Walnut peptide as well as preparation method and application thereof
The preparation of walnut peptides through stacking, fumigation, bacterial infusion, fermentation and enzymatic decomposition has solved the problem of failing to effectively utilize walnut resources in the prior art, and achieved a low-cost and improved memory effect.
Patent Information
- Application Number
- CN202411381854.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2024-12-10
AI Technical Summary
At present, there is a lack of mature deep processing methods for walnut kernels, and it has failed to effectively use its resources to develop products that can nourish the brain and strengthen the brain, which cannot effectively improve the problem of cognitive function decline in the elderly.
Walnut peptides are prepared by stacking, fumigation, bacterial infusion, fermentation, enzymatic decomposition, filtration and other steps. The walnut peptides in walnut meal are extracted by fermentation, and the treatment is carried out using steam and microbial enzymes. Combined with the addition of bentonite and diatomaceous earth, walnut peptides are realized. Extraction and drying.
It effectively extracts walnut peptides, which are cheap and have a certain memory-improving effect, and provides a product that improves memory.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of food engineering, and specifically relates to a walnut peptide and a preparation method and application thereof. Background Art
[0002] As the global population ages, my country is also facing dramatic changes in its population structure. By the end of 2023, my country's population aged 60 and above will reach 297 million, accounting for 21.1% of the national population, and is expected to increase to 37.2% by 2050. The public health challenges brought about by an aging population are becoming increasingly severe, especially the decline in cognitive function among the elderly, which has caused huge emotional burdens and economic pressures on families and society. Studies have shown that dietary intervention can effectively protect cognitive function or delay its decline.
[0003] Walnut kernels are rich in nutrients such as 40%-65% oil, 14%-17% protein, and 5.8% vitamins. They have multiple functions such as strengthening the stomach, nourishing blood, moistening the lungs, benefiting the kidneys, and nourishing the brain. According to the Compendium of Materia Medica, walnut kernels can nourish qi and blood, moisten dryness and resolve phlegm, warm the lungs and moisten the intestines, and are sweet and mild in nature. Kaibao Mucao says that walnut kernels "make people strong, moisturize the skin, and blacken the hair and beard". Walnut meal, a byproduct of walnut kernel oil extraction, contains rich walnut protein and can be processed in depth to turn waste into treasure and develop products that can nourish the brain. However, there is no mature product processing method yet. Summary of the invention
[0004] In order to solve the above problems, the present invention provides a method for preparing walnut peptide, comprising the following steps:
[0005] (1) Stacking: watering the walnut raw materials, stirring and stacking;
[0006] (2) Fumigation: passing steam to fumigate the raw materials;
[0007] (3) Inoculation: Prepare a fermentation agent using Eurotium cristatum and / or Aspergillus oryzae and spray it onto the surface of the fumigated raw materials;
[0008] (4) Fermentation: The inoculated raw materials are placed in an environment with a temperature of 25° C. to 35° C. and a relative humidity of 50% to 90% for fermentation for 2 to 7 days;
[0009] (5) Enzymatic hydrolysis: add water to the fermented raw materials at a ratio of 1:3-20, heat to 90°C, and heat for 30 minutes; then adjust the temperature to 45-60°C, adjust the pH to 4-7, add 0.1%-3% cellulase for enzymatic hydrolysis for 2-6 hours; adjust the pH to 5-8; first add 0.3%-3% alkaline protease for enzymatic hydrolysis for 2-6 hours, then adjust the pH to 5-7, add flavor protease and kiwi protease for enzymatic hydrolysis for 2-6 hours, the addition amount is 0.1%-3%, and the ratio is 1:1-5; heat to 90°C, inactivate the enzyme for 30 minutes to obtain the enzymatic solution;
[0010] (6) Filtration: Add bentonite and diatomaceous earth to the enzymatic hydrolyzate, decolorize for 20-90 minutes, and filter; the filtrate after decolorization and filtration is filtered using a 7KD ultrafiltration membrane, and then filtered through nanofiltration and spray-dried to obtain walnut peptide.
[0011] Furthermore, the walnut raw material in step (1) is walnut meal or walnut protein.
