Efficient amino acid peptide prepared from hydrolyzed fish protein and preparation method of efficient amino acid peptide

Abstract

The invention provides efficient amino acid peptide prepared by hydrolyzing fish protein and a preparation method of the efficient amino acid peptide, and belongs to the technical field of food protein and food protein processing. Through the synergistic effect of the amine-captured nano ligand microspheres, the tannic acid-chitosan compound and the sodium alginate / chitosan oligosaccharide composite powder, the problems of fishy smell, color and peptide aggregation are solved from the molecular level; the amine capture nano ligand microspheres form a porous structure through crosslinking of chitosan and sodium tripolyphosphate, the stability and the selective adsorption capacity are enhanced through genipin, and fishy smell molecules such as trimethylamine oxide are efficiently removed; the tannic acid-chitosan compound selectively removes heme and oxidized pigment molecules through coordination complexation and electrostatic interaction, and the color and luster of hydrolysate are remarkably improved; the sodium alginate and chitosan oligosaccharide composite system inhibits peptide aggregation and improves transparency through electrostatic repulsion, hydrogen bonds and a supramolecular network, and a fishy-smell-free, colorless, transparent and stable efficient amino acid peptide product is prepared.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of food protein and food protein processing technology, and relates to a high-efficiency amino acid peptide prepared from hydrolyzed fish protein and a preparation method thereof. BACKGROUND

[0002] In today's food industry, fish protein hydrolysate is widely used in transparent beverages and special medical foods as an important functional ingredient. However, it still faces many challenges to prepare fish protein hydrolysate with no obvious fishy smell, light and transparent color, and good stability.

[0003] Firstly, trimethylamine oxide and other nitrogen-containing compounds naturally existing in fish tissues will decompose into volatile amine substances with fishy smell during hydrolysis and storage, which not only affects the taste of the product, but also limits its application in beverages. Traditional deodorization methods such as heating or activated carbon adsorption often cannot completely remove the fishy smell, and may also lose a large amount of nutritional ingredients.

[0004] Secondly, hematin and other pigment products in fish muscle will cause the product color to become darker during hydrolysis or storage, resulting in a dark or yellowish-brown color that is not suitable for transparent beverages. This reduces the market acceptance of fish protein hydrolysate, and although common decolorizing agents can remove these pigments, they often cause oxidative damage or loss of peptides.

[0005] Finally, fish proteins or small peptides are prone to aggregation and precipitation during hydrolysis or storage, resulting in turbidity or flocculation, which not only affects the appearance and stability of the product, but also may reduce its functionality. Therefore, how to effectively inhibit the aggregation of proteins / peptides is another big difficulty in preparing high-quality fish protein hydrolysate. SUMMARY

[0006] To solve the above problems, the present application provides a high-efficiency amino acid peptide prepared from hydrolyzed fish protein and a preparation method thereof. The present application solves the problems of fishy smell, color and peptide aggregation at the molecular level through the synergistic effect of amine-capturing nano-ligand microspheres, tannic acid-chitosan complexes and sodium alginate / chitooligosaccharide composite powder. The amine-capturing nano-ligand microspheres utilize the crosslinking of chitosan and sodium tripolyphosphate to form a porous structure, and through the use of genipin to enhance the stability and selective adsorption capacity, the amine-capturing nano-ligand microspheres can efficiently remove odor molecules such as trimethylamine oxide; the tannic acid-chitosan complex selectively removes hematin and oxidized pigment molecules through coordination complexation and electrostatic interaction, significantly improving the color of the hydrolysate; the sodium alginate and chitooligosaccharide composite system inhibits peptide aggregation and improves transparency through electrostatic repulsion, hydrogen bonding and supramolecular network. Finally, a high-efficiency amino acid peptide product with no fishy smell, no color, transparency and stability is successfully prepared.

[0007] To achieve this purpose, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a method for preparing high-efficiency amino acid peptides from hydrolyzed fish proteins, which comprises:

[0009] The headless and boneless fish meat is mixed with deionized water to obtain fish meat slurry; the fish meat slurry is heated and the pH is adjusted to obtain a pretreated enzymatic hydrolysate, neutral protease is added to obtain reaction liquid A, the reaction is stirred and amine capture nanoligand microspheres are added at the same time to obtain reaction liquid B; then the temperature is raised and kept constant, and then cooled to obtain reaction liquid C, tannic acid-chitosan complex is added and stirring is continued, centrifugation is performed to obtain reaction liquid D, sodium alginate / chitooligosaccharide composite powder is added and uniformly dispersed to obtain reaction liquid E, and centrifugation, vacuum concentration and freeze-drying are performed to obtain high-efficiency amino acid peptides prepared from hydrolyzed fish proteins.

[0010] As a preferred technical solution of the present application, the mass ratio of the fish meat to deionized water is 1:(3-5), for example, it can be 1:3, 1:3.2, 1:3.4, 1:3.6, 1:3.8, 1:4, 1:4.2, 1:4.4, 1:4.6, 1:4.8 or 1:5, but is not limited to the listed values, and other values not listed in this range are also applicable.

[0011] In some optional embodiments, the fish meat slurry is heated to 45-50℃, for example, it can be 45℃, 45.5℃, 46℃, 46.5℃, 47℃, 47.5℃, 48℃, 48.5℃, 49℃, 49.5℃ or 50℃, but is not limited to the listed values, and other values not listed in this range are also applicable.

