzyme inactivation temperature in step (2) is 90-95°C, and the centrifugation conditions are 2000 rpm, 4°C, 20 min;

[0016] It is further defined that the concentration of the soy protein solution in step (3) is 50-60 mg / mL;

[0017] It is further defined that the enzymatic treatment conditions in step (4) are pH 8.0, 55° C., E / S=0.5%, the enzymatic hydrolysis time is 10-20 min, and the carrageenan concentration is 1.5%.

[0018] It is further defined that the water bath heating condition in step (5) is heating at 60° C. for 1 h.

[0019] Beneficial effects: Compared with single soybean protein and its products, the soybean protein hydrolysate-polysaccharide composite gel prepared by the present invention has significantly improved gel properties. The present invention uses papain to enzymatically hydrolyze soybean protein to prepare protein hydrolysate, and simultaneously assists in adding polysaccharides, which can create better economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is the process diagram of soybean protein hydrolysate-polysaccharide composite gel. Specific embodiments

[0021] The soybeans used in the present invention were purchased from Heilongjiang Beidahuang Group, and other auxiliary materials were purchased from laboratory cooperative merchants. The specific embodiments of the present invention are described in detail below.

[0022] Example 1.

[0023] A method for preparing a soybean protein hydrolysate-polysaccharide composite gel based on enzymatic treatment, characterized in that the preparation method is as follows:

[0024] (1) cleaning and flaking soybeans, and then performing extrusion puffing pretreatment to obtain puffed materials, and mixing the puffed materials with water to obtain a mixed solution; adjusting the water bath temperature to 60° C., adjusting the pH to 9.0, adding alkaline protease for enzymolysis (enzyme addition amount 7‰), and performing enzymolysis for 135 minutes to obtain an enzymolysis solution;

[0025] (2) inactivating the enzyme in the enzymatic hydrolyzate at 95° C., centrifuging (2000 rpm, 4° C., 20 min) and collecting the hydrolyzate, spray drying the hydrolyzate at an inlet temperature of 180° C. and an outlet temperature of 85° C., to obtain hydroenzymatic soybean protein;

[0026] (3) Dissolve the soy protein in deionized water, stir at room temperature for 2 h to fully dissolve it, adjust the pH to 7.0, and hydrate at 4°C overnight to prepare a 60 mg / mL soy protein solution;

[0027] (4) The final soy protein solution of step (3) is subjected to papain enzymolysis treatment (pH 8.0, 55° C., E / S=0.5%, 10 min), and after the enzymolysis treatment, carrageenan (concentration of 1.5%) is dissolved in deionized water, stirred evenly, heated in a 60° C. water bath for 20 min, and then added to the soy protein solution after the enzymolysis treatment, and the soy protein solution is placed on a magnetic stirrer and stirred while being added to fully dissolve, thereby obtaining a soy protein hydrolyzate-polysaccharide mixed solution;

[0028] (5) placing the soy protein hydrolysate-polysaccharide mixed solution described in step (4) into a water bath and heating it at 60° C. for 1 h to obtain a composite gel, which was then rapidly cooled to 4° C. after heating and allowed to stand for 6 h to obtain a soy protein hydrolysate-polysaccharide composite gel.

[0029] Example 2.

[0030] A method for preparing a soybean protein hydrolysate-polysaccharide composite gel based on enzymatic treatment, characterized in that the preparation method is as follows:

[0031] (1) cleaning and flaking soybeans, and then performing extrusion puffing pretreatment to obtain puffed materials, and mixing the puffed materials with water to obtain a mixed solution; adjusting the water bath temperature to 65° C., adjusting the pH to 9.0, adding alkaline protease for enzymolysis (enzyme addition amount 8‰), and performing enzymolysis for 125 minutes to obtain an enzymolysis solution;

[0032] (2) inactivating the enzyme in the enzymatic hydrolyzate at 90° C., collecting the hydrolyzate after centrifugation (2000 rpm, 4° C., 20 min), and spray drying the hydrolyzate at an inlet temperature of 175° C. and an outlet temperature of 80° C. to obtain hydroenzymatic soybean protein;

[0033] (3) Dissolve the soy protein in deionized water, stir at room temperature for 2 h to fully dissolve it, adjust the pH to 7.0, and hydrate at 4°C overnight to prepare a 50 mg / mL soy protein solution;

