Preparation method of modified oat protein

Abstract

The invention discloses a preparation method and application of modified oat protein, and belongs to the technical field of food processing. According to the invention, the avenin is extracted by combined use of microwave treatment and high-pressure extraction, and the modified avenin is prepared by combined use of succinylation modification and ultrasonic treatment; the method mainly comprises the following steps: pretreatment, dissolution, microwave treatment, extraction, centrifugation, modification, purification, concentration, drying and crushing to finally obtain the modified oat protein. According to the method, the oat protein is extracted in a manner of combining microwave treatment and high-pressure extraction, so that the extraction efficiency and purity of the oat protein are improved; the avenin is modified by adopting a succinylation mode, so that the solubility of the avenin is improved; a manner of combining succinylation, PBS (Phosphate Buffer Solution) and ultrasonic treatment is adopted for modification, so that the modification efficiency is further improved; compared with conventional avenin, the modified avenin prepared by the method has better dispersity and solubility.

Description

Technical Field

[0001] The invention relates to a method for preparing and modifying oat protein, and belongs to the technical field of food processing. Background Art

[0002] Oat protein, a cereal-derived plant protein, boasts the highest protein content among cereals and a well-balanced amino acid profile, with various amino acid contents approaching or exceeding FAO / WHO standards. Its chemical score (CS) is as high as 0.54, and its biological value (BV) is 72-75, placing it at the forefront of plant protein nutritional value. Furthermore, oat protein boasts advantages such as a small molecular weight and ease of digestion and absorption, making it a high-quality plant protein comparable to animal protein, offering significant potential for development in the health food sector.

[0003] The conventional extraction methods of plant protein are mainly alkali dissolution and acid precipitation and enzymatic methods. In addition to the strict process conditions, a large amount of chemical reagents are also required. While affecting the flavor of the product, it is also easy to produce a large amount of wastewater, which puts a certain amount of pressure on the environment. Therefore, a combination of multiple physical means can be used to extract oat protein, which can minimize the damage to the natural structure of the protein and the impact on the flavor. In addition, although oat protein has many advantages, like most other natural plant proteins, its functional properties have certain limitations, such as solubility and stability. Therefore, it is necessary to carry out targeted modification of its functional properties to achieve better processing characteristics. At present, the most commonly used modification method is chemical modification, but a single modification treatment often has disadvantages such as low modification efficiency and instability, because it is necessary to adopt a combination of multiple modification methods to achieve the desired effect. Summary of the Invention

[0004] Purpose of the invention:

[0005] In order to solve the problems of poor solubility of oat protein and the resulting rough taste and poor stability in food, the present invention provides a method for preparing oat protein. The method uses microwave treatment and high-pressure extraction to extract oat protein, thereby achieving efficient and rapid extraction of oat protein, improving the extraction efficiency and purity of oat protein, and modifying the oat protein by combining succinylation and ultrasonic treatment to improve the modification efficiency and the solubility of the oat protein.

[0006] Technical solution:

[0007] In order to solve the above problems, the present invention adopts the following technical solutions:

[0008] A preparation method and application of modified oat protein, comprising the following steps:

[0009] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0010] (2) Dissolving: slowly dissolve the oatmeal powder in distilled water by stirring to prepare an oatmeal liquid;

[0011] (3) Microwave: The oat liquid is subjected to microwave treatment;

[0012] (4) Extraction: Using CO2 to perform high-pressure extraction on the microwave-treated oat liquid;

[0013] (5) Centrifugation: The extracted liquid is centrifuged and the supernatant is collected;

[0014] (6) Modification: The supernatant was succinylated and ultrasonically treated;

[0015] (7) Purification: Purify the feed solution using a dialysis bag;

[0016] (8) Concentration: The purified liquid is concentrated at low pressure using a rotary evaporator;

[0017] (9) Drying: The concentrated liquid is subjected to vacuum freeze drying;

[0018] (10) Pulverization: The dried sample is finely pulverized to obtain oat protein powder.

[0019] In the above steps, the ratio of oatmeal powder to water in step (2) is 1:10-1:20 (w / v), the stirring temperature is 45-50° C., and the stirring time is 0.5-1 h.