[0012] In some optional embodiments, the pH of the fish meat slurry after heating is adjusted to 6.5-7.5, for example, it can be 6.5, 6.6, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4 or 7.5, but is not limited to the listed values, and other values not listed in this range are also applicable.

[0013] In some optional embodiments, the amount of neutral protease added is 1%-2% of the mass of the pretreated enzymatic hydrolysate, for example, it can be 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9% or 2%, but is not limited to the listed values, and other values not listed in this range are also applicable.

[0014] In some alternative embodiments, the stirring speed of the reaction liquid A is 100-150 rpm, for example, it can be 100 rpm, 105 rpm, 110 rpm, 115 rpm, 120 rpm, 125 rpm, 130 rpm, 135 rpm, 140 rpm, 145 rpm or 150 rpm, but not limited to the listed values, and other values not listed in the range are also applicable.

[0015] In some alternative embodiments, the stirring time of the reaction liquid A is 1-2 h, for example, it can be 1 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, 1.6 h, 1.7 h, 1.8 h, 1.9 h or 2 h, but not limited to the listed values, and other values not listed in the range are also applicable.

[0016] In some alternative embodiments, the amount of amine-captured nanoligand microspheres is 0.5%-1.0% of the pretreated enzymatic hydrolysate, for example, it can be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95% or 1.0%, but not limited to the listed values, and other values not listed in the range are also applicable.

[0017] In some alternative embodiments, the amine-captured nanoligand microspheres are added within 10-20 min after the start of the stirring reaction of the reaction liquid A, for example, it can be 10 min, 11 min, 12 min, 13 min, 14 min, 15 min, 16 min, 17 min, 18 min, 19 min or 20 min, but not limited to the listed values, and other values not listed in the range are also applicable.

[0018] In some alternative embodiments, the reaction liquid B is heated to 80-90°C, for example, it can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, but not limited to the listed values, and other values not listed in the range are also applicable.

[0019] In some alternative embodiments, the reaction liquid B is heated for 10-15 min, for example, it can be 10 min, 10.5 min, 11 min, 11.5 min, 12 min, 12.5 min, 13 min, 13.5 min, 14 min, 14.5 min or 15 min, but not limited to the listed values, and other values not listed in the range are also applicable.

[0020] In some optional embodiments, the reaction liquid B is cooled to 40-50℃ after constant temperature keeping to obtain reaction liquid C, for example, it can be 40℃, 41℃, 42℃, 43℃, 44℃, 45℃, 46℃, 47℃, 48℃, 49℃ or 50℃, but not only limited to the listed values, other values not listed in the range are also applicable.

[0021] In some optional embodiments, the feeding amount of the tannic acid-chitosan complex is 0.4%-0.6% of the mass of the pretreated enzymatic hydrolysate, for example, it can be 0.4%, 0.42%, 0.44%, 0.46%, 0.48%, 0.50%, 0.52%, 0.54%, 0.56%, 0.58% or 0.6%, but not only limited to the listed values, other values not listed in the range are also applicable.

[0022] In some optional embodiments, the reaction liquid C continues to be stirred for 40-60min after adding the tannic acid-chitosan complex, for example, it can be 40min, 42min, 44min, 46min, 48min, 50min, 52min, 54min, 56min, 58min or 60min, but not only limited to the listed values, other values not listed in the range are also applicable.

[0023] In some optional embodiments, the feeding amount of the sodium alginate / chitooligosaccharide complex powder is 0.3%-0.5% of the mass of the pretreated enzymatic hydrolysate, for example, it can be 0.3%, 0.32%, 0.34%, 0.36%, 0.38%, 0.40%, 0.42%, 0.44%, 0.46%, 0.48% or 0.5%, but not only limited to the listed values, other values not listed in the range are also applicable.

[0024] The preparation method of the amine capture nano-ligand microspheres is as follows:

[0025] Chitosan is added into the glacial acetic acid solution to obtain a chitosan dispersion liquid; a sodium tripolyphosphate solution and a genipin dispersion liquid are respectively prepared, the chitosan dispersion liquid is dropped into the sodium tripolyphosphate solution and continuously stirred to obtain a first mixed liquid, the genipin dispersion liquid is dropped into the first mixed liquid and continuously stirred to obtain a second mixed liquid, and the amine capture nano-ligand microspheres are obtained by centrifugation, washing and drying.

[0026] As a preferred technical solution of the present application, the concentration of the glacial acetic acid solution is 0.5%-1%, for example, it can be 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95% or 1%, but not only limited to the listed values, other values not listed in the range are also applicable.

[0027] In some alternative embodiments, the mass fraction of the chitosan dispersion solution is 1 wt.% - 2 wt.%, for example, it can be 1 wt.%, 1.1 wt.%, 1.2 wt.%, 1.3 wt.%, 1.4 wt.%, 1.5 wt.%, 1.6 wt.%, 1.7 wt.%, 1.8 wt.%, 1.9 wt.%, or 2 wt.%, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0028] In some alternative embodiments, the mass fraction of the sodium tripolyphosphate solution is 1 wt.% - 2 wt.%, for example, it can be 1 wt.%, 1.1 wt.%, 1.2 wt.%, 1.3 wt.%, 1.4 wt.%, 1.5 wt.%, 1.6 wt.%, 1.7 wt.%, 1.8 wt.%, 1.9 wt.%, or 2 wt.%, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0029] In some alternative embodiments, the mass fraction of the genipin dispersion solution is 0.1 wt.% - 0.2 wt.%, for example, it can be 0.1 wt.%, 0.11 wt.%, 0.12 wt.%, 0.13 wt.%, 0.14 wt.%, 0.15 wt.%, 0.16 wt.%, 0.17 wt.%, 0.18 wt.%, 0.19 wt.%, or 0.2 wt.%, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0030] In some alternative embodiments, the temperature of the chitosan dispersion solution dropping into the sodium tripolyphosphate solution is 25 - 35 °C, for example, it can be 25 °C, 26 °C, 27 °C, 28 °C, 29 °C, 30 °C, 31 °C, 32 °C, 33 °C, 34 °C, or 35 °C, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0031] In some alternative embodiments, the mass ratio of chitosan to sodium tripolyphosphate in the first mixed solution is (5 - 8) : 1, for example, it can be 5:1, 5.3:1, 5.6:1, 5.9:1, 6.2:1, 6.5:1, 6.8:1, 7.1:1, 7.4:1, 7.7:1, or 8:1, but not limited to the listed values, other values not listed in the range of values are also applicable.