[0034] (4) The final soybean protein solution of step (3) is subjected to papain enzymolysis treatment (pH 8.0, 55° C., E / S=0.5%, 20 min), and carrageenan (concentration of 1.5%) is dissolved in deionized water after enzymolysis treatment, stirred evenly, and added to the soybean protein solution after enzymolysis treatment after heating in a 60° C. water bath for 20 min, and the solution is placed on a magnetic stirrer and stirred while being added to fully dissolve, thereby obtaining a soybean protein hydrolyzate-polysaccharide mixed solution;

[0035] (5) placing the soy protein hydrolysate-polysaccharide mixed solution described in step (4) into a water bath and heating it at 60° C. for 1 h to obtain a composite gel, which was then rapidly cooled to 4° C. after heating and allowed to stand for 8 h to obtain a soy protein hydrolysate-polysaccharide composite gel.

[0036] The following experiment was used to verify the experimental effect: Example 2 was used to verify the experimental effect:

[0037] 1. The indicators are determined as follows:

[0038] The obtained soybean protein hydrolysate-polysaccharide composite gel was cooled to 4°C and allowed to stand for 8 hours, then the soybean protein hydrolysate-polysaccharide gel complex was taken out and its gel strength and water holding capacity were measured.

[0039] 2. Results Analysis

[0040] Ordinary soybean protein-polysaccharide solution: gel strength is 214.53g; water holding rate is 74.09%;

[0041] Example 2: Gel strength is 675.17 g; water holding capacity is 97.34%;

[0042] As analyzed above, the preparation of soybean protein hydrolysate-polysaccharide composite gel by papain enzymatic treatment can significantly improve the gel strength and water holding rate of soybean protein.

Claims

1. A method for preparing a soybean protein hydrolysate-polysaccharide composite gel based on enzymatic treatment, characterized in that: The preparation method is as follows: (1) cleaning and flaking soybeans, and then performing extrusion puffing pretreatment to obtain puffed materials, and mixing the puffed materials with water to obtain a mixed solution; adjusting the water bath temperature to 55-65° C., adjusting the pH to 9.0, adding alkaline protease for enzymolysis, and performing enzymolysis for 120-150 minutes to obtain an enzymolysis solution; (2) After the enzymatic hydrolyzate is inactivated, the hydrolyzate is collected after centrifugal separation, and spray-dried at an inlet temperature of 175-180° C. and an outlet temperature of 80-85° C. to obtain hydroenzymatic soybean protein; (3) dissolving soybean protein in deionized water, stirring at room temperature for 2 h to fully dissolve it, adjusting the pH to 7.0, and hydrating at 4° C. overnight to prepare a soybean protein solution; (4) subjecting the final soy protein solution of step (3) to papain enzymatic hydrolysis, dissolving carrageenan in deionized water after enzymatic hydrolysis, stirring evenly, heating in a water bath at 60° C. for 15 min, and then adding the carrageenan to the soy protein solution after enzymatic hydrolysis, placing the carrageenan on a magnetic stirrer while stirring to fully dissolve the soy protein hydrolyzate-polysaccharide mixture; (5) placing the soy protein hydrolysate-polysaccharide mixed solution described in step (4) into a water bath and heating it to obtain a composite gel, rapidly cooling it to 4° C. after heating, and standing it for 6 to 8 hours to obtain a soy protein hydrolysate-polysaccharide composite gel.

2. The preparation method according to claim 1, characterized in that: The amount of alkaline protease added in step (1) is 6-8‰ of the mass of the mixed solution.

3. The preparation method according to claim 1, characterized in that: The enzyme inactivation temperature in step (2) is 90-95°C, and the centrifugation conditions are 2000rpm, 4°C, and 20min.

4. The preparation method according to claim 1, characterized in that: The concentration of the soy protein solution in step (3) is 50-60 mg / mL.

5. The preparation method according to claim 1, characterized in that: The enzymatic hydrolysis treatment conditions in step (4) are pH 8.0, 55° C., E / S=0.5%, the enzymatic hydrolysis time is 10-20 min, and the carrageenan concentration is 1.5%.

6. The preparation method according to claim 1, characterized in that: The water bath heating condition in step (5) is heating at 60° C. for 1 h.

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