Method for efficiently extracting grease and protein in peanuts by high static pressure and aqueous enzymatic method
Through high static pressure synergistic aqueous enzyme method, oil and protein in peanuts can be efficiently extracted, solving the problems of low clear oil yield and poor protein integrity in peanut oil processing, and achieving efficient and economical separation of peanut oil and protein.
Patent Information
- Application Number
- CN202510938359.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-08
- Publication Date
- 2025-09-26
AI Technical Summary
Existing technologies make it difficult to simultaneously ensure the peanut oil extraction rate and protein integrity, resulting in low clear oil yield and reduced protein functionality during peanut oil processing.
The high static pressure synergistic aqueous enzyme method is adopted to destroy the peanut cell wall through high static pressure pretreatment, and combine enzymatic hydrolysis and centrifugation steps to achieve efficient separation of oil and protein.
It improves the extraction rate of peanut oil and protein, maintains the integrity of protein, reduces production costs and energy consumption, and increases industrial economic benefits.
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Abstract
Description
Technical Field
[0001] The invention relates to a method for efficiently extracting oil and protein from peanuts using a high static pressure coordinated aqueous enzyme method, and belongs to the technical field of peanut oil processing. Background Art
[0002] Traditional oil extraction is achieved through physical mechanical pressing combined with wet heat treatment to destroy the cell walls, thereby releasing oil molecules and collecting protein substances. However, the protein is severely denatured during the pressing process, which restricts its further high-value utilization.
[0003] The aqueous enzymatic oil production process is based on the physical crushing of peanut kernels. Enzymes that can break down the cell walls, lipoproteins, and lipopolysaccharides in the oilseed cells are added to disrupt the tissue structure, thereby fully releasing the oil and protein. The differences in their hydrophilic and lipophilic properties are utilized to separate the oil and protein with the help of mechanical means such as centrifugation. The degree of cell wall damage during the aqueous enzymatic oil production process directly affects the release of oil and protein. Peanut tissue is usually broken up mechanically, and then enzymes are added to degrade the cell walls to better release oil and protein, but it is difficult to simultaneously guarantee the clear oil yield and protein integrity. First, the type of enzyme selected affects the extent of the enzyme's effect on the cell wall and other components, thereby affecting the clear oil yield and protein integrity. For example, the introduction of proteases can degrade protein and lipoprotein components, resulting in the decomposition of proteins into small peptides. This increases the clear oil yield, but affects the integrity and functionality of the protein and increases the difficulty of demulsification and separation of the emulsified oil. Cell wall hydrolases can ensure protein integrity, but there is a problem of low clear oil yield. Secondly, the mechanical methods used in the process can also affect the clear oil yield and protein integrity. Gentle mechanical methods fail to completely disrupt the cell walls, resulting in a low clear oil yield. Violent mechanical methods, while sufficient cell wall disruption and a high breakage rate can lead to a high clear oil yield, can also lead to the inactivation of macromolecules and protein damage. However, ensuring both clear oil yield and protein integrity can improve the comprehensive utilization of peanut oil and protein, resulting in high-quality oil and protein products, effectively enhancing nutritional value and safety, meeting market demand, and increasing economic benefits.
[0004] Therefore, the key to high-value processing of peanut oil is how to break through the constraints of the cell wall on peanut oil and protein, achieve efficient and complete separation of oil and protein in peanuts, and thus efficiently extract oil and protein from peanuts while ensuring the clear oil yield and protein integrity. Summary of the Invention
[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a method for efficiently extracting oil and protein from peanuts by high static pressure and aqueous enzymatic method, which can efficiently extract oil and protein from peanuts while ensuring the oil extraction rate and protein integrity.
[0006] In order to solve the above technical problems, the technical solution provided by the present invention is: A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: Mix peanut kernel powder with water and stir ultrasonically at room temperature for 30-60 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed liquid is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium for high static pressure treatment to obtain a solution after high static pressure treatment; (5) Enzymatic hydrolysis: Add mixed enzymes to the solution after high static pressure treatment to carry out enzymatic hydrolysis reaction, then place it in boiling water to inactivate the enzyme for 10 min, and cool it to room temperature to obtain enzymatic hydrolyzate; (6) Alkali extraction: adjust the pH of the enzymatic hydrolyzate to 9.0-9.5 with a 2 mol / L sodium hydroxide solution and perform alkaline extraction for 20-50 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: After microwave treatment of the high oil content emulsion, centrifuge at 4000-8000 r / min for 15-30 min to obtain oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 min, and centrifuge at 4000-8000 r / min for 15-30 min to obtain protein.