[0032] In some optional embodiments, the rotation speed of the chitosan dispersion solution when stirred after being dropped into the sodium tripolyphosphate solution is 200-400 rpm, for example, it can be 200 rpm, 220 rpm, 240 rpm, 260 rpm, 280 rpm, 300 rpm, 320 rpm, 340 rpm, 360 rpm, 380 rpm or 400 rpm, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0033] In some optional embodiments, the mass ratio of genipin to sodium tripolyphosphate in the second mixed solution is 1:(2-4), for example, it can be 1:2, 1:2.2, 1:2.4, 1:2.6, 1:2.8, 1:3, 1:3.2, 1:3.4, 1:3.6, 1:3.8 or 1:4, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0034] In some optional embodiments, the genipin dispersion solution is dropped into the first mixed solution and continues to be stirred for 2-3 h, for example, it can be 2 h, 2.1 h, 2.2 h, 2.3 h, 2.4 h, 2.5 h, 2.6 h, 2.7 h, 2.8 h, 2.9 h, 3 h, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0035] The preparation method of the tannic acid-chitosan complex is as follows:

[0036] A tannic acid dispersion solution is prepared, and the pH is adjusted to obtain a tannic acid solution; a chitosan dispersion solution is prepared; the tannic acid solution is dropped into the chitosan dispersion solution, and stirring reaction is performed to obtain a complexation reaction solution; centrifugation, washing and drying are performed to obtain the tannic acid-chitosan complex.

[0037] As a preferred technical solution of the present application, the mass fraction of the tannic acid dispersion solution is 1wt.%-3wt.%, for example, it can be 1wt.%, 1.2wt.%, 1.4wt.%, 1.6wt.%, 1.8wt.%, 2wt.%, 2.2wt.%, 2.4wt.%, 2.6wt.%, 2.8wt.% or 3wt.%, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0038] In some optional embodiments, the pH of the tannic acid dispersion solution is adjusted to 5-6, for example, it can be 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9 or 6, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0039] In some alternative embodiments, the mass fraction of the chitosan dispersion solution is 1wt.%-2wt.%, for example, it can be 1wt.%, 1.1wt.%, 1.2wt.%, 1.3wt.%, 1.4wt.%, 1.5wt.%, 1.6wt.%, 1.7wt.%, 1.8wt.%, 1.9wt.% or 2wt.%, but not limited to the listed values, other values not listed in the range are also applicable.

[0040] In some alternative embodiments, the mass ratio of the tannic acid to chitosan is (0.8-1.2):1, for example, it can be 0.8:1, 0.84:1, 0.88:1, 0.92:1, 0.96:1, 1.0:1, 1.04:1, 1.08:1, 1.12:1, 1.16:1 or 1.2:1, but not limited to the listed values, other values not listed in the range are also applicable.

[0041] In some alternative embodiments, the tannic acid solution is added dropwise to the chitosan dispersion solution and stirred for 50-60min, for example, it can be 50min, 51min, 52min, 53min, 54min, 55min, 56min, 57min, 58min, 59min or 60min, but not limited to the listed values, other values not listed in the range are also applicable.

[0042] The preparation method of the sodium alginate / chitooligosaccharide composite powder is as follows:

[0043] A pre-sodium alginate solution is prepared, and the pH is adjusted to obtain a sodium alginate solution; a chitooligosaccharide solution is prepared; the sodium alginate solution and the chitooligosaccharide solution are mixed to obtain a mixed reaction solution, which is stirred and reacted, calcium chloride solution is added and uniformly stirred to obtain a pretreated reaction solution, which is freeze-dried to obtain a sodium alginate / chitooligosaccharide composite powder.

[0044] As a preferred technical solution of the present application, the mass fraction of the pre-sodium alginate solution is 2wt.%-3wt.%, for example, it can be 2wt.%, 2.1wt.%, 2.2wt.%, 2.3wt.%, 2.4wt.%, 2.5wt.%, 2.6wt.%, 2.7wt.%, 2.8wt.%, 2.9wt.% or 3wt.%, but not limited to the listed values, other values not listed in the range are also applicable.

[0045] In some optional embodiments, the pH of the pre-sodium alginate solution is adjusted to 6.5-7, for example, it can be 6.5, 6.55, 6.6, 6.65, 6.7, 6.75, 6.8, 6.85, 6.9, 6.95 or 7, but not only limited to the listed values, other values not listed in the range are also applicable.