[0012] Furthermore, the walnut raw material in step (1) is walnut meal or walnut protein made from wild walnuts from Changbai Mountain.
[0013] Furthermore, in step (1), the moisture content of the walnut raw material is 10% to 40%, and the stacking temperature is 10° C. to 60° C.
[0014] Furthermore, the fumigation in step (2) is performed by introducing 0.10-0.2Mpa steam for 2-10 minutes.
[0015] Furthermore, the fumigation in step (2) is performed by introducing 0.10-0.12Mpa steam for 3-5 minutes.
[0016] Furthermore, in step (5), the ratio of enzymatic hydrolysis to water is 1:5-10, the pH of cellulase hydrolysis is 5-7, and the enzymatic hydrolysis time is 4-6 hours; the pH of alkaline protease is 6-8, the addition ratio is 0.5%-1.5%, and the enzymatic hydrolysis pH is 6-8; the addition amount of flavor protease and homemade kiwi protease is 0.6%-2%, and the ratio is 1:1-3.
[0017] Furthermore, in step (6), the amount of bentonite and diatomite added is 1%-10% of the total mass, and the mass ratio of bentonite to diatomite is 1:1-6.
[0018] Furthermore, in step (6), the amount of bentonite and diatomite added is 3%-7% of the total mass, and the mass ratio of bentonite to diatomite is 1:2-4.
[0019] The present invention also provides the use of the walnut peptide prepared by the preparation method in preparing a product for improving memory.
[0020] The present invention has the following beneficial effects:
[0021] The present invention adopts a fermentation extraction method to effectively extract walnut peptides from walnut meal, making full use of walnut resources. The walnut peptides provided by the present invention are low in cost and have a certain effect of improving memory. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 Example 1 Walnut peptide gel chromatography molecular weight distribution diagram;
[0024] Figure 2 Example 2 Walnut peptide gel chromatography molecular weight distribution diagram;
[0025] Figure 3 Comparative Example 1: Gel chromatography molecular weight distribution of walnut peptide. DETAILED DESCRIPTION
[0026] Now, various exemplary embodiments of the present invention are described in detail. The methods in the examples are conventional methods unless otherwise specified, and the reagents used are conventional commercially available reagents or reagents prepared by conventional methods unless otherwise specified. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, features and embodiments of the present invention.
[0027] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.
[0028] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.
[0029] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.
[0030] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.
[0031] Walnut meal and walnut protein were purchased from Hebei Lvlei Agriculture and Forestry Technology Co., Ltd., Eurotium cristatum and Aspergillus oryzae were from Beijing Biological Collection Center, alkaline protease and flavor protease were purchased from Nanning Pangbo Bioengineering Co., Ltd., and kiwifruit protease was purchased from Shanghai Guchen Biotechnology Co., Ltd. The protein content was detected according to GB5009.5 National Food Safety Standard Determination of Protein in Food, and the peptide content and molecular weight were detected according to GB / T 22492-2008 Soybean Peptide Powder.
[0032] Example 1
[0033] 1kg of edible walnut meal is evenly sprinkled with water and stirred, the moisture content is controlled to 18.6%, the pile temperature is 45℃, and 0.10~0.12Mpa steam is passed for 5min to soften the raw material. Continue to pass steam at 105℃~125℃ and steam for 30min. Cultivate the Aspergillus oryzae and Aspergillus oryzae in liquid form separately to prepare liquid fermentation agent, with the liquid proportion of Aspergillus oryzae being 5% and the proportion of Aspergillus oryzae being 3%, and spray it evenly on the surface of the sterilized material. Place the inoculated material in a closed, temperature- and humidity-controlled fermentation room for fermentation. The indoor temperature should be maintained at 25℃~35℃; the relative humidity should be maintained at 50%~90%, and ferment for 5 days. Put the fermented material into the enzymolysis tank, add water in a ratio of 1:8, heat to 90℃, and sterilize for 30min; adjust the temperature to 50℃, adjust the pH to 6.5, add 1% cellulose enzyme for 4h; adjust the pH to 7.5, first add 1% alkaline protease for 4h, then adjust the pH to 6.5, add 0.6% flavor protease and 1.5% kiwi protease for 6h, heat to 90℃, and kill the enzyme for 30min. Add 2% bentonite and 4% diatomaceous earth to the enzymolysis solution, decolorize for 60min and filter; the filtrate after decolorization and filtration is filtered with a 7KD ultrafiltration membrane, and then remove inorganic salts and water-soluble free amino acids by nanofiltration, and spray dry to obtain walnut peptide. The protein content of the prepared walnut peptide is 67.3%, the peptide content is 54.1%, and the average molecular weight is 1467.
