A preparation method of fish-derived collagen peptide

Abstract

The present invention relates to the field of biomaterial technology, and in particular to a method for preparing fish-derived collagen peptides. The preparation method comprises the following steps: adding fish tissue to a first composite solution, extracting collagen at 2 to 15°C, and filtering to obtain a crude collagen extract; wherein the first composite solution comprises a first acid compound, a first alcohol compound, and pepsin; further purifying the obtained crude collagen extract to obtain refined collagen; adding the obtained refined collagen to a second composite solution to react at 2 to 15°C, and performing high-pressure homogenization during the reaction; wherein the second composite solution comprises a second acid compound and a second alcohol compound. The low-temperature acid-alcohol extraction method used in the preparation method of the present invention avoids the problem that the hydrolysis method, the enzyme method, and the alkali method change the structure of collagen, thereby reducing the biological activity, and effectively ensures the protein extraction rate and reduces the microbial content of the product.

Description

Technical Field

[0001] The invention relates to the technical field of biomaterials, and in particular to a method for preparing fish-derived collagen peptides. Background Art

[0002] Collagen is the main component of animal connective tissue. It is a fibrous protein that is widely found in animal skin, cartilage, Achilles tendon and other tissues. Collagen is a triple helix structure composed of three α peptide chains with a molecular weight of about 300kDa. Collagen contains a large number of amino acids, among which hydroxyproline is its characteristic amino acid. There are many types of collagen, and the common types are type I, type II, type III, type V and type XI. Type I collagen is the most abundant and important type of collagen in animals. Fish skin, fish scales, fish bones and other fish tissues also contain rich type I collagen. Extracting collagen from fish scraps realizes the reuse of waste and can reduce environmental pollution. Compared with collagen extracted from mammals, fish-derived collagen reduces the risk of zoonotic diseases, is easier to absorb, and has better biocompatibility, degradability and biological activity.

[0003] Collagen has certain applications in the cosmetics, pharmaceutical and food industries. Collagen stimulates dermal fibroblasts to generate new collagen and tissue, and has a repair and regeneration effect. It can be added to cosmetics as a raw material, or it can be prepared into dressings to promote the repair of skin trauma. Collagen also plays an active role in guiding the regeneration of bone tissue. It can form a biological barrier membrane at the site of bone defects, creating good conditions for the proliferation of regenerated tissue cells. In addition, collagen can also be added to food as a functional substance and nutrient to enhance and maintain good skin elasticity.

[0004] In order to ensure the good efficacy of collagen in cosmetics, it must be made to work in the dermis of the skin. The factors that affect the expression of collagen efficacy are mainly the molecular weight. Large molecular collagen is not easily absorbed by the skin. The methods for reducing the molecular weight of collagen mainly include hydrolysis, acid degradation, alkali degradation and enzyme degradation. The patent with publication number CN104278069A discloses a method for obtaining protein by enzymatic hydrolysis at 37°C. The extraction temperature of this method is relatively high, which can easily reduce the activity of the protein. The patent with publication number CN109480294A discloses a method for obtaining protein by high-temperature hydrolysis. The temperature is 130-135°C, which can easily inactivate the protein. The patent with publication number CN104351849A discloses a method for extracting protein by alkali dissolution, which can easily denature collagen and produce racemization, thereby reducing the activity of the protein. Summary of the invention

[0005] The present invention provides a method for preparing fish-derived collagen peptides. The low-temperature acid-alcohol extraction method used in the preparation method of the present invention avoids the problem that hydrolysis, enzyme and alkali methods change the structure of collagen and thus lead to reduced biological activity, and effectively ensures the protein extraction rate and reduces the microbial content of the product.

[0006] According to a first aspect of the present invention, the present invention provides a method for preparing fish-derived collagen peptides, comprising the following steps:

[0007] Step (1): adding fish tissue to a first composite solution, extracting collagen at 2 to 15° C., and filtering to obtain a crude collagen extract; wherein the first composite solution comprises a first acid compound, a first alcohol compound, and pepsin;

[0008] Step (2): further purifying the crude collagen extract obtained in step (1) to obtain refined collagen;

[0009] Step (3): adding the obtained refined collagen to a second composite solution and reacting at 2-15° C., and performing high-pressure homogenization during the reaction; wherein the second composite solution comprises a second acid compound and a second alcohol compound.