[0046] In some optional embodiments, the mass fraction of the chitosan oligosaccharide solution is 3wt.%-5wt.%, for example, it can be 3wt.%, 3.2wt.%, 3.4wt.%, 3.6wt.%, 3.8wt.%, 4wt.%, 4.2wt.%, 4.4wt.%, 4.6wt.%, 4.8wt.% or 5wt.%, but not only limited to the listed values, other values not listed in the range are also applicable.

[0047] In some optional embodiments, the volume ratio of the sodium alginate solution mixed with the chitosan oligosaccharide solution is 6:4-8:2, for example, it can be 6:4, 6.2:3.8, 6.4:3.6, 6.6:3.4, 6.8:3.2, 7:3, 7.2:2.8, 7.4:2.6, 7.6:2.4, 7.8:2.2 or 8:2, but not only limited to the listed values, other values not listed in the range are also applicable.

[0048] In some optional embodiments, the stirring speed of the mixed reaction solution is 50-100rpm, for example, it can be 50rpm, 55rpm, 60rpm, 65rpm, 70rpm, 75rpm, 80rpm, 85rpm, 90rpm, 95rpm or 100rpm, but not only limited to the listed values, other values not listed in the range are also applicable.

[0049] In some optional embodiments, the stirring time of the mixed reaction solution is 60-80min, for example, it can be 60min, 62min, 64min, 66min, 68min, 70min, 72min, 74min, 76min, 78min or 80min, but not only limited to the listed values, other values not listed in the range are also applicable.

[0050] In some alternative embodiments, the mass fraction of calcium chloride is 0.01wt.%-0.05wt.%, for example, it can be 0.01wt.%, 0.014wt.%, 0.018wt.%, 0.022wt.%, 0.026wt.%, 0.03wt.%, 0.034wt.%, 0.038wt.%, 0.042wt.%, 0.046wt.% or 0.05wt.%, but not limited to the listed values, other unlisted values within the range are also applicable.

[0051] In some alternative embodiments, the mass ratio of calcium chloride to sodium alginate is (0.1-0.2):1, for example, it can be 0.1:1, 0.11:1, 0.12:1, 0.13:1, 0.14:1, 0.15:1, 0.16:1, 0.17:1, 0.18:1, 0.19:1 or 0.2:1, but not limited to the listed values, other unlisted values within the range are also applicable.

[0052] In a second aspect, the present application provides a high-efficiency amino acid peptide prepared by hydrolyzing fish protein.

[0053] The application of fish protein products in functional drinks or transparent food ingredients is limited by incomplete removal of fishy smell, poor color, and protein / peptide aggregation leading to turbidity. Among them, the main sources of fishy smell are oxidized trimethylamine, trimethylamine, ammonia and other amine small molecules. These substances are extremely volatile, giving the product an unpleasant odor and seriously affecting the taste. To solve this problem, amine-capturing nanoligand microspheres were introduced in this experiment. Chitosan, as a natural polysaccharide, has a molecular structure rich in amino and hydroxyl groups, which can form a stable chitosan microsphere structure through ionic cross-linking with sodium tripolyphosphate. The specific surface area of cross-linked chitosan microspheres increases significantly, providing abundant sites for the adsorption of amine small molecules. In addition, genipin, as a natural cross-linking agent, forms covalent bonds with the amino groups of chitosan through its ester groups, not only further stabilizing the microsphere structure, but also forming a porous network on the microsphere surface through its unique molecular properties, providing hydrophobic and hydrophilic regions, and enhancing the selective adsorption capacity of the microspheres for amine small molecules. In this system, the amino groups in the chitosan microspheres can capture positively charged amine molecules such as trimethylamine through hydrogen bonding and electrostatic adsorption, while the porous structure of the microspheres further increases the physical adsorption sites for amine molecules, achieving efficient deodorization through the dual mechanism of "physical adsorption + chemical complexation".

[0054] The color of fish protein hydrolysate can be darkened by the presence of heme, iron porphyrin, polyphenol oxidation products and other pigment molecules, which can affect the transparency and appearance of the product. To solve this problem, tannic acid-chitosan complex was introduced in this experiment to selectively remove pigment molecules through coordination complexation, electrostatic interaction and hydrogen bonding. The amino groups in chitosan have a certain coordination ability to the metal ions in the center of heme, which can bind through weak coordination bonds to reduce the solubility of heme, making it more easily settled. At the same time, tannic acid, as a natural polyphenol, can form a stable complex with iron ions in heme through coordination with its phenolic hydroxyl groups. In addition, tannic acid molecules can also form π-π stacking with oxidation polyphenol browning products, combine with other pigment molecules and precipitate together. Through the hydrogen bonding between tannic acid and chitosan, the two form a complex and provide more functional groups in the system. The electrostatic interaction between the cationic properties of chitosan and the anionic properties of tannic acid further enhances the capture ability of pigment molecules. Finally, the complex formed has excellent settling performance, making it easier for the combined pigment molecules to be removed by centrifugation, thereby improving the color of the hydrolysate.