[0007] Furthermore, in step (3), the mass ratio of the peanut kernel powder to water is 1:5.
[0008] Furthermore, in step (3), the power of the ultrasound is 100-500W.
[0009] Furthermore, in step (4), the pressure of the high static pressure treatment is 200-500 MPa, and the time of the high static pressure treatment is 20-60 min. The mixed solution is subjected to high static pressure treatment and maintained for a certain period of time to allow the pressure inside and outside the cell to reach equilibrium, and then the pressure is released instantly. Due to the sudden increase in the osmotic pressure difference between the inside and outside of the cell, the cell wall components themselves and the physical combination with the protein and oil components can be fully destroyed, and the structure of the cell membrane changes, and the channels inside and outside the cell wall are opened, so that the effective ingredients such as oil in the cell can pass through the cell membrane and transfer to the extract outside the cell, which is conducive to the outflow of protein and oil molecules after the enzymatic hydrolysis reaction. The present invention breaks through the constraints of the cell wall on peanut oil and protein, realizes the efficient and complete separation of oil and protein in peanuts, improves the clear oil yield, and can also shorten the subsequent enzymatic hydrolysis time and improve industrial efficiency.
[0010] Furthermore, in step (4), the pressure transmission medium is water.
[0011] Furthermore, in step (5), the enzyme mixture is a mixture of any two or more of pectinase, cellulase, or hemicellulase. The enzyme mixture can degrade anti-nutritional factors such as pectin and cellulose in plant cell walls, thereby releasing components such as lipids and proteins.
[0012] Furthermore, in step (5), the amount of the enzyme mixture added is 2-5% of the mass of the solution after high static pressure treatment. Adding an appropriate amount of the enzyme mixture is beneficial to the enzymatic hydrolysis reaction, because if the amount of enzyme added is insufficient, the enzymatic hydrolysis reaction is incomplete and the release of oil and protein is incomplete; if the amount of enzyme added is too high, a large amount of enzyme will adhere to each other, reducing the mass transfer efficiency between the enzyme and the substrate, thereby reducing the reaction efficiency and inhibiting the degradation of the peanut cell wall and the release of oil and protein.
[0013] Furthermore, in step (5), the temperature of the enzymatic hydrolysis reaction is 40-60° C., and the time of the enzymatic hydrolysis reaction is 2-4 h.
[0014] Furthermore, in step (7), the centrifugal speed is 4000-8000 r / min, and the centrifugal time is 15-30 min.
[0015] Furthermore, in step (8), the power of the microwave treatment is 500-800 W, and the time of the microwave treatment is 40-80 s.
[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention subjects the peanut powder mixture to high static pressure pretreatment. Due to the sudden change in the osmotic pressure difference between the inside and outside of the cells, the physical combination of the cell wall components and the protein and oil components is fully destroyed, which is beneficial to the dissolution of protein and oil in the peanut kernel and improves the extraction rate of oil and protein in the peanut.
[0017] (2) The present invention pre-treats the peanut mixture under high static pressure, then performs enzymatic hydrolysis and alkaline protein extraction to obtain a high-concentration oil-containing emulsion, which is then subjected to microwave physical demulsification to obtain oil. This can not only maintain the integrity of the protein to the maximum extent, but also further improve the oil yield, and reduce the amount of enzyme used and the enzymatic hydrolysis time, which is conducive to reducing costs and improving efficiency.
[0018] (3) The present invention adopts high static pressure pretreatment at room temperature to avoid oil oxidation caused by high temperature, reduce energy consumption, lower production costs, and obtain complete protein at the same time as oil, with a high comprehensive utilization rate, thereby improving industrial economic benefits. DETAILED DESCRIPTION
[0019] Example 1 A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: peanut kernel powder and water were mixed at a mass ratio of 1:5, and ultrasonically stirred at room temperature for 45 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed solution is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium. The high static pressure treatment is carried out at a pressure of 200 MPa for 20 minutes to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add a mixed enzyme to the solution treated with high static pressure, wherein the mixed enzyme is a mixture of pectinase and cellulase, and perform enzymatic hydrolysis at 50°C for 3 hours, then place the solution in boiling water for 10 minutes to inactivate the enzyme, and cool it to room temperature to obtain an enzymatic hydrolyzate; the amount of the mixed enzyme added is 3% of the mass of the solution treated with high static pressure; (6) Alkali extraction: The enzymatic hydrolyzate was adjusted to pH 9.0-9.5 with a 2 mol / L sodium hydroxide solution and subjected to alkaline extraction for 30 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract at 6000 r / min for 20 min to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: The high-oil emulsion was microwave-treated at 600 W for 60 seconds and then centrifuged at 6000 r / min for 30 minutes to obtain the oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 min, and centrifuge at 6000 r / min for 15 min to obtain the protein.