[0010] In the above scheme, a method for preparing fish-derived collagen peptides of the present invention first uses a first composite solution comprising a first acid compound, a first alcohol compound and pepsin to hydrolyze and preliminarily extract collagen from fish tissues. The first acid compound helps dissolve collagen from fish tissues, and pepsin can remove the terminal peptides of collagen, thereby increasing the dissolution rate of collagen. The addition of the first alcohol compound can ensure the biological activity of collagen and effectively reduce the content of microorganisms. The preparation method of the present invention further purifies the crude collagen extract after collagen extraction, thereby increasing the purity of collagen and obtaining purified collagen with high purity. The preparation method of the present invention adds the purified collagen obtained after purification to a second composite solution comprising a second acid compound and a second alcohol compound, and reacts at 2 to 15° C., further effectively extracting collagen peptides from the purified collagen, thereby increasing the extraction efficiency, and simultaneously performing high-pressure homogenization during the reaction of the purified collagen to obtain fish-derived collagen peptides with a stable molecular weight distribution range and concentrated molecular weight. The preparation method of the invention is simple, low in cost, and suitable for wide production and application. The preparation method of the invention can obtain fish-derived collagen peptides with high biological activity, stable molecular weight distribution range, high yield and low cost.

[0011] In order to achieve higher extraction efficiency, further, in step (1), the first acid compound includes one or more of citric acid, acetic acid, hydrochloric acid, carbonic acid, phosphoric acid and chloric acid; and / or, the first alcohol compound includes one or more of pentanediol, butanediol, glycerol and ethylene glycol;

[0012] Preferably, in the first composite solution, the concentration of the first acid compound is 0.1-1.0 mol / L; and / or, in the first composite solution, the mass percentage of the first alcohol compound is 1%-5%; and / or, in the first composite solution, the mass percentage of the pepsin is 0.01%-0.1%. By limiting the concentration of the first acid compound, the mass percentage of the first alcohol compound and the mass percentage of the pepsin to a reasonable range, the acid, alcohol and protease in the first composite solution can achieve a better synergistic effect, and the extraction efficiency can be better improved.

[0013] In order to achieve higher extraction efficiency, further, in step (1), the time for collagen extraction is 12 to 48 hours.

[0014] In order to achieve higher extraction efficiency, further, in step (3), the second acid compound includes one or more of citric acid, acetic acid, hydrochloric acid, carbonic acid, phosphoric acid and chloric acid; preferably, in the second composite solution, the concentration of the second acid compound is 0.001-0.01 mol / L;

[0015] And / or, the second alcohol compound includes one or more of pentanediol, butanediol, propylene glycol and ethylene glycol; preferably, in the second composite solution, the mass percentage of the second alcohol compound is 1% to 5%.

[0016] Furthermore, in step (3), the mass volume ratio of the refined collagen to the second composite solution is 1:100 to 1:500.

[0017] In the above scheme, by limiting the mass volume ratio of the purified collagen to the second composite solution within a reasonable range, the extraction efficiency of collagen can be further improved.

[0018] Furthermore, the reaction time is 24 to 96 hours.

[0019] In the above scheme, by limiting the reaction time within a reasonable range, the purified collagen and the second composite solution can fully react, which can further ensure the activity of the collagen peptide.

[0020] Furthermore, the pressure of the high-pressure homogenization is 5000-15000 psi.

[0021] In the above scheme, by limiting the pressure of high-pressure homogenization within a reasonable range, it is more conducive to obtaining fish-derived collagen peptides with a stable molecular weight distribution range and concentrated molecular weight.

[0022] Furthermore, in step (2), the purification method includes one or more of salting out and re-dissolution, ion chromatography exchange, ultrafiltration, filtration or drying.

[0023] In the above scheme, the purity of fish-derived collagen peptides can be improved by selecting a suitable purification method.

[0024] Furthermore, step (3) further comprises: adjusting the pH value of the solution to 5.5 to 8.5 after the reaction is completed.