[0034] Table 1 Example 1 Walnut peptide molecular weight distribution
[0035] Molecular weight range Peak area percentage % >10000 0.8 5000-10000 4 3000-5000 7.68 2000-3000 9.3 1000-2000 22.11 500-1000 24.8 189-500 29.09 <189 2.23
[0036] Example 2
[0037] 1kg of walnut protein is evenly sprinkled with water and stirred, the moisture content is controlled to 20.4%, the pile temperature is 35℃, and 0.10~0.12Mpa steam is passed for 5min to soften the raw material. Continue to pass steam at 105℃~125℃ and steam for 40min. The Aspergillus oryzae and Aspergillus oryzae liquid are cultured separately to prepare liquid fermentation agents, with the Aspergillus oryzae liquid ratio of 4% and Aspergillus oryzae ratio of 4%, and evenly sprayed on the surface of the sterilized material. The inoculated material is placed in a closed, temperature- and humidity-controlled fermentation room for fermentation. The indoor temperature should be maintained at 25℃~35℃; the relative humidity should be maintained at 50%~90%, and fermented for 3 days. Put the fermented material into the enzymolysis tank, add water in a ratio of 1:10, heat to 90℃, and sterilize for 30min; adjust the temperature to 50℃, adjust the pH to 6.5, add 0.5% cellulase for enzymolysis for 3h; adjust the pH to 7.5, first add 1.5% alkaline protease for enzymolysis for 5h, then adjust the pH to 6.5, add 1% flavor protease and 1% kiwi protease for enzymolysis for 5h, heat to 90℃, and kill the enzyme for 30min. Add 2% bentonite and 6% diatomaceous earth to the enzymolysis solution, decolorize for 90min and filter; the filtrate after decolorization and filtration is filtered with a 7KD ultrafiltration membrane, and then remove inorganic salts and water-soluble free amino acids by nanofiltration, and spray dry to obtain walnut peptide. The protein content of the prepared walnut peptide is 82.3%, the peptide content is above 72.6%, and the average molecular weight is 1598Da.
[0038] Table 2 Example 2 Walnut peptide molecular weight distribution
[0039] Molecular weight range Peak area percentage % >10000 4.27 5000-10000 3.17 3000-5000 2.73 2000-3000 2.8 1000-2000 7.45 500-1000 14.96 189-500 63.03 <189 1.58
[0040] Comparative Example 1
[0041] Evenly sprinkle water on 1kg of edible walnut meal and stir it. The moisture content is controlled at 32.5%, the pile temperature is 45℃, and 0.10-0.12Mpa steam is passed for 5 minutes to soften the raw materials. Continue to pass steam at 105℃-125℃ for 30 minutes. Cultivate the Aspergillus niger strain into a liquid fermentation agent with a liquid ratio of 0.5%, and evenly spray it on the surface of the sterilized material. Place the inoculated material in a closed, temperature- and humidity-controlled fermentation room for fermentation. The indoor temperature should be maintained at 25℃-35℃; the relative humidity should be maintained at 50%-90%, and ferment for 5 days. Put the fermented material into the enzymolysis tank, add water in a ratio of 1:8, heat to 90℃, and sterilize for 30min; adjust the temperature to 50℃, adjust the pH to 6.5, add 1% cellulase for 4h; adjust the pH to 7.5, first add 0.2% alkaline protease for 6h, then adjust the pH to 6.5, add 1.5% flavor protease and 0.5% kiwi protease for 6h, heat to 90℃, and kill the enzyme for 30min. Add 2% bentonite and 4% diatomaceous earth to the enzymolysis solution, decolorize for 60min and filter; the filtrate after decolorization and filtration is filtered with a 7KD ultrafiltration membrane, and then remove inorganic salts and water-soluble free amino acids by nanofiltration, and spray dry to obtain walnut peptide. The protein content of the prepared walnut peptide is 51.3%, the peptide content is 42.6%, and the average molecular weight is 3678.