[0020] Example 2 A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: peanut kernel powder and water were mixed at a mass ratio of 1:5, and ultrasonically stirred at room temperature for 30 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed liquid is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium. The high static pressure treatment is carried out at a pressure of 200 MPa for 30 minutes to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add a mixed enzyme to the solution treated with high static pressure. The mixed enzyme is a mixture of pectinase, cellulase, and hemicellulase. The enzymatic hydrolysis reaction is carried out at 50°C for 3 hours. Then, the solution is placed in boiling water for 10 minutes to inactivate the enzymes. The solution is cooled to room temperature to obtain an enzymatic hydrolyzate. The amount of the mixed enzyme added is 4% of the mass of the solution treated with high static pressure. (6) Alkali extraction: The enzymatic hydrolyzate was adjusted to pH 9.0-9.5 with a 2 mol / L sodium hydroxide solution and subjected to alkaline extraction for 40 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract at 6000 r / min for 20 min to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: The high-oil emulsion was microwaved at 700 W for 50 s and then centrifuged at 5000 r / min for 25 min to obtain the oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 minutes, and centrifuge at 8000 r / min for 15 minutes to obtain protein.
[0021] Example 3 A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: peanut kernel powder and water were mixed at a mass ratio of 1:5, and ultrasonically stirred at room temperature for 40 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed solution is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium. The high static pressure treatment is carried out at a pressure of 300 MPa for 30 minutes to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add a mixed enzyme to the solution treated with high static pressure. The mixed enzyme is a mixture of pectinase, cellulase, and hemicellulase. The enzymatic hydrolysis reaction is carried out at 50°C for 3 hours. Then, the solution is placed in boiling water for 10 minutes to inactivate the enzymes. The solution is cooled to room temperature to obtain an enzymatic hydrolyzate. The amount of the mixed enzyme added is 4% of the mass of the solution treated with high static pressure. (6) Alkali extraction: The enzymatic hydrolyzate was adjusted to pH 9.0-9.5 with a 2 mol / L sodium hydroxide solution and subjected to alkaline extraction for 30 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract at 6000 r / min for 20 min to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: The high-oil emulsion was microwave-treated at 600 W for 70 s and then centrifuged at 6000 r / min for 30 min to obtain the oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 min, and centrifuge at 8000 r / min for 15 min to obtain protein.
[0022] Example 4 A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: peanut kernel powder and water were mixed at a mass ratio of 1:5, and ultrasonically stirred at room temperature for 50 min to obtain a mixed solution; (4) High static pressure pretreatment: The mixed solution is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium. The high static pressure treatment is carried out at a pressure of 400 MPa for 40 minutes to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add a mixed enzyme to the solution treated with high static pressure. The mixed enzyme is a mixture of cellulase and hemicellulase. The enzymatic hydrolysis reaction is carried out at 50°C for 3 hours. Then, the solution is placed in boiling water for 10 minutes to inactivate the enzyme. The solution is cooled to room temperature to obtain an enzymatic hydrolyzate. The amount of the mixed enzyme added is 4% of the mass of the solution treated with high static pressure. (6) Alkali extraction: The enzymatic hydrolyzate was adjusted to pH 9.0-9.5 with a 2 mol / L sodium hydroxide solution and subjected to alkaline extraction for 40 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract at 6000 r / min for 25 min to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: The high-oil emulsion was microwave-treated at 700 W for 60 s and then centrifuged at 6000 r / min for 20 min to obtain the oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 min, and centrifuge at 6000 r / min for 25 min to obtain protein.