[0025] In the above scheme, adjusting the pH value of the solution to a reasonable range after the reaction is completed is beneficial to the subsequent processing and application of fish-derived collagen peptides.

[0026] Furthermore, before adding the fish tissue to the first composite solution, step (1) also includes pre-processing the fish tissue: first, cleaning the excess fish meat, fish fat and impurities visible to the naked eye on the surface of the fish tissue, and then putting the fish tissue into a cleaning solution to clean and remove impurities and remove moisture.

[0027] In the above scheme, before adding the fish tissue to the first composite solution, a pre-treatment step is performed on the fish tissue, which is beneficial to remove impurities in the fish tissue and improve the quality of fish-derived collagen peptides.

[0028] Preferably, the cleaning time is 24 to 96 hours; and / or the weight ratio of the fish tissue to the cleaning solution is 1:30 to 1:100.

[0029] In the above scheme, by limiting the cleaning time and / or the weight ratio of fish tissue to cleaning solution within a reasonable range, the efficiency of removing impurities in fish tissue can be improved, and the quality of fish-derived collagen peptides can be further improved.

[0030] Further, the cleaning solution includes one or more of a saline solution, an alkaline solution or a single purified water;

[0031] Preferably, the salt in the saline solution includes one or more of potassium chloride, sodium chloride, calcium chloride, zinc chloride, ferric chloride, and ammonium chloride; and / or, the alkali in the alkali aqueous solution includes one or more of sodium hydroxide, potassium hydroxide, ammonium hydroxide, barium hydroxide, and calcium hydroxide;

[0032] More preferably, the mass concentration of the salt in the saline solution is 0.5% to 10%; and / or the mass concentration of the alkali in the alkali aqueous solution is 0.1% to 1%.

[0033] In the above scheme, by selecting a cleaning solution of reasonable type and mass concentration, the purpose of more effectively removing impurities in fish tissues can be achieved.

[0034] Furthermore, in step (1), the fish tissue includes fish skin, fish scales or fish bones; the fish in the fish tissue is one of a marine fish and a freshwater fish; preferably, the fish in the fish tissue is selected from one or more of cod, pomfret, sea bass, tilapia, salmon, golden threadfish, crucian carp, grass carp, catfish, silver carp, bighead carp or hairtail.

[0035] The raw materials adopted in the preparation method of the present invention are fish tissues such as fish skin, fish scales, fish bones, etc., which solves the treatment of fish waste, realizes the recycling of waste, and reduces environmental pollution.

[0036] Beneficial effects of the present invention:

[0037] The method for preparing a fish-derived collagen peptide of the present invention adopts a low-temperature acid-alcohol extraction method to prepare a high-purity fish-derived collagen peptide with high biological activity and a stable molecular weight distribution range. This method can avoid the problem of hydrolysis, enzyme method or alkali method changing the collagen structure and thus causing reduced biological activity, and can effectively ensure the protein extraction rate and reduce the microbial content of the product.

[0038] The raw materials adopted in the preparation method of fish-derived collagen peptides are fish skin, fish scales, fish bones and other fish tissues, which solves the treatment of fish waste, realizes the recycling of waste and reduces environmental pollution.

[0039] Compared with collagen peptides extracted from mammals, the fish-derived collagen peptides prepared by the preparation method of the present invention reduce the risk of zoonotic diseases, are easier to absorb, and have very good biocompatibility and degradability. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Example 1

[0042] This embodiment provides a method for preparing fish-derived collagen peptides, comprising the following steps:

[0043] Step (1): Use a scraper to clean the fish meat, fish fat and impurities visible to the naked eye on the surface of the fish tissue. Use a slicer to break the fish tissue into small pieces, put it into a 10% potassium chloride salt solution for cleaning, the ratio of fish tissue to cleaning solution is 1:100, the cleaning time is 24 hours, and then use a centrifuge to remove moisture.

[0044] The cleaned fish tissue was put into a composite solution containing 0.1% pepsin, 1.0 mol / L acetic acid and 1% pentanediol, and reacted at 2-15° C. for 36 hours, and the crude collagen extract was filtered.

[0045] Step (2): The crude collagen extract is further purified by an ultrafiltration system and a drying system in sequence to obtain refined collagen.

