Method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology

Abstract

The present invention relates to the technical field of plant protein modification and processing, and provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, wherein a certain mass of powdered pea protein isolate is weighed and packaged, and the packaged pea protein isolates are respectively placed in an acoustic resonance mixing container, and subjected to acoustic resonance treatment to obtain modified pea protein. The method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology of the present invention improves its solubility and emulsification properties by controlling the acoustic resonance treatment of pea protein isolate for different lengths, thereby obtaining a pea protein product that can meet the needs of food processing, so as to improve its application value in food and beverages.

Description

Technical Field

[0001] The invention relates to the technical field of plant protein modification and processing, and in particular to a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology. Background Art

[0002] As people continue to pursue healthy, green and safe eating habits, the choice of protein intake is increasingly tending towards low-fat, low-calorie plant proteins. Pea protein has attracted much attention due to its low allergenicity, non-GMO characteristics, high antioxidant, high nutritional value and sustainable source. However, the solubility of natural pea protein is not ideal, and its functional properties are not prominent enough, which affects its large-scale application in the food industry. Current studies have shown that efficient and appropriate modification of pea protein can enhance the solubility and emulsification properties of pea protein, thereby meeting the needs of the food industry and consumer expectations.

[0003] Resonant Acoustic Mixing (RAM), also known as acoustic resonance mixing technology, is a new hybrid technology that has emerged in recent years based on the coupling of macroscopic vibration mixing and microscopic acoustic field mixing. It uses the resonance of a mechanical vibration system to generate high-intensity vibrations, which can excite low-frequency (about 60Hz) and high-acceleration (0-100g, g=9.8m·s -2 ) Under the stimulation of acoustic waves, the purpose of uniform dispersion of materials is achieved, which has the advantages of good mixing uniformity, good material dispersion and high crushing efficiency, and is also economical, green and safe. At present, acoustic resonance technology has been widely used in chemical, energy, medicine and other fields, but its application in the food field needs further research. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies of the prior art and propose a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology. By controlling the acoustic resonance treatment of pea protein isolate for different lengths, its solubility and emulsification properties are improved, and a pea protein product that can meet the needs of food processing is obtained, thereby improving its application value in food and beverages.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] A method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology comprises the following steps:

[0007] Step 1: Weigh a certain amount of powdered pea protein isolate for packaging;

[0008] Step 2: The packaged pea protein isolates are placed in acoustic resonance mixing containers respectively, and subjected to acoustic resonance treatment to obtain modified pea protein.

[0009] The raw material pea protein isolate of the present invention is affected by its own structure, and has poor solubility and emulsification properties. By subjecting the pea protein isolate to acoustic resonance treatment, the pea protein isolate structure is induced to stretch, so as to adjust the spatial structure of the pea protein isolate and reduce the particle size, and effectively improve and optimize the solubility and emulsification properties of natural plant protein. Specifically, during the acoustic resonance treatment process: 1) the field shear force can enhance the macroscopic vibration and microscopic acoustic flow mixing coupling inside the protein molecule; 2) the protein interacts with the medium and moves rapidly, reducing the particle size; the protein structure is caused to stretch and expose more active groups, and the solubility is significantly improved; at the same time, the emulsification activity of the modified pea protein isolate is improved.

[0010] Furthermore, the packaging process of the pea protein isolate in step 1 is carried out at 20-25°C.

[0011] Furthermore, the acoustic resonance treatment process of the pea protein isolate in step 2 is specifically as follows:

[0012] Step 2-1: Place the packaged pea protein isolate into acoustic resonance mixing containers respectively;

[0013] Step 2-2: Add an appropriate amount of white pickaxe beads to the mixing container as a medium to assist in protein fragmentation;

[0014] Step 2-3: Set and adjust the operating parameters of the acoustic resonance instrument and process the sample;

[0015] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0016] Furthermore, the diameters of the white beads in step 2-2 are 3 mm and 5 mm respectively.

[0017] Furthermore, in step 2-3, the sample is processed at 15-25°C.

[0018] Furthermore, the operating parameters of the acoustic resonance instrument in step 2-3 are as follows: the processing frequency is 55-65 Hz, the processing amplitude is 30-40%, the processing acceleration is 65.000-75.000 g, and the processing time is within 30 min.