[0020] The microwave power in step (3) is 500-1000W, the treatment time is 2-4h, and the temperature is 20-25°C;

[0021] The extraction pressure in step (4) is 10-30 MPa, the extraction temperature is 30-60° C., and the extraction time is 1-4 h;

[0022] The centrifugal force in step (5) is 3000-5000g, and the time is 10-20min;

[0023] The succinylation modification reagent in step (6) is succinic anhydride, the addition amount is 0.3-0.5% (w / w), the stirring speed is 200-300 rpm, the reaction pH is 8-9, the reaction temperature is 20-25°C, and the reaction time is 1-2h;

[0024] The purification method in step (7) is to use a dialysis bag for purification, the dialysis time is 24-48 hours, and the molecular weight of the dialysis bag is 8000-10000Da;

[0025] The rotary evaporation temperature in step (8) is 50-60° C. and the time is 1-2 h;

[0026] The drying in step (9) is vacuum freeze drying, the drying temperature is -40°C, and the drying time is 12-24h;

[0027] The crushing mesh size in step (10) is 80-100 mesh.

[0028] Beneficial effects:

[0029] The present invention provides a preparation method and application of modified oat protein. Oat protein is extracted by microwave treatment and high-pressure extraction, thereby improving the extraction efficiency and purity of the protein while reducing the impact on the natural structure and flavor of the oat protein. Succinylation treatment is used for modification to improve the dispersibility and solubility of the oat protein. Combining with ultrasonic treatment further improves the modification efficiency, thereby providing a new method for preparing modified oat protein. The protein beverage of the present invention has better taste and stability. DETAILED DESCRIPTION

[0030] The present invention will be further described below with reference to specific embodiments.

[0031] Test method:

[0032] 1. Determination of Protein Content

[0033] The determination of protein content in oat protein is carried out in accordance with the National Standard of the People's Republic of China GB5009.5-2016 "National Food Safety Standard Determination of Protein in Food", using the Kjeldahl method, and the protein coefficient is 5.83.

[0034] Example 1

[0035] A method for preparing oat protein comprises the following steps:

[0036] Pretreatment → dissolution → microwave → centrifugation → purification → concentration → drying → crushing

[0037] The specific steps are as follows:

[0038] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0039] (2) Dissolution: Add 10 times the mass of distilled water to the oatmeal powder and slowly stir to dissolve it to prepare an oatmeal liquid;

[0040] (3) Microwave: The oatmeal solution was treated with microwaves using a microwave reactor (XH-8000Pro) at a power of 800 W for 3 h.

[0041] (4) Centrifugation: The microwaved liquid was centrifuged at 3000 g for 20 min, and the supernatant was collected;

[0042] (5) Purification: The feed solution (i.e., the supernatant was placed in the dialysis bag) was purified for 24 h using an 8000 Da dialysis bag. PBS buffer was used as the dialysate at 20°C. After the purification, the retentate (in the dialysis bag) was collected.

[0043] (6) Concentration: The purified liquid was concentrated using a rotary evaporator at 50°C for 1 h;

[0044] (7) Drying: The concentrated liquid was freeze-dried at -40°C for 24 h;

[0045] (8) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0046] Example 2

[0047] A method for preparing oat protein comprises the following steps:

[0048] Pretreatment → dissolution → microwave → extraction → centrifugation → purification → concentration → drying → crushing

[0049] The specific steps are as follows:

[0050] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0051] (2) Dissolution: Add 15 times the mass of distilled water to the oatmeal powder and slowly stir to dissolve it to prepare an oatmeal liquid;

[0052] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0053] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 supercritical fluid extraction (Siphon-50) at 10 MPa for 2 h, a flow rate of 20 kg / h, and an extraction temperature of 40°C;

[0054] (5) Centrifugation: The extracted solution was centrifuged at 4000 g for 15 min, and the supernatant was collected;

[0055] (6) Purification: The feed solution was purified using a 10,000 Da dialysis bag for 36 h;

[0056] (7) Concentration: The purified liquid was concentrated using a rotary evaporator at 55°C for 1.5 h;

[0057] (8) Drying: The concentrated liquid was freeze-dried at -40°C for 36 h;

[0058] (9) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0059] Example 3

[0060] A method for preparing oat protein comprises the following steps:

[0061] Pretreatment → dissolution → microwave → extraction → centrifugation → purification → concentration → drying → crushing

[0062] The specific steps are as follows:

[0063] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0064] (2) Dissolution: Add 20 times the mass of distilled water to the oat powder and slowly stir to dissolve to prepare an oat liquid;

[0065] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0066] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 supercritical fluid extraction (Siphon-50) at 25 MPa for 2 h, a flow rate of 25 kg / h, and an extraction temperature of 40°C;

[0067] (5) Centrifugation: The microwaved liquid was centrifuged at 5000 g for 20 min, and the supernatant was collected;

[0068] (6) Purification: The feed solution was purified using a 10,000 Da dialysis bag for 48 h;