[0046] Step (3): The purified collagen was mixed with a composite solution of 0.01 mol / L acetic acid and 1% pentanediol at a ratio of 1:100, and reacted at 2-15°C for 48 hours. During the reaction, a high-pressure homogenizer was used to act on the collagen solution at a pressure of 15,000 psi. After the reaction, the pH of the collagen solution was adjusted to 5.5-8.5.

[0047] Example 2

[0048] This embodiment provides a method for preparing fish-derived collagen peptides, comprising the following steps:

[0049] Step (1): Use a scraper to clean the fish meat, fish fat and impurities visible to the naked eye on the surface of the fish tissue. Use a slicer to break the fish tissue into small pieces, and then wash them in 0.5% sodium chloride salt solution and 0.1% sodium hydroxide alkaline solution in turn. The ratio of fish tissue to washing solution is 1:30, and the washing time is 96 hours respectively. Use a centrifuge to remove moisture.

[0050] The cleaned fish tissue was put into a 0.5 mol / L acetic acid solution containing 0.03% pepsin and a 5% pentanediol composite solution for reaction at 2-15° C. for 48 hours, and the crude collagen extract was obtained by filtering.

[0051] Step (2): The crude collagen extract is further purified by salting out, redissolving and drying to obtain refined collagen.

[0052] Step (3): The purified collagen was mixed with a composite solution of 0.001 mol / L hydrochloric acid and 1% pentanediol at a ratio of 1:500, and reacted at 2-15°C for 96 hours. During the reaction, a high-pressure homogenizer was used to act on the collagen solution at a pressure of 5000 psi. After the shearing was completed, the pH of the collagen solution was adjusted to 5.5-8.5 with an acetic acid solution.

[0053] Example 3

[0054] This embodiment provides a method for preparing fish-derived collagen peptides, comprising the following steps:

[0055] Step (1): Use a scraper to clean the fish meat, fish fat and impurities visible to the naked eye on the surface of the fish tissue. Use a slicer to break the fish tissue into small pieces, wash it with 1% potassium hydroxide alkaline solution, the ratio of fish tissue to washing solution is 1:30, the washing time is 24 hours, and then use a centrifuge to remove moisture.

[0056] The cleaned fish tissue was placed in a composite solution of 0.1 mol / L citric acid and 5% butanediol containing 0.01% pepsin at 2-15° C. for 12 hours, and the crude collagen extract was obtained by filtering.

[0057] Step (2): The crude collagen extract is further purified by salting out, redissolving and drying to obtain refined collagen.

[0058] Step (3): The purified collagen solution is mixed with a 0.005 mol / L citric acid solution and a 5% butanediol composite solution at a ratio of 1:300, and reacted at 2-15°C for 24 hours. During the reaction, a high-pressure homogenizer is used to act on the collagen solution at a pressure of 10,000 psi. After the reaction, the pH of the collagen solution is adjusted to 6.5-8.5.

[0059] Example 4

[0060] This embodiment provides a method for preparing fish-derived collagen peptides, which is different from that of Embodiment 1 in that an equal amount of propylene glycol is used in the composite solution in step (1) and the composite solution in step (3) instead of pentanediol.

[0061] Example 5

[0062] This embodiment provides a method for preparing fish-derived collagen peptides, which is different from that of Embodiment 1 in that an equal amount of butanediol is used in place of pentanediol in the composite solution in step (1) and the composite solution in step (3).

[0063] Example 6

[0064] This embodiment provides a method for preparing fish-derived collagen peptides, which is different from that of Embodiment 3 in that filtration is used instead of salting out and redissolution in step (2), and the remaining steps are the same as those of Embodiment 3.

[0065] Example 7

[0066] This embodiment provides a method for preparing fish-derived collagen peptides, which is different from that of Embodiment 3 in that in step (2), molecular sieve chromatography and ion exchange column separation are used instead of salting out and redissolution, and the remaining steps are the same as those of Embodiment 3.

[0067] The fish-derived collagen peptides obtained in Examples 1-7 were subjected to the following performance tests:

[0068] Protein molecular weight distribution test: determined by the general chapter 0541 electrophoresis method and MALDI-TOF-MS method of the Pharmacopoeia of the People's Republic of China (2020 edition).