[0055] Even if the fish protein is hydrolyzed, part of the high molecular weight peptide segments may still aggregate due to hydrophobic interaction, electrostatic interaction or pH change, resulting in turbidity or flocculation, affecting the transparency and stability of the product. Therefore, in this experiment, the complex system formed by sodium alginate and chitooligosaccharide was used to regulate the surrounding microenvironment of the peptide molecules, effectively inhibit the aggregation, and disperse the peptide molecules by forming a stable supramolecular structure. Sodium alginate is an anionic polysaccharide, and its carboxyl groups ionize under neutral conditions, providing electrostatic repulsion for peptide molecules to prevent mutual attraction between peptide molecules. The hydrophilicity of the carboxyl group further helps to form a hydration shell in the aqueous solution, increasing the solubility of the peptide molecules and thus reducing the risk of aggregation. Chitooligosaccharide forms reversible hydrogen bonds with peptide molecules through its amino groups, while providing certain hydrophobic interactions to regulate the conformation of peptide molecules. The low molecular weight of chitooligosaccharide allows it to be uniformly distributed in the solution, significantly slowing down the aggregation trend of the peptide segments. The complex of sodium alginate and chitooligosaccharide further forms a supramolecular network through electrostatic interaction, hydrogen bonding and hydrophobic interaction. This network can wrap the peptide molecules, reduce their free diffusion in the solution, and form a physical barrier on the surface of the peptide molecules to prevent the aggregation of hydrophobic peptide segments. In addition, the introduction of calcium chloride enhances the gelation properties of sodium alginate, making the complex powder more stable. Through the above synergistic effect, the turbidity problem of fish protein hydrolysate is finally solved.

[0056] The application solves the problems of fishy smell, color and peptide aggregation from the molecular level by the synergistic effect of amine capture nanoligand microspheres, tannic acid-chitosan complex and sodium alginate / chitooligosaccharide composite powder, and uses multiple chemical mechanisms to successfully optimize the performance of fish protein hydrolysate and prepare a high-efficiency amino acid peptide product without fishy smell, color and turbidity.

[0057] Compared with the prior art, the application has the following beneficial effects:

[0058] The application of fish protein products in functional drinks is limited due to the problem of fishy smell, which is mainly caused by amine small molecules such as oxidized trimethylamine. Therefore, the application uses amine capture nanoligand microspheres, forms a porous structure by cross-linking chitosan and sodium tripolyphosphate, and uses genipin to enhance the stability and selective adsorption capacity, thereby efficiently removing amine small molecules through hydrogen bonding and electrostatic interaction, and solving the problem of fishy smell.

[0059] The color of fish protein hydrolysate can be deepened by heme, polyphenol oxidation products and other pigment molecules, which affects the transparency. To solve this problem, the application introduces tannic acid-chitosan complex, realizes the selective removal of pigment molecules through the coordination of chitosan amino groups with the central metal ions of pigment molecules and the complexation of tannic acid phenolic hydroxyl groups with iron ions. At the same time, the hydrogen bonding and electrostatic interaction between tannic acid and chitosan enhance the capture capacity, and the sedimentation performance of the complex improves the separation efficiency of pigments, thereby effectively improving the color of the hydrolysate.

[0060] The medium and high molecular weight peptide segments in fish protein hydrolysate are prone to aggregation due to hydrophobic interaction, electrostatic interaction or pH change, which leads to turbidity or flocculation, affecting the transparency and stability. Therefore, the application introduces a sodium alginate and chitooligosaccharide composite system, provides electrostatic repulsion through the ionized carboxyl groups of sodium alginate, forms hydrogen bonds and hydrophobic interactions through the amino groups of chitooligosaccharide, and jointly constructs a stable supramolecular network to wrap and disperse peptide molecules and prevent aggregation. At the same time, calcium chloride enhances the gelation performance of sodium alginate, further improving the stability of the composite powder, thereby effectively solving the turbidity problem of the hydrolysate.

[0061] The application solves the problems of fishy smell, color and peptide aggregation from the molecular level by the synergistic effect of amine capture nanoligand microspheres, tannic acid-chitosan complex and sodium alginate / chitooligosaccharide composite powder, and uses multiple chemical mechanisms to successfully optimize the performance of fish protein hydrolysate and prepare a high-efficiency amino acid peptide product without fishy smell, color and turbidity. DETAILED DESCRIPTION

[0062] The technical solutions of the present application will be described in detail below with specific examples. The examples described herein are specific embodiments of the present application, which are used to illustrate the concept of the present application; all the descriptions are explanatory and exemplary, and should not be understood as limiting the embodiments of the present application and the protection scope of the present application. In addition to the examples described herein, those skilled in the art can also employ other technical solutions that are obvious based on the content disclosed in the claims and the description of the present application, which include technical solutions that employ any obvious substitutions and modifications to the examples described herein.

[0063] The chemical reagents used in the examples and comparative examples of the present application are all commercially available without further purification or treatment.

[0064] Example 1

[0065] The present example provides a high-efficiency amino acid peptide prepared from hydrolyzed fish protein and a preparation method thereof, and the preparation method of the high-efficiency amino acid peptide prepared from hydrolyzed fish protein specifically comprises the following steps:

[0066] The fish meat without head and bone was mixed with deionized water at a mass ratio of 1:4 to obtain fish meat slurry; the fish meat slurry was heated to 48℃ and the pH was adjusted to 6.5 to obtain a pretreated enzymatic hydrolysate, and then a neutral protease was added in an amount of 1.8% of the mass of the pretreated enzymatic hydrolysate to obtain reaction liquid A, which was stirred at a rotation speed of 100 rpm for 1 h to obtain reaction liquid B, and an amine capture nano-ligand microsphere was added in an amount of 0.8% of the mass of the pretreated enzymatic hydrolysate within 10 min after the start of the stirring reaction of reaction liquid A; then the temperature was raised to 88℃ for 12 min and then cooled to 47℃ to obtain reaction liquid C, a tannic acid-chitosan complex was added in an amount of 0.5% of the mass of the pretreated enzymatic hydrolysate and stirring was continued for 40 min to obtain reaction liquid D, and then sodium alginate / chitooligosaccharide complex powder was added in an amount of 0.4% of the mass of the pretreated enzymatic hydrolysate and uniformly dispersed to obtain reaction liquid E, and then centrifugation, vacuum concentration and freeze-drying were performed to obtain the high-efficiency amino acid peptide prepared from hydrolyzed fish protein.