[0069] (7) Concentration: The purified liquid was concentrated using a rotary evaporator at 60°C for 2 h;

[0070] (8) Drying: The concentrated liquid was freeze-dried at -40°C for 48 h;

[0071] (9) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0072] Example 4

[0073] A method for preparing oat protein comprises the following steps:

[0074] Pretreatment → dissolution → microwave → extraction → centrifugation → purification → concentration → drying → crushing

[0075] The specific steps are as follows:

[0076] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0077] (2) Dissolution: Add 15 times the mass of distilled water to the oatmeal powder and slowly stir to dissolve it to prepare an oatmeal liquid;

[0078] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0079] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 supercritical fluid extraction (Siphon-50) at 25 MPa for 2 h, a flow rate of 25 kg / h, and an extraction temperature of 50 °C;

[0080] (5) Centrifugation: The extracted solution was centrifuged at 4000 g for 10 min, and the supernatant was collected;

[0081] (6) Purification: The feed solution was purified using an 8000Da dialysis bag for 36 hours;

[0082] (7) Concentration: The purified liquid was concentrated using a rotary evaporator at 55°C for 2 h;

[0083] (8) Drying: The concentrated liquid was freeze-dried at -40°C for 48 h;

[0084] (9) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0085] Comparative Example 1

[0086] A method for preparing oat protein comprises the following steps:

[0087] Pretreatment → dissolution → alkali dissolution → centrifugation → acid precipitation → centrifugation → neutralization → drying → crushing

[0088] The specific steps are as follows:

[0089] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0090] (2) Dissolution: Add 10 times the mass of distilled water to the oatmeal powder and slowly stir to dissolve it to prepare an oatmeal liquid;

[0091] (3) Alkali dissolution: slowly adjust the pH of the oatmeal solution to 8.0 and continue stirring at room temperature for 1 h;

[0092] (4) Centrifugation: The oatmeal solution was centrifuged at 2000 g for 20 min, and the supernatant was collected;

[0093] (5) Acid precipitation: The pH of the collected supernatant was slowly adjusted to 4.0 and stirred continuously at room temperature for 1.0 h;

[0094] (6) Centrifugation: The oatmeal solution was centrifuged at 3000 g for 10 min, and the precipitate was collected;

[0095] (7) Neutralization: Add water to the collected precipitate and adjust the pH to 6.8;

[0096] (8) Drying: The neutralized liquid was freeze-dried at -40 °C for 24 h;

[0097] (9) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0098] Comparative Example 2

[0099] A method for preparing oat protein comprises the following steps:

[0100] Pretreatment → dissolution → enzymatic hydrolysis → centrifugation → purification → drying → crushing

[0101] The specific steps are as follows:

[0102] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0103] (2) Dissolution: Add 20 times the mass of distilled water to the oat powder and slowly stir to dissolve to prepare an oat liquid;

[0104] (3) Enzymatic hydrolysis: The pH of the oat solution was slowly adjusted to 7.2, 800 U / g neutral protease was added, and stirring was continued at 50 °C for 2 h;

[0105] (4) Centrifugation: The oatmeal solution was centrifuged at 5000 g for 20 min, and the supernatant was collected;

[0106] (5) Purification: The collected supernatant was purified using a 10,000 Da dialysis bag for 48 h;

[0107] (6) Drying: The purified liquid was freeze-dried at -40 °C for 24 h;

[0108] (7) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0109] Table 1 shows the oat protein content in samples after different treatment processes. As can be seen from Table 1, high-pressure extraction significantly increased both the oat protein content and protein yield. This is primarily due to the rapid, uniform heating provided by microwave treatment, which accelerated the desorption and diffusion of oat protein. High-pressure extraction, on the other hand, enhanced the solubility of oat protein, further promoting its extraction efficiency and shortening extraction time. After 3 hours of treatment at 800W microwave power, the oat protein content and yield were the highest, surpassing those obtained with enzymatic preparation. The results were not significantly different from those obtained with alkali dissolution and acid precipitation. This also reduced the use of chemical reagents such as acids and alkalis, as well as the discharge of wastewater, contributing to cost savings and reduced environmental impact.

[0110] Table 1 Oat protein content in samples after different treatment processes

[0111]

[0112]

[0113] Note: Different lowercase letters in the same column indicate significant differences between corresponding data (P<0.05).