[0019] Furthermore, the processing time of the acoustic resonance instrument is preferably 20 minutes.

[0020] The beneficial effects of the method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology provided by the present invention are as follows:

[0021] The present invention processes pea protein isolate by acoustic resonance, realizes low-frequency, high-acceleration vertical vibration in the container under the condition of small input energy, generates a uniform shear force field, makes the protein move rapidly, and then reduces the aggregation degree and particle size of the protein, and achieves the effect of adjusting the structure of the protein; when not processed by acoustic resonance, the pea protein isolate structure is relatively aggregated, the solubility is poor at this time, and the average particle size of the protein is larger; at the same time, its emulsification activity is relatively low, and the stability of the emulsion prepared by the pea protein isolate is poor; the natural pea protein isolate is modified by acoustic resonance technology, which can effectively adjust the particle size and spatial structure of the protein, promote the protein structure to stretch and expose more active groups, and the solubility and emulsification activity of the pea protein isolate are also significantly improved. Among them, when the 20min acoustic resonance treatment is adopted, the solubility of the protein is the highest and the particle size is the smallest, and its emulsification activity is also the best. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention is a process and functional characteristic analysis flow chart of the method for improving the solubility and emulsification performance of pea protein isolate based on acoustic resonance technology;

[0023] Figure 2 This is a bar graph of the solubility of pea protein isolate after acoustic resonance treatment in Comparative Example 1 and Examples 1-4 of the present invention;

[0024] Figure 3 This is a bar graph of the average particle size of pea protein isolate after acoustic resonance treatment in Comparative Example 1 and Examples 1-4 of the present invention;

[0025] Figure 4 This is a bar graph of the emulsifying activity index of pea protein isolate after acoustic resonance treatment in Comparative Example 1 and Examples 1-4 of the present invention.

[0026] in, Figure 2-Figure 4 Different lowercase letters (ad) indicate significant differences (P<0.05). DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but is not intended to limit the protection scope of the present invention.

[0028] Unless otherwise specified, the raw materials used in the present invention can be purchased from the market or are commonly used in the art. Unless otherwise specified, the methods in the following embodiments are all conventional methods in the art.

[0029] like Figure 1 As shown, the present invention provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0030] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 20-25°C, and store it in a dry environment until processing.

[0031] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0032] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15-20 g, and the capacity of the sample tank is 500 mL.

[0033] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0034] Step 2-3: Start processing the sample in an environment of 15-25°C, set and adjust the operating parameters of the acoustic resonance instrument; wherein the acoustic resonance processing frequency is set to 55-65Hz, the processing amplitude is 30-40%, the processing acceleration is 65.000-75.000g, and the processing time is within 30min.

[0035] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0036] In addition to the above steps, the specific implementation also includes step 3: performing functional property analysis on the above modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0037] Comparative Example 1

[0038] Comparative Example 1 provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0039] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 25°C, and store it in a dry environment until processing.

[0040] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0041] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15 g, and the capacity of the sample tank is 500 mL.

[0042] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0043] Step 2-3: Start processing the sample in a 25°C environment, set and adjust the operating parameters of the acoustic resonance instrument; among which, the acoustic resonance processing frequency is set to 61.2 Hz, the amplitude is 35%, the acceleration is 70.000g, and the processing time is 0 min, which serves as a control group.

[0044] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0045] Step 3: Analyze the functional properties of the modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0046] Example 1

[0047] This embodiment 1 provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0048] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 25°C, and store it in a dry environment until processing.

[0049] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0050] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15 g, and the capacity of the sample tank is 500 mL.

[0051] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0052] Step 2-3: Start processing the sample in an environment of 25°C, set and adjust the operating parameters of the acoustic resonance instrument; wherein, the acoustic resonance processing frequency is set to 61.2 Hz, the amplitude is 35%, the acceleration is 70.000 g, and the processing time is 5 min.

[0053] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0054] Step 3: Analyze the functional properties of the modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0055] Example 2

[0056] This embodiment 2 provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0057] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 25°C, and store it in a dry environment until processing.

[0058] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0059] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15 g, and the capacity of the sample tank is 500 mL.

[0060] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0061] Step 2-3: Start processing the sample in an environment of 25°C, set and adjust the operating parameters of the acoustic resonance instrument; wherein, the acoustic resonance processing frequency is set to 61.2 Hz, the amplitude is 35%, the acceleration is 70.000 g, and the processing time is 10 min.