[0069] Test on the extraction rate of fish-derived collagen peptides: The protein content determination method of General Chapter 0731 of the Pharmacopoeia of the People's Republic of China (2020 edition) was used for determination.

[0070] Purity test of fish-derived collagen peptides: The purity of collagen was determined using the YY / T1453-2016 Type I collagen characterization method for tissue engineering medical device products.

[0071] The biological activity of fish collagen peptides and the microbial status of the product are tested: keratinocytes and fibroblasts are used as the test system to detect cell migration rate, relative inhibition rate of active oxygen, and changes in elastin content in fibroblasts to evaluate the biological activity of the product. The microbial status of the product is evaluated according to the microbial testing method in Chapter 5 of the Cosmetic Safety Technical Specifications (2015 Edition).

[0072] The test results are shown in Table 1 below.

[0073] Table 1

[0074]

[0075] It can be seen from the results in Table 1 that the preparation method of the present invention can obtain fish-derived collagen peptides with a molecular weight distribution of 0.5-10 kDa, an extraction rate of more than 8%, a purity of up to 99% and significant biological activity, and can effectively reduce the number of colony growth of fish-derived collagen peptides.

[0076] Comparative Example 1

[0077] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 1 in that a high-pressure homogenizer is not used to act on the collagen liquid in step (3), and the remaining steps are the same as those in Example 1.

[0078] Comparative Example 2

[0079] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 1 in that 0.01 mol / L acetic acid is not added during the reaction in step (3), and the remaining steps are the same as Example 1.

[0080] The fish-derived collagen peptides obtained in Comparative Examples 1 and 2 were tested for the distribution of protein molecular weight. The test results are shown in Table 2 below.

[0081] Table 2

[0082] project Molecular weight distribution Example 1 The molecular weight of the protein is concentrated in the range of 0.5 to 2 kDa Comparative Example 1 The molecular weight of the protein is concentrated in the range of 75-100 kDa Comparative Example 2 The molecular weight of the protein is concentrated in the range of 100 to 240 kDa

[0083] It can be seen from the results in Table 2 that the addition of acid solution and the use of a high-pressure homogenization step in the further reaction process of the refined collagen in step (3) of the preparation method of a fish-derived collagen peptide of the present invention have a great influence on the molecular weight distribution of the final fish-derived collagen peptide. The addition of acid solution combined with the high-pressure homogenization step is conducive to obtaining a stable fish-derived collagen peptide with a molecular weight concentrated in the range of 0.5 to 2 kDa.

[0084] Comparative Example 3

[0085] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 2 in that the composite solution in step (1) does not contain acetic acid solution, and the remaining steps are the same as Example 2.

[0086] Comparative Example 4

[0087] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 2 in that the composite solution in step (1) does not contain pepsin, and the remaining steps are the same as those in Example 2.

[0088] The fish-derived collagen peptides obtained in Comparative Examples 3 and 4 were tested for extraction rate, and the results are shown in Table 3 below.

[0089] Table 3

[0090] project Collagen extraction rate (%) Example 2 10.2 Comparative Example 3 3.3 Comparative Example 4 5.6

[0091] It can be seen from the results in Table 3 that the addition of acid compounds and pepsin in the step (1) of the preparation process of the crude collagen extract of the fish-derived collagen peptide of the present invention will affect the final extraction rate of the fish-derived collagen peptide. The present invention can obtain fish-derived collagen peptides with a high extraction rate under an environment of 2 to 15°C by the mutual coordination of acid compounds, alcohol compounds and pepsin.

[0092] Comparative Example 5

[0093] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 1 in that the reaction temperatures in step (1) and step (3) are both 37°C.

[0094] Comparative Example 6

[0095] This comparative example provides a method for preparing fish-derived collagen peptides, which is different from Example 1 in that the composite solution in step (1) and the composite solution in step (3) do not contain pentanediol.

[0096] The biological activity of the fish-derived collagen peptides of Comparative Example 5 and Comparative Example 6 and the microbial status of the products were tested, and the test results are shown in Table 4 below.