[0042] Table 3 Comparative Example 1 Walnut Peptide Molecular Weight Distribution
[0043] Molecular weight range Peak area percentage % >10000 6.94 5000-10000 9.88 3000-5000 11.41 2000-3000 12.1 1000-2000 21.67 500-1000 21.41 189-500 15.28 <189 1.31
[0044] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.
Claims
1. A method for preparing walnut peptide, characterized in that: The following steps are involved: (1) Stacking: watering the walnut raw materials, stirring and stacking; (2) Fumigation: passing steam to fumigate the raw materials; (3) Inoculation: Prepare a fermentation agent using Eurotium cristatum and / or Aspergillus oryzae and spray it onto the surface of the fumigated raw materials; (4) Fermentation: The inoculated raw materials are placed in an environment with a temperature of 25° C. to 35° C. and a relative humidity of 50% to 90% for fermentation for 2 to 7 days; (5) Enzymatic hydrolysis: add water to the fermented raw materials in a ratio of 1:3-20, heat to 90°C, and heat for 30 minutes; then adjust the temperature to 45-60°C, adjust the pH to 4-7, add 0.1%-3% cellulase for enzymatic hydrolysis for 2-6 hours; adjust the pH to 5-8; add 0.3%-3% alkaline protease for enzymatic hydrolysis for 2-6 hours, then adjust the pH to 5-7, add flavor protease and kiwi protease for enzymatic hydrolysis for 2-6 hours, the addition amount is 0.1%-3%, and the ratio is 1:1-5; heat to 90°C, inactivate the enzyme for 30 minutes to obtain an enzymatic solution; (6) Filtration: Add bentonite and diatomaceous earth to the enzymatic hydrolyzate, decolorize for 20-90 minutes, and filter; the filtrate after decolorization and filtration is filtered using a 7KD ultrafiltration membrane, and then filtered through nanofiltration and spray dried to obtain walnut peptide.
2. The method according to claim 1, characterized in that The walnut raw material in step (1) is walnut meal or walnut protein.
3. The method according to claim 1, characterized in that The walnut raw material in step (1) is walnut meal or walnut protein made from wild walnuts from Changbai Mountain.
4. The method according to claim 1, characterized in that: The moisture content of the walnut raw material in step (1) is 10% to 40%, and the stacking temperature is 10° C. to 60° C.
5. The method according to claim 1, characterized in that The fumigation in step (2) is carried out by introducing 0.10-0.2Mpa steam for 2-10 minutes.
6. The method according to claim 5, characterized in that The fumigation in step (2) is carried out by introducing 0.10-0.12Mpa steam for 3-5 minutes.
7. The method according to claim 1, characterized in that In step (5), the ratio of enzymatic hydrolysis to water is 1:5-10, the pH of cellulase hydrolysis is 5-7, and the enzymatic hydrolysis time is 4-6 hours; the pH of alkaline protease is 6-8, the addition ratio is 0.5%-1.5%, and the enzymatic hydrolysis pH is 6-8; the addition amount of flavor protease and homemade kiwi protease is 0.6%-2%, and the weight ratio is 1:1-3.
8. The method according to claim 1, characterized in that: The added amount of bentonite and diatomite in step (6) is 1%-10% of the total mass, and the mass ratio of bentonite to diatomite is 1:1-6.
9. The method according to claim 8, characterized in that The amount of bentonite and diatomite added in step (6) is 3%-7% of the total mass of the enzymatic hydrolyzate, bentonite and diatomite, and the mass ratio of bentonite to diatomite is 1:2-4.
10. Use of the walnut peptide obtained by the method according to any one of claims 1 to 9 in the preparation of a product for improving memory.