[0062] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0063] Step 3: Analyze the functional properties of the modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0064] Example 3

[0065] This embodiment 3 provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0066] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 25°C, and store it in a dry environment until processing.

[0067] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0068] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15 g, and the capacity of the sample tank is 500 mL.

[0069] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0070] Step 2-3: Start processing the sample in an environment of 25°C, set and adjust the operating parameters of the acoustic resonance instrument; wherein, the acoustic resonance processing frequency is set to 61.2 Hz, the amplitude is 35%, the acceleration is 70.000 g, and the processing time is 20 min.

[0071] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0072] Step 3: Analyze the functional properties of the modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0073] Example 4

[0074] This embodiment 4 provides a method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, comprising the following steps:

[0075] Step 1: Weigh and package the powdered pea protein isolate according to a certain mass at 25°C, and store it in a dry environment until processing.

[0076] Step 2: subjecting the packaged pea protein isolate to an acoustic resonance treatment, specifically comprising the following steps:

[0077] Step 2-1: Add the packaged pea protein isolate powder into stainless steel sample tanks respectively; wherein the mass of the protein sample added is 15 g, and the capacity of the sample tank is 500 mL.

[0078] Step 2-2: Add white beads of appropriate mass to the sample jar as a medium to assist in protein fragmentation; wherein the diameters of the beads are 3 mm and 5 mm respectively.

[0079] Step 2-3: Start processing the sample in an environment of 25°C, set and adjust the operating parameters of the acoustic resonance instrument; wherein, the acoustic resonance processing frequency is set to 61.2 Hz, the amplitude is 35%, the acceleration is 70.000 g, and the processing time is 30 min.

[0080] Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

[0081] Step 3: Analyze the functional properties of the modified pea protein, mainly including solubility, particle size, and emulsification activity analysis.

[0082] Experimental methods

[0083] Determination of solubility of pea protein isolate

[0084] A 2.5 mg / mL pea protein solution was prepared by diluting with phosphate buffer (10 mmol / L, pH 7.0). After centrifugation at 5000×g for 15 min, the soluble protein content in the supernatant was determined by the biuret method; the solubility of the protein was defined as follows:

[0085]

[0086] Determination of average particle size of pea protein isolate

[0087] A 2.5 mg / mL pea protein solution was prepared by diluting with phosphate buffer (10 mmol / L, pH 7.0), and the protein particle size was measured by a laser nanoparticle size distribution instrument. The parameters are as follows: the dispersant is 10 mmol / L phosphate buffer (pH 7.0); the refractive index of the dispersant is 1.3318; the number of repetitions is 3 times.

[0088] Determination of emulsifying properties of pea protein isolate

[0089] Preparation of pea protein isolate emulsion

[0090] A pea protein solution with a mass concentration of 10 mg / mL was prepared by diluting with phosphate buffer (10 mmol / L, pH 7.0), 10% (v / v) pure soybean oil was added and mixed, and after shearing at 13000 r / min for 2 min, 30 MPa high-pressure homogenization was cycled twice to obtain a pea protein isolate emulsion.

[0091] Determination of emulsifying activity of pea protein isolate

[0092] The homogenized emulsion was quickly transferred to a 100 mL beaker. 5 μL of the sample was taken from the bottom of the beaker at 0 and 10 min, 5 mL of 0.1% SDS was added, and the mixture was vortexed for 10 s. The SDS reagent was used as a blank and the absorbance at 500 nm was measured. The emulsification activity index (EAI) is defined as follows:

[0093]

[0094] in:

[0095] A500: absorbance value of the sample at 500nm;

[0096] DF: dilution factor;

[0097] c: initial protein concentration (g / mL);

[0098] Volume fraction of oil in the emulsion (v / v).