[0097] Table 4

[0098]

[0099]

[0100] It can be seen from the results in Table 4 that the fish-derived collagen peptide prepared by the preparation method of Example 1 exhibits significant biological activity advantages over Comparative Examples 5 and 6, and effectively reduces the number of colony growth.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing fish-derived collagen peptide, characterized in that: The steps include: Step (1): adding fish tissue to a first composite solution, extracting collagen at 2-15° C., and filtering to obtain a crude collagen extract; wherein the first composite solution is composed of a first acid compound, a first alcohol compound, and pepsin; and the fish tissue includes fish skin, fish scales, or fish bones; Step (2): further purifying the crude collagen extract obtained in step (1) to obtain refined collagen; Step (3): adding the obtained refined collagen to a second composite solution and reacting at 2 to 15° C., and performing high pressure homogenization during the reaction; wherein the second composite solution is composed of a second acid compound and a second alcohol compound; and the reaction time is 24 to 96 hours; In step (1), the first acid compound is selected from one or more of citric acid, acetic acid, and hydrochloric acid; the first alcohol compound is selected from one of pentanediol, butanediol, and glycerol; In the first composite solution, the concentration of the first acid compound is 0.1-1.0 mol / L; in the first composite solution, the mass percentage of the first alcohol compound is 1%-5%; in the first composite solution, the mass percentage of the pepsin is 0.01%-0.1%; In step (1), the collagen extraction time is 12 to 48 hours; In step (3), the second acid compound is selected from one or more of citric acid, acetic acid, and hydrochloric acid; in the second composite solution, the concentration of the second acid compound is 0.001 to 0.01 mol / L; The second alcohol compound is selected from one of pentanediol, butanediol and propylene glycol; in the second composite solution, the mass percentage of the second alcohol compound is 1% to 5%; The purification method comprises one or more of salting out and re-dissolving, ion chromatography exchange, ultrafiltration, filtration or drying.

2. The preparation method according to claim 1, characterized in that: In step (3), the mass volume ratio of the refined collagen to the second composite solution is 1:100 to 1:

500.

3. The preparation method according to claim 1, characterized in that: In step (3), the pressure of the high-pressure homogenization is 5000 to 15000 psi.

4. The preparation method according to claim 1, characterized in that: In step (2), the purification method includes salting out, re-dissolving and drying.

5. The preparation method according to claim 1, characterized in that: Step (3) also includes: adjusting the pH value of the solution to 5.5-8.5 after the reaction is completed.

6. The preparation method according to claim 1, characterized in that: Before adding the fish tissue to the first composite solution, step (1) further includes pre-treating the fish tissue: first, cleaning the excess fish meat, fish fat and impurities visible to the naked eye on the surface of the fish tissue, and then putting the fish tissue into a cleaning solution to clean and remove impurities and remove moisture.

7. The preparation method according to claim 6, characterized in that: The cleaning time is 24 to 96 hours.

8. The preparation method according to claim 6, characterized in that: The weight ratio of the fish body tissue to the cleaning solution is 1:30 to 1:

100.

9. The preparation method according to any one of claims 6 to 8, characterized in that: The cleaning solution includes one or more of a saline solution, an alkaline solution or pure water.

10. The preparation method according to claim 9, characterized in that: The salt in the brine solution includes one or more of potassium chloride, sodium chloride, calcium chloride, zinc chloride, ferric chloride and ammonium chloride.

11. The preparation method according to claim 9, characterized in that: The alkali in the alkaline aqueous solution includes one or more of sodium hydroxide, potassium hydroxide, ammonium hydroxide, barium hydroxide and calcium hydroxide.

12. The preparation method according to claim 9, characterized in that: The mass concentration of salt in the saline solution is 0.5% to 10%.

13. The preparation method according to claim 9, characterized in that: The mass concentration of the alkali in the alkali aqueous solution is 0.1% to 1%.

14. The preparation method according to claim 1, characterized in that: In step (1), the fish body tissue includes fish skin, fish scales or fish bones; the fish in the fish body tissue is a kind of marine fish or freshwater fish.

15. The preparation method according to claim 14, characterized in that: The fish in the fish body tissue is selected from one or more of cod, pomfret, sea bass, tilapia, salmon, golden threadfish, crucian carp, grass carp, catfish, silver carp, bighead carp or hairtail.

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