[0023] Example 5 A method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method, comprising the following steps: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: peanut kernel powder and water were mixed at a mass ratio of 1:5, and ultrasonically stirred at room temperature for 60 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed solution is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium. The high static pressure treatment is carried out at a pressure of 500 MPa for 60 minutes to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add a mixed enzyme to the solution treated with high static pressure. The mixed enzyme is a mixture of pectinase and hemicellulase. The enzymatic hydrolysis reaction is carried out at 60°C for 2 hours. Then, the solution is placed in boiling water for 10 minutes to inactivate the enzyme. The solution is cooled to room temperature to obtain an enzymatic hydrolyzate. The amount of the mixed enzyme added is 2% of the mass of the solution treated with high static pressure. (6) Alkali extraction: The enzymatic hydrolyzate was adjusted to pH 9.0-9.5 with a 2 mol / L sodium hydroxide solution and subjected to alkaline extraction for 40 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract at 5000 r / min for 20 min to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: The high-oil emulsion was microwave-treated at 600 W for 50 s and then centrifuged at 5000 r / min for 20 min to obtain the oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 min, and centrifuge at 5000 r / min for 20 min to obtain protein.
[0024] Comparative Example 1 The method is the same as that of Example 3, except that step (4) is not performed.
[0025] Comparative Example 2 The method is the same as that of Example 3, except that step (4) is not performed, and the amount of the mixed enzyme added in the enzymatic hydrolysis of step (5) is 8% of the mass of the solution treated with high static pressure.
[0026] Comparative Example 3 The method is the same as that of Example 3, except that step (4) is not performed, and the enzymatic hydrolysis time in step (5) is 6 h.
[0027] Experimental Example 1 The extraction rates of oil and protein in Examples 1-5 were tested, and the test results are listed in Table 1.
[0028] The protein content was determined by the Kjeldahl method, and the protein extraction rate was calculated according to the following formula; the oil was placed in a vacuum drying oven and dried at 45-50°C for 10 hours, and the oil extraction rate was calculated according to the following formula; Protein extraction rate = ; Oil extraction rate = ; Among them, the oil content of peanuts is determined in accordance with "GB 5009.6-2016 National Food Safety Standard Determination of Fat in Foods".
[0029] Table 1. Extraction rate of oil and protein As shown in Table 1, the oil extraction rates for Examples 1-5 were all above 75.37%, and the protein extraction rates were all above 74.66%. This demonstrates that the present method, through the synergistic combination of high-static-pressure pretreatment and aqueous enzymatic method, can efficiently extract oil and protein from peanuts. This is because the present method pressurizes the peanut powder and water mixture to above 200 MPa, maintains the pressure for a certain period of time to allow the intracellular and extracellular fluid pressures to reach equilibrium, and then instantly releases the pressure. This suddenly increases the intracellular and extracellular osmotic pressure difference, opening channels inside and outside the cell wall, which facilitates the outflow of protein and oil molecules after the next enzymatic hydrolysis reaction.
[0030] Experimental Example 2 The extraction rates of oil and protein in Example 3 and Comparative Examples 1-3 were tested, and the test results are listed in Table 2.
[0031] Table 2. Extraction rate of oil and protein As can be seen from Table 2, in Comparative Example 1, no high static pressure pretreatment was performed, and the extraction rate of oil and fat was 69.02%, and the extraction rate of protein was 72.38%. This indicates that in the absence of high static pressure pretreatment, lower enzyme concentrations and shorter enzymatic hydrolysis times cannot fully degrade the cell wall, proving that high static pressure pretreatment has a significant promoting effect on the aqueous enzymatic extraction of oil and protein. Comparative Example 2 increases the amount of mixed enzyme added on the basis of Comparative Example 1, and Comparative Example 3 increases the enzymatic hydrolysis time on the basis of Comparative Example 1. The extraction rates of oil and protein are improved, but both are lower than those of Example 3, indicating that increasing the amount of enzyme and extending the enzymatic hydrolysis time can promote the degradation of cell walls and improve the extraction rates of oil and protein, but the effect is still worse than that of Example 3. It can be seen that the process of the present invention adopts high static pressure pretreatment to facilitate the outflow of protein and oil molecules after the enzymatic hydrolysis reaction, which can not only improve the extraction efficiency of oil and fat, maintain the integrity of protein, but also save the amount of enzyme and enzymatic hydrolysis time, and reduce production costs.
[0032] Experimental Example 3 To investigate the effect of high-pressure pretreatment on the extraction yields of oil and protein, the process steps were the same as in Example 3, except that the high-pressure pretreatment pressures were set to 100 MPa, 200 MPa, 300 MPa, 400 MPa, 500 MPa, and 600 MPa, respectively. The extraction yields of oil and protein were measured, and the results are listed in Table 3.