[0114] Example 5

[0115] A method for preparing oat protein comprises the following steps:

[0116] The specific steps of pretreatment → dissolution → microwave → extraction → centrifugation → modification → purification → concentration → drying → crushing are as follows:

[0117] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0118] (2) Dissolution: Add 15 times the mass of distilled water to the oatmeal powder and slowly stir to dissolve it to prepare an oatmeal liquid;

[0119] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0120] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 at 25 MPa for 3 h at an extraction temperature of 50°C;

[0121] (5) Centrifugation: The microwaved liquid was centrifuged at 4000 g for 15 min, and the supernatant was collected;

[0122] (6) Modification: The collected supernatant was subjected to succinylation modification. The modification reagent was succinic anhydride, the addition amount was 0.3% (w / w), the reaction pH was 8, the stirring speed was 200 rpm, the reaction temperature was 20°C, and the reaction time was 1 h;

[0123] (7) Purification: The feed solution was purified using an 8000Da dialysis bag for 24 h;

[0124] (8) Concentration: The purified liquid was concentrated using a rotary evaporator at 50°C for 1 h;

[0125] (9) Drying: The concentrated liquid was freeze-dried at -40°C for 24 h;

[0126] (10) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0127] Example 6

[0128] A method for preparing oat protein comprises the following steps:

[0129] The specific steps of pretreatment → dissolution → microwave → extraction → centrifugation → modification → purification → concentration → drying → crushing are as follows:

[0130] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0131] (2) Dissolution: Add 20 times the mass of distilled water to the oat powder and slowly stir to dissolve to prepare an oat liquid;

[0132] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0133] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 at 25 MPa for 3 h at an extraction temperature of 50°C;

[0134] (5) Centrifugation: The microwaved liquid was centrifuged at 5000 g for 20 min, and the supernatant was collected;

[0135] (6) Modification: The collected supernatant was subjected to succinylation modification. The modification reagent was succinic anhydride, the addition amount was 0.3% (w / w), and 0.15 M PBS buffer was added. The reaction pH was 8, the stirring speed was 200 rpm, the reaction temperature was 20°C, and the reaction time was 1 h.

[0136] (7) Purification: The feed solution was purified using an 8000Da dialysis bag for 24 h;

[0137] (8) Concentration: The purified liquid was concentrated using a rotary evaporator at 50°C for 1 h;

[0138] (9) Drying: The concentrated liquid was freeze-dried at -40°C for 24 h;

[0139] (10) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0140] Example 7

[0141] A method for preparing oat protein comprises the following steps:

[0142] Pretreatment → dissolution → microwave → extraction → centrifugation → modification → purification → concentration → drying → crushing

[0143] The specific steps are as follows:

[0144] (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder;

[0145] (2) Dissolution: Add 20 times the mass of distilled water to the oat powder and slowly stir to dissolve to prepare an oat liquid;

[0146] (3) Microwave: The oatmeal solution was microwaved at 800W for 3 h;

[0147] (4) Extraction: The microwave-treated oat liquid was subjected to high-pressure extraction using CO2 at 25 MPa for 3 h at an extraction temperature of 50°C;

[0148] (5) Centrifugation: The microwaved liquid was centrifuged at 5000 g for 20 min, and the supernatant was collected;

[0149] (6) Modification: The collected supernatant was subjected to succinylation modification using succinic anhydride as the modification reagent at a concentration of 0.5% (w / w). 0.15 M PBS buffer was added. The reaction pH was 9, the stirring speed was 300 rpm, the reaction temperature was 25°C, the reaction time was 2 h, and ultrasonic treatment was applied at a power of 1000 W.

[0150] (7) Purification: The feed solution was purified using a 10,000 Da dialysis bag for 48 h;

[0151] (8) Concentration: The purified liquid was concentrated using a rotary evaporator at 60°C for 2 h;

[0152] (9) Drying: The concentrated liquid was freeze-dried at -40°C for 48 h;

[0153] (10) Grinding: The dried sample is finely ground into 80-100 mesh to obtain oat protein powder.

[0154] The solubility of oat protein in samples after different process treatments can be seen in Table 2. As can be seen from Table 2, the unmodified oat proteins all showed poor solubility, and a large amount of lumps would appear during dissolution. However, after succinylation modification, the solubility of the oat protein samples was effectively improved, and the lumps during dissolution were significantly reduced. After combined with ultrasonic treatment, the solubility of the oat protein samples was further improved, and almost no lumps appeared during the dissolution process. Through succinylation modification, succinic anhydride is reacted with the amino groups in the protein, thereby introducing succinyl groups on the protein molecules, enhancing the interaction between the protein molecules and the water molecules, and thus improving the solubility of the protein. At the same time, the cavitation effect and mechanical effect of ultrasound can promote the succinylation reaction, so that more succinyl groups are combined with the protein molecules, thereby improving the modification efficiency. Furthermore, in Examples 6 and 7, we also added an auxiliary modifier 0.1-0.2M PBS buffer and found that the solubility performance can be further improved.