[0067] The preparation method of the amine capture nano-ligand microsphere is as follows:

[0068] Chitosan was added to an ice acetic acid solution with a concentration of 0.7% to obtain a chitosan dispersion solution with a mass fraction of 1.5wt.%; a sodium tripolyphosphate solution with a mass fraction of 1.8wt.% and a genipin dispersion solution with a mass fraction of 0.15wt.% were prepared respectively, and the chitosan dispersion solution was added dropwise into the sodium tripolyphosphate solution at 33℃, wherein the mass ratio of chitosan to sodium tripolyphosphate was 7:1, and the first mixed solution was obtained by continuously stirring at a rotation speed of 300 rpm, and then the genipin dispersion solution was added dropwise and stirring was continued for 2 h to obtain the second mixed solution, wherein the mass ratio of genipin to sodium tripolyphosphate was 1:3, and the amine capture nano-ligand microspheres were obtained by centrifugation, washing and drying.

[0069] The preparation method of the tannic acid-chitosan complex is as follows:

[0070] A tannic acid dispersion solution with a mass fraction of 2.4 wt.% is prepared, and a tannic acid solution is obtained by adjusting the pH to 5; a chitosan dispersion solution with a mass fraction of 1.8 wt.% is prepared; the tannic acid solution is added dropwise into the chitosan dispersion solution, the mass ratio of tannic acid to chitosan being 1:1, and a complexing reaction solution is obtained by stirring for 50 min; centrifugation, washing and drying are performed to obtain the tannic acid-chitosan complex.

[0071] The preparation method of the sodium alginate / chitooligosaccharide complex powder is as follows:

[0072] A pre-sodium alginate solution with a mass fraction of 2.7 wt.% is prepared, and a sodium alginate solution is obtained by adjusting the pH to 6.5; a chitooligosaccharide solution with a mass fraction of 4 wt.% is prepared; the sodium alginate solution and the chitooligosaccharide solution are mixed at a volume ratio of 7:3 to obtain a mixed reaction solution, and stirring is performed at a rotation speed of 70 rpm for 70 min; a calcium chloride solution with a mass fraction of 0.04 wt.% is added, the mass ratio of calcium chloride to sodium alginate being 0.15:1, and uniform stirring is continued to obtain a pretreatment reaction solution, and freeze-drying is performed to obtain the sodium alginate / chitooligosaccharide complex powder.

[0073] Example 2

[0074] The present embodiment provides a high-efficiency amino acid peptide prepared from hydrolyzed fish protein and a preparation method thereof, and the preparation method of the high-efficiency amino acid peptide prepared from hydrolyzed fish protein specifically comprises the following steps:

[0075] The headless and boneless fish meat is mixed with deionized water at a mass ratio of 1:3 to obtain fish meat slurry; the fish meat slurry is heated to 47℃, and the pH is adjusted to 7 to obtain a pretreatment enzymolysis solution; a neutral protease with a dosage of 1% of the mass of the pretreatment enzymolysis solution is added to obtain reaction liquid A; stirring is performed at a rotation speed of 120 rpm for 2 h to obtain reaction liquid B; and the neutral protease with a dosage of 0.7% of the mass of the pretreatment enzymolysis solution is added within 15 min after the start of stirring of the reaction liquid A; then the temperature is raised to 80℃ for 13 min and then cooled to 40℃ to obtain reaction liquid C; the tannic acid-chitosan complex with a dosage of 0.57% of the mass of the pretreatment enzymolysis solution is added and stirring is continued for 50 min to obtain reaction liquid D; the sodium alginate / chitooligosaccharide complex powder with a dosage of 0.3% of the mass of the pretreatment enzymolysis solution is added and uniformly dispersed to obtain reaction liquid E; and centrifugation, vacuum concentration and freeze-drying are performed to obtain the high-efficiency amino acid peptide prepared from hydrolyzed fish protein.

[0076] The preparation method of the amine capture nanoligand microspheres is as follows:

[0077] Chitosan was added into 0.5% ice acetic acid solution to obtain a chitosan dispersion solution with a mass fraction of 1wt.%; a 1wt.% sodium tripolyphosphate solution and a 0.18wt.% genipin dispersion solution were respectively prepared, the chitosan dispersion solution was dropped into the sodium tripolyphosphate solution at 30℃, the mass ratio of chitosan to sodium tripolyphosphate was 6:1, and a first mixed solution was obtained by continuously stirring at a speed of 350rpm, the genipin dispersion solution was dropped into the first mixed solution and continuously stirred for 2.6h to obtain a second mixed solution, the mass ratio of genipin to sodium tripolyphosphate was 1:2, and amine-capturing nano-ligand microspheres were obtained by centrifugation, washing and drying;

[0078] The preparation method of the tannic acid-chitosan complex is as follows:

[0079] A 1.8wt.% tannic acid dispersion solution was prepared, and a tannic acid solution was obtained by adjusting the pH to 5.5; a 1.6wt.% chitosan dispersion solution was prepared; the tannic acid solution was dropped into the chitosan dispersion solution, the mass ratio of tannic acid to chitosan was 1.1:1, and a complexation reaction solution was obtained by stirring for 55min, and a tannic acid-chitosan complex was obtained by centrifugation, washing and drying;

[0080] The preparation method of the sodium alginate / chitooligosaccharide complex powder is as follows:

[0081] A 2.6wt.% pre-sodium alginate solution was prepared, and a sodium alginate solution was obtained by adjusting the pH to 6.8; a 4.6wt.% chitooligosaccharide solution was prepared; the sodium alginate solution and the chitooligosaccharide solution were mixed at a volume ratio of 6:4 to obtain a mixed reaction solution, and the mixed reaction solution was stirred at a speed of 50rpm for 74min, a 0.03wt.% calcium chloride solution was added, the mass ratio of calcium chloride to sodium alginate was 0.1:1, and the pretreatment reaction solution was uniformly stirred to obtain a pretreatment reaction solution, and the sodium alginate / chitooligosaccharide complex powder was obtained by freeze-drying.

