Preparation method for improving structure and sensitization of whey protein concentrate through ultrasonic treatment

Abstract

The invention belongs to the technical field of protein modification, and relates to a preparation method for improving the structure and sensitization of whey protein concentrate through ultrasonic treatment. The whey protein concentrate is used as a raw material, and ultrasonic treatment is performed on the whey protein concentrate under the conditions of certain ultrasonic time and ultrasonic power. After ultrasonic treatment, freeze drying is performed to obtain a modified whey protein product. By adopting the method, the novel whey protein functional base material with good functional characteristics can be directly prepared, and the application field of the whey protein in the food industry is expanded.

Description

Technical Field

[0001] The invention belongs to the technical field of protein modification, and relates to a preparation method for improving the structure and allergenicity of whey concentrated protein by ultrasonic treatment. Background Art

[0002] Whey protein concentrate (WPC) is a whey protein product with a protein content of 35-85%. Whey protein is the main solid component in whey, a by-product of cheese production. It has high nutritional value, is an important raw material for preparing milk powder, and is widely used in processed foods. Whey protein contains β-lactoglobulin (β-LG), α-lactalbumin (α-LA), bovine serum albumin and other active ingredients. Among them, β-LG and α-LA are present in higher content in WPC and are also the main allergens of cow milk allergy. Therefore, it is very necessary to study the improvement of the structure of whey protein concentrate and the reduction of its allergenicity, and to affect the allergenicity through structural changes.

[0003] People are very interested in using protein modification technology to reduce the allergenicity of whey protein, because different processing technologies have different effects on the structure of whey concentrate, and the modification of the whey protein structure affects its allergenicity. Among them, the degree of change in the allergenicity of whey protein depends on the processing method, degree, processing time, etc. Therefore, it is very important to find a preparation method to improve the structure and allergenicity of whey protein, which can help people more fully understand the structural characteristics of proteins and provide a reference for the subsequent preparation of whey protein related products.

[0004] At present, the commonly used method for improving the structure and sensitization of whey protein mainly includes thermal processing modification, hydrolysis modification, microbial fermentation modification, irradiation modification, ultraviolet modification, ultrasonic modification and high pressure modification. These methods all have the effect of changing the structure and sensitization of whey protein, but each technology itself also has obvious shortcomings. For example, thermal processing to a certain temperature can destroy the protein structure, making it lose its original functional characteristics. Therefore, ultrasonic treatment, as a non-thermal processing treatment method, has the characteristics of strong penetration, good directionality, large energy, etc., and has great potential in protein modification and new product development. Therefore, the present invention uses whey protein concentrate as raw material, utilizes ultrasonic treatment technology to carry out physical modification on it, in order to obtain high-quality, safe, low-sensitization functional base material of whey protein. Summary of the invention

[0005] The purpose of the present invention is to provide a reference for improving the production and processing utilization rate of whey protein and developing new low-allergenic dairy products by analyzing the relationship between the changes in the spatial structure of whey protein concentrate and its allergenicity.

[0006] The purpose of the present invention is achieved by implementing the following technical solutions:

[0007] A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment of the present invention comprises the following steps:

[0008] (1) Preparation of whey protein concentrate: Dissolve whey protein concentrate in deionized water to prepare a solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution.

[0009] (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic process, ice cubes are placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power is 0-200 W, and the ultrasonic treatment time is 0-20 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution is obtained.

[0010] In the present invention, preferably, the ultrasonic treatment time in step (2) is 15 minutes.

[0011] In the present invention, preferably, the ultrasonic treatment power in step (2) is 150W.

[0012] The present invention is different from the prior art in that the present invention has achieved the following technical results:

[0013] Ultrasonic wave can change the microstructure, secondary and tertiary structures of whey protein concentrate by modifying protein, improve the content of total sulfhydryl, surface sulfhydryl and surface hydrophobicity of protein, mean that the surface structure of protein can be changed, the structure can be unfolded, and the sensitizing antigen content of protein can also be reduced, but the influence of ultrasonic treatment on the hydrolysis degree and molecular weight of whey protein concentrate is small. As a non-thermal processing method, ultrasonic treatment protein is more mild in condition, while thermal processing method can change the protein structure and denature it, destroying the integrity of its protein, and being applied to whey protein can have adverse effects on its nutrition, mouthfeel, etc. The whey protein obtained by the present invention has excellent characteristics and can be widely used as functional base material in food industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 These are scanning electron microscope images of Examples 1-4 of the present invention under different ultrasonic treatments.