[0155] Table 2 Dissolution of oat protein after different treatment processes

[0156]

[0157] Example 8

[0158] This embodiment provides an application of oat protein in beverages, and the steps are as follows:

[0159] Mixing → Dissolving → Homogenizing → Sterilizing → Cooling → Canning

[0160] The specific steps are as follows:

[0161] (1) Mixing: Take 1% of the oat protein in Examples 4-7 and Comparative Examples 1-2, and dry-mix with 5% white sugar, 0.1% sodium carboxymethyl cellulose, 0.075% xanthan gum, 0.075% locust bean gum, etc. and mix well for later use;

[0162] (2) Dissolution: Add the mixed powder material to water and stir at high speed for 10 minutes to make a homogenous slurry;

[0163] (3) Homogenization: The slurry is homogenized using a high-pressure homogenizer at a pressure of 15 MPa;

[0164] (4) Sterilization: sterilize the material at 88°C for 15 minutes;

[0165] (5) Cooling: Cool to room temperature and can.

[0166] Table 3 Comparison of beverages prepared with different oat proteins

[0167]

[0168] The comparative results of beverages prepared from different oat proteins can be seen in Table 3. As can be seen from Table 3, beverages prepared from modified oat proteins have better taste and storage stability, and the combined modification method has better effects than single modification. This is mainly because the solubility of the modified oat protein is greatly improved, so that it can show better functional properties in beverages. Therefore, when preparing modified oat protein by combining microwave treatment and high-pressure extraction and combining succinylation modification and ultrasonic treatment, it is preferred to extract oat protein by combining microwave treatment and high-pressure extraction, and it is preferred to modify oat protein by combining succinylation + PBS with ultrasonic treatment to prepare modified oat protein. The prepared oat protein has a higher protein content and protein yield than those prepared by alkali dissolution, acid precipitation and enzymatic method, and has better solubility than conventional oat protein. Beverages prepared from modified oat protein also have better taste and storage stability.

[0169] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A preparation method of modified oat protein and its application, characterized in that: The following steps are involved: (1) Pretreatment: cleaning, removing impurities, drying, and crushing the oat raw materials to make oat powder; (2) Dissolving: slowly dissolve the oatmeal powder in distilled water by stirring to prepare an oatmeal liquid; (3) Microwave: The oat liquid is subjected to microwave treatment; (4) Extraction: Using CO2 to perform high-pressure extraction on the microwave-treated oat liquid; (5) Centrifugation: The extracted liquid is centrifuged and the supernatant is collected; (6) Modification: The supernatant was succinylated and ultrasonically treated; (7) Purification: Purify the feed solution using a dialysis bag; (8) Concentration: The purified liquid is concentrated at low pressure using a rotary evaporator; (9) Drying: The concentrated liquid is subjected to vacuum freeze drying; (10) Pulverization: The dried sample is finely pulverized to obtain oat protein powder.

2. The preparation method and application of a modified oat protein according to claim 1, characterized in that: In step (2), the ratio of oatmeal powder to water is 1:10-1:20 (w / v), the stirring temperature is 45-50° C., and the stirring time is 0.5-1 h.

3. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The microwave power in step (3) is 500-1000W, the treatment time is 2-4h, and the temperature is 20-25°C.

4. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The extraction pressure in step (4) is 10-50 MPa, the extraction temperature is 20-60° C., and the extraction time is 1-4 h.

5. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The centrifugal force in step (5) is 3000-5000g, and the time is 10-20min.

6. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The succinylation modification reagent in step (6) is succinic anhydride, the addition amount is 0.3-0.5% (w / w), the reaction pH is 8-9, the stirring speed is 200-300 rpm, the reaction temperature is 20-25° C., and the reaction time is 1-2 h.

7. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The purification method in step (7) is to use a dialysis bag for purification, the dialysis time is 24-48 hours, and the molecular weight of the dialysis bag is 8000-10000Da.

8. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The rotary evaporation temperature in step (8) is 50-60° C. and the time is 1-2 h.

9. The preparation method and application of a modified oat protein according to claim 1, characterized in that: The drying in step (9) is vacuum freeze drying, the drying temperature is -40°C, and the drying time is 12-24h.

10. The preparation method and application of modified oat protein according to claim 1, characterized in that: The crushing mesh size in step (10) is 80-100 mesh.

Images