[0082] Example 3

[0083] The present embodiment provides a high-efficiency amino acid peptide prepared by hydrolyzed fish protein and a preparation method thereof, and the preparation method of the high-efficiency amino acid peptide prepared by hydrolyzed fish protein specifically comprises the following steps:

[0084] The headless and boneless fish meat is mixed with deionized water at a mass ratio of 1:5 to obtain fish meat slurry; the fish meat slurry is heated to 45 DEG C and the pH is adjusted to 7.2 to obtain a pretreated enzymatic hydrolysis liquid, a neutral protease is added in an amount of 1.5% of the mass of the pretreated enzymatic hydrolysis liquid to obtain a reaction liquid A, and the reaction liquid A is stirred at a rotation speed of 130 rpm for 1.8 h to obtain a reaction liquid B, and the amine capture nano-ligand microspheres are added in an amount of 0.5% of the mass of the pretreated enzymatic hydrolysis liquid within 18 min after the start of the stirring reaction of the reaction liquid A; then the temperature is increased to 90 DEG C for 10 min and then cooled to 50 DEG C to obtain a reaction liquid C, a tannic acid-chitosan complex is added in an amount of 0.4% of the mass of the pretreated enzymatic hydrolysis liquid and continues to be stirred for 55 min to obtain a reaction liquid D, and a sodium alginate / chitooligosaccharide composite powder is added in an amount of 0.42% of the mass of the pretreated enzymatic hydrolysis liquid and is uniformly dispersed to obtain a reaction liquid E, and the reaction liquid E is centrifuged, vacuum concentrated and freeze-dried to obtain a high-efficiency amino acid peptide prepared from hydrolyzed fish protein.

[0085] The preparation method of the amine capture nano-ligand microspheres is as follows:

[0086] Chitosan is added to an ice acetic acid solution with a concentration of 1% to obtain a chitosan dispersion liquid with a mass fraction of 2 wt.%; a sodium tripolyphosphate solution with a mass fraction of 1.5 wt.% and a genipin dispersion liquid with a mass fraction of 0.1 wt.% are respectively prepared, the chitosan dispersion liquid is dropped into the sodium tripolyphosphate solution at 25 DEG C, wherein the mass ratio of chitosan to sodium tripolyphosphate is 5:1, and the first mixed liquid is obtained by continuously stirring at a rotation speed of 200 rpm, the genipin dispersion liquid is dropped into the first mixed liquid and continues to be stirred for 2.7 h to obtain the second mixed liquid, wherein the mass ratio of genipin to sodium tripolyphosphate is 1:4, and the amine capture nano-ligand microspheres are obtained by centrifugation, washing and drying;

[0087] The preparation method of the tannic acid-chitosan complex is as follows:

[0088] A tannic acid dispersion liquid with a mass fraction of 1 wt.% is prepared, and a tannic acid solution is obtained by adjusting the pH to 5.8; a chitosan dispersion liquid with a mass fraction of 1 wt.% is prepared; the tannic acid solution is dropped into the chitosan dispersion liquid, wherein the mass ratio of tannic acid to chitosan is 0.8:1, and a complexation reaction liquid is obtained by stirring for 58 min, and the tannic acid-chitosan complex is obtained by centrifugation, washing and drying;

[0089] The preparation method of the sodium alginate / chitooligosaccharide composite powder is as follows:

[0090] A 2wt.% sodium alginate solution was prepared, and the pH was adjusted to 6.7 to obtain a sodium alginate solution; a 3wt.% chitosan oligosaccharide solution was prepared; the sodium alginate solution and the chitosan oligosaccharide solution were mixed at a volume ratio of 7.6:2.4 to obtain a mixed reaction solution, which was stirred at a rotation speed of 80 rpm for 60 min, and then a 0.01wt.% calcium chloride solution was added, wherein the mass ratio of calcium chloride to sodium alginate was 0.17:1, and the mixture was continuously stirred to obtain a pretreated reaction solution, which was freeze-dried to obtain a sodium alginate / chitosan oligosaccharide composite powder.