[0033] Table 3. Extraction rate of oil and protein As shown in Table 3, as the pressure of the high static pressure pretreatment increases, the oil and protein extraction rates first increase and then decrease. This is because at low pressure, the cell structure is destroyed, promoting oil release, and the protein does not undergo significant denaturation, leaving the protein relatively intact. However, when the pressure is too high, the protein will be excessively denatured, encapsulating the oil to form a gel, hindering the extraction of the oil, resulting in a low clear oil yield and low protein integrity. Moreover, excessive pressure will also increase production costs. Therefore, the present invention selects a high static pressure pretreatment pressure of 200-500 MPa.
[0034] Experimental Example 4 To investigate the effect of high-pressure pretreatment time on the extraction yield of oil and protein, the process steps were the same as in Example 3, with the high-pressure pretreatment time set at 10 min, 20 min, 30 min, 40 min, 50 min, 60 min, and 70 min, respectively. The extraction yields of oil and protein were measured, and the results are listed in Table 4.
[0035] Table 4. Extraction rate of oil and protein As can be seen from Table 4, as the high static pressure pretreatment time is extended, the oil and protein extraction rates first increase and then decrease. This is because the cell structure is destroyed in a relatively short period of time. As time goes on, the cell wall is destroyed more and more thoroughly, promoting the release of oil and protein extraction. However, excessive treatment time can lead to severe protein denaturation. The denatured protein encapsulates some oil and remains in the solid phase, hindering the dissolution of oil and protein, significantly reducing the peanut oil yield and peanut protein yield, and the protein integrity is low. Moreover, excessive treatment time can also increase production costs. Therefore, the present invention selects a high static pressure pretreatment time of 20-60 minutes.
Claims
1. A method for efficiently extracting oil and protein from peanuts using a high-static-pressure, aqueous-enzymatic method, characterized by: The following steps are involved: (1) Raw material screening: remove impurities and moldy peanuts from peanuts to obtain screened peanut kernels; (2) Crushing: crush the screened peanut kernels with a high-speed grinder for 30 seconds, and pass through a 400-mesh sieve to obtain peanut kernel powder; (3) Material-liquid mixing: Mix peanut kernel powder with water and stir ultrasonically at room temperature for 30-60 min to obtain a mixed liquid; (4) High static pressure pretreatment: The mixed liquid is sealed in a polyethylene bag, placed in the inner cavity of the pressure vessel of the high static pressure equipment, and immersed in the pressure transmission medium for high static pressure treatment to obtain a high static pressure treated solution; (5) Enzymatic hydrolysis: Add mixed enzymes to the solution treated with high static pressure to carry out enzymatic hydrolysis reaction, then place it in boiling water to inactivate the enzyme for 10 minutes, and cool it to room temperature to obtain enzymatic hydrolyzate; (6) Alkali extraction: adjust the pH of the enzymatic hydrolyzate to 9.0-9.5 with a 2 mol / L sodium hydroxide solution and perform alkaline extraction for 20-50 min to obtain an alkaline extract; (7) Centrifugation: Centrifuge the alkaline extract to obtain a high-oil emulsion, aqueous phase 1, and residue; (8) Microwave demulsification: After microwave treatment of the high oil content emulsion, centrifuge at 4000-8000 r / min for 15-30 min to obtain oil and water phase 2; (9) Acid precipitation: Combine aqueous phase 1 and aqueous phase 2, adjust the pH to 4.0-5.0 with 2 mol / L hydrochloric acid solution, acid precipitate for 10 minutes, and centrifuge at 4000-8000 r / min for 15-30 minutes to obtain protein.
2. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 1, characterized in that: In step (3), the mass ratio of the peanut kernel powder to water is 1:
5.
3. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 2, characterized in that: In step (4), the pressure of the high static pressure treatment is 200-500 MPa, and the time of the high static pressure treatment is 20-60 min.
4. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 3, characterized in that: In step (5), the amount of the mixed enzyme added is 2-5% of the mass of the solution treated with high static pressure.
5. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 4, characterized in that: In step (5), the temperature of the enzymatic hydrolysis reaction is 40-60° C., and the time of the enzymatic hydrolysis reaction is 2-4 h.
6. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 5, characterized in that: In step (7), the centrifugal speed is 4000-8000 r / min, and the centrifugal time is 15-30 min.
7. The method for efficiently extracting oil and protein from peanuts by high static pressure synergistic aqueous enzymatic method according to claim 6, characterized in that: In step (8), the power of the microwave treatment is 500-800 W, and the time of the microwave treatment is 40-80 s.