[0099] Experimental Results

[0100] Solubility is one of the important functional properties of protein, which can indirectly reflect the interaction between protein molecules and between protein and water molecules. Figure 2 As shown in the figure, compared with the pea protein isolate without acoustic resonance treatment, the solubility of the pea protein treated with acoustic resonance was significantly increased by more than 11.75% compared with the blank group protein; at the same time, the solubility of the protein first increased and then decreased with the extension of the acoustic resonance treatment time. During the acoustic resonance treatment, a uniform shear force field can be generated to enhance the macroscopic vibration and microscopic acoustic flow mixing coupling inside the protein molecules, promote the unfolding of the protein structure and the exposure of the active groups inside the protein, and thus improve the solubility; among them, the solubility of pea protein treated with acoustic resonance for 20 minutes is the largest, which is 71.8%, and the effect of improving the solubility of pea protein is the best at this time; on the contrary, the solubility of the protein treated with acoustic resonance for 30 minutes decreases to 57.91%.

[0101] like Figure 3 As shown in the figure, the average particle size of pea protein isolate can be effectively reduced by acoustic resonance treatment. Compared with pea protein isolate without acoustic resonance treatment, the average particle size of the protein treated with acoustic resonance decreased by 12.29% and more than 53.73%; at the same time, the average particle size of the protein first decreased and then increased with the extension of the acoustic resonance treatment time; among them, the best effect of 20min acoustic resonance treatment was 2138nm, which was compared with the control group. This shows that the shear force field generated by the acoustic resonance effect of the appropriate time and the friction between the dispersion medium (beads) can break up the protein aggregates, which is beneficial to strengthen the interaction between the protein and the water molecules when forming an aqueous solution; on the contrary, the average particle size of the protein treated with 30min acoustic resonance increased to 3034nm.

[0102] Emulsification is an important functional property of protein. Figure 4 As shown in the results, the emulsifying activity of pea protein isolate can be effectively enhanced by acoustic resonance treatment, and it first increases and then slightly decreases as the acoustic resonance treatment time increases; among them, the 20-min acoustic resonance treatment has the best effect, and its emulsifying activity is increased by more than 53.73% compared with the pea protein isolate without acoustic resonance treatment; on the contrary, the emulsifying activity of the protein treated with 30-min acoustic resonance is reduced by 12.29% compared with the 20-min treatment group. Choosing an appropriate acoustic resonance treatment time is helpful to improve the emulsifying properties of pea protein isolate.

[0103] The above experiments prove that the present invention significantly improves the solubility of pea protein isolate and reduces the average particle size of the protein by using the acoustic resonance technology. At the same time, the acoustic resonance treatment significantly improves the emulsification performance of the pea protein isolate and enhances the stability of the emulsion. Therefore, in the food and beverage industry, the application of acoustic resonance technology is expected to improve the solubility and processing performance of natural pea protein, and improve the quality of pea protein and the economic benefits of the enterprise.

[0104] Although the present invention has been described in detail in the embodiments through general explanations, specific implementation methods and experiments, modifications or improvements can still be made without departing from the core of the present invention, and all belong to the scope of protection required by the present invention.

Claims

1. A method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology, characterized in that: It consists of the following steps: Step 1: Weigh a certain amount of powdered pea protein isolate for packaging; Step 2: putting the packaged pea protein isolates into acoustic resonance mixing containers respectively, and subjecting them to acoustic resonance treatment to obtain modified pea protein; The acoustic resonance treatment process of pea protein isolate in step 2 is specifically as follows: Step 2-1: Place the packaged pea protein isolate into acoustic resonance mixing containers respectively; Step 2-2: Add an appropriate amount of white pickaxe beads to the mixing container as a medium to assist in protein fragmentation; Step 2-3: Set and adjust the operating parameters of the acoustic resonance instrument to process the sample. The operating parameters of the acoustic resonance instrument are as follows: the processing frequency is 55-65 Hz, the processing amplitude is 30-40%, the processing acceleration is 65.000-75.000 g, and the processing time is within 30 min; Step 2-4: After the acoustic resonance treatment is completed, the modified protein sample is quickly collected and sealed in a desiccator for storage.

2. The method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology according to claim 1, characterized in that: The packaging process of the pea protein isolate in step 1 is carried out at 20-25°C.

3. The method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology according to claim 2, characterized in that: The diameters of the white beads in step 2-2 are 3 mm and 5 mm respectively.

4. The method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology according to claim 2, characterized in that: In the step 2-3, the sample is treated at 15-25°C.

5. The method for improving the solubility and emulsification properties of pea protein isolate based on acoustic resonance technology according to claim 2, characterized in that: The processing time of the acoustic resonance instrument is preferably 20 min.

Images