[0015] Figure 2 Circular dichroism spectra under different ultrasonic treatments in Examples 1-4 of the present invention.

[0016] Figure 3 The intrinsic fluorescence spectra under different ultrasonic treatments in Examples 1-4 of the present invention.

[0017] Figure 4The hydrophobicity of the surface under different ultrasonic treatments in Examples 1-4 of the present invention.

[0018] Figure 5 It is the thiol content under different ultrasonic treatments in Examples 1-4 of the present invention.

[0019] Figure 6 It is the degree of hydrolysis under different ultrasonic treatments in Examples 1-4 of the present invention.

[0020] Figure 7 The gel electrophoresis diagrams are shown in Examples 1-4 of the present invention under different ultrasonic treatments.

[0021] Figure 8 It is the antigen inhibition rate of whey protein concentrate under different ultrasonic treatments in Examples 1-4 of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, the embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of protection of the present invention.

[0023] Example 1

[0024] A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment, comprising the following steps:

[0025] (1) Preparation of whey protein concentrate: Dissolve whey protein concentrate in deionized water to prepare a solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution.

[0026] (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic process, ice cubes were placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power was 150 W, and the ultrasonic treatment time was 10 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution was obtained.

[0027] Example 2

[0028] A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment, comprising the following steps:

[0029] (1) Preparation of whey protein concentrate: Dissolve whey protein concentrate in deionized water to prepare a solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution.

[0030] (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic process, ice cubes were placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power was 150 W, and the ultrasonic treatment time was 15 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution was obtained.

[0031] Example 3

[0032] A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment, comprising the following steps:

[0033] (1) Preparation of whey protein concentrate: Dissolve whey protein concentrate in deionized water to prepare a solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution.

[0034] (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic process, ice cubes were placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power was 150 W, and the ultrasonic treatment time was 20 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution was obtained.

[0035] Example 4

[0036] A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment, comprising the following steps:

[0037] (1) Preparation of whey protein concentrate: Dissolve whey protein concentrate in deionized water to prepare a solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution.

[0038] (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic process, ice cubes were placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power was 200 W, and the ultrasonic treatment time was 15 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution was obtained.

[0039] The present invention illustrates the preparation method of improving the structure and sensitization of whey protein concentrate by ultrasonic treatment provided by the present invention through the above-mentioned embodiments, but the above-mentioned is only the best embodiment of the present invention. It should be pointed out that the above embodiments are only used to illustrate the present invention, and are not used to limit the protection scope of the present invention. For those of ordinary skill in the art, without departing from the principle of the present invention, some improvements can also be made, and these improvements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method for improving the structure and allergenicity of whey protein concentrate by ultrasonic treatment, characterized in that The following steps are involved: (1) Preparation of whey protein concentrate solution: Dissolve whey protein concentrate in deionized water to prepare a whey protein concentrate solution with a concentration of 50 mg / ml, place it on a magnetic stirrer and stir for 2 h to completely dissolve the whey protein concentrate to obtain a whey protein concentrate solution; (2) Ultrasonic treatment of whey protein concentrate: During the ultrasonic treatment, ice cubes were placed to keep the temperature of the whey protein concentrate solution constant, the ultrasonic treatment power was 0-200 W, and the ultrasonic treatment time was 0-20 min. After the ultrasonic treatment, an ultrasonically treated whey protein concentrate solution was obtained.

2. The method for preparing whey protein concentrate by ultrasonic treatment to improve its structure and sensitization according to claim 1, characterized in that: The concentration of whey protein concentrate in step (1) is 50 mg / ml.

3. The method for preparing whey protein concentrate by ultrasonic treatment to improve its structure and sensitization according to claim 1, characterized in that: The ultrasonic treatment power in step (2) is 150W.

4. The method for preparing whey protein concentrate by ultrasonic treatment to improve its structure and sensitization according to claim 1, characterized in that: The ultrasonic treatment time in step (2) is 15 minutes.

5. The detection method according to claim 1, characterized in that: The detection method is suitable for a preparation method for improving the structure and allergenicity of whey protein concentrate.

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