[0091] Example 4

[0092] The present embodiment provides a hydrolyzed fish protein prepared high-efficiency amino acid peptide and a preparation method thereof. The preparation method of the hydrolyzed fish protein prepared high-efficiency amino acid peptide specifically comprises the following steps:

[0093] The headless and boneless fish meat was mixed with deionized water at a mass ratio of 1:4.6 to obtain fish meat slurry; the fish meat slurry was heated to 50℃, and the pH was adjusted to 7.5 to obtain a pretreated enzymatic hydrolysis solution; a neutral protease was added in an amount of 2% of the mass of the pretreated enzymatic hydrolysis solution to obtain reaction solution A; the reaction solution A was stirred at a rotation speed of 150 rpm for 1.5 h to obtain reaction solution B; and an amine capture nano-ligand microsphere was added in an amount of 1.0% of the mass of the pretreated enzymatic hydrolysis solution within 20 min after the start of the stirring of the reaction solution A; then the temperature was raised to 85℃ for 15 min and then cooled to 44℃ to obtain reaction solution C; a tannic acid-chitosan composite was added in an amount of 0.6% of the mass of the pretreated enzymatic hydrolysis solution and continuously stirred for 60 min to obtain reaction solution D; the reaction solution D was centrifuged, and a sodium alginate / chitosan oligosaccharide composite powder was added in an amount of 0.5% of the mass of the pretreated enzymatic hydrolysis solution and uniformly dispersed to obtain reaction solution E; the reaction solution E was centrifuged, vacuum concentrated, and freeze-dried to obtain a hydrolyzed fish protein prepared high-efficiency amino acid peptide.

[0094] The preparation method of the amine capture nano-ligand microsphere is as follows:

[0095] Chitosan was added to a 0.8% glacial acetic acid solution to obtain a 1.6wt.% chitosan dispersion; a 2wt.% sodium tripolyphosphate solution and a 0.2wt.% genipin dispersion were prepared, respectively; the chitosan dispersion was added dropwise into the sodium tripolyphosphate solution at 35℃, wherein the mass ratio of chitosan to sodium tripolyphosphate was 8:1, and the mixture was continuously stirred at a rotation speed of 400 rpm to obtain a first mixed solution; the genipin dispersion was added dropwise into the first mixed solution and continuously stirred for 3 h to obtain a second mixed solution, wherein the mass ratio of genipin to sodium tripolyphosphate was 1:3.5; the second mixed solution was centrifuged, washed, and dried to obtain amine capture nano-ligand microspheres;

[0096] The preparation method of the tannic acid-chitosan composite is as follows:

[0097] A tannic acid dispersion solution with a mass fraction of 3wt.% was prepared, and the pH was adjusted to 6 to obtain a tannic acid solution; a chitosan dispersion solution with a mass fraction of 2wt.% was prepared; the tannic acid solution was added dropwise into the chitosan dispersion solution, and the mass ratio of tannic acid to chitosan was 1.2:1, and the reaction was stirred for 60min to obtain a complex reaction solution, which was centrifuged, washed and dried to obtain a tannic acid-chitosan complex;

[0098] The preparation method of the sodium alginate / chitooligosaccharide composite powder is as follows:

[0099] A pre-sodium alginate solution with a mass fraction of 3wt.% was prepared, and the pH was adjusted to 7 to obtain a sodium alginate solution; a chitooligosaccharide solution with a mass fraction of 5wt.% was prepared; the sodium alginate solution and the chitooligosaccharide solution were mixed at a volume ratio of 8:2 to obtain a mixed reaction solution, which was stirred at a rotation speed of 100rpm for 80min, and a calcium chloride solution with a mass fraction of 0.05wt.% was added, and the mass ratio of calcium chloride to sodium alginate was 0.2:1, and the stirring was continued to obtain a pretreatment reaction solution, which was freeze-dried to obtain a sodium alginate / chitooligosaccharide composite powder.

[0100] Comparative Example 1

[0101] This comparative example provides a high-efficiency amino acid peptide prepared by hydrolyzing fish protein, which is different from Example 1 in that no amine capture nano-ligand microspheres are added, and other operation steps and process parameters are exactly the same as those of Example 1.

[0102] Comparative Example 2

[0103] This comparative example provides a high-efficiency amino acid peptide prepared by hydrolyzing fish protein, which is different from Example 1 in that no tannic acid-chitosan complex is added, and other operation steps and process parameters are exactly the same as those of Example 1.

[0104] Comparative Example 3

[0105] This comparative example provides a high-efficiency amino acid peptide prepared by hydrolyzing fish protein, which is different from Example 1 in that no sodium alginate / chitooligosaccharide composite powder is added, and other operation steps and process parameters are exactly the same as those of Example 1.

[0106] The high-efficiency amino acid peptides prepared by hydrolyzing fish protein in Examples 1-4 and Comparative Examples 1-3 are tested for performance, and the specific process is as follows:

[0107] A group of 10 professional sensory evaluation personnel are organized, and a scoring method is used to evaluate the fishy smell intensity of the samples, with a score range of 0 (no fishy smell) to 5 (strong fishy smell), and the average score of each sample is taken;

[0108] The absorbance of reaction liquid C and reaction liquid D in each example or comparative example is tested by spectrophotometry, and the pigment removal rate is calculated:

[0109] Color removal rate = (absorbance of reaction solution C - absorbance of reaction solution D) / absorbance of reaction solution C x 100%;

[0110] The light transmittance of reaction solution D and reaction solution E in each example or comparative example was tested using a spectrophotometer to characterize the degree of aggregation of the peptide molecules;

[0111] The test results are shown in Table 1.

[0112] Table 1: Performance test results of hydrolyzed fish protein prepared high-efficiency amino acid peptides of Examples 1-4 and Comparative Examples 1-3

[0113]

[0114] From the test results of Example 1 and Comparative Example 1, it can be seen that without adding amine-capturing nano-ligand microspheres, volatile amine molecules are not effectively removed, and the fishy smell is significantly enhanced; the tannic acid-chitosan complex can still effectively remove pigment molecules, and the effect of sodium alginate / chitooligosaccharide composite powder on inhibiting peptide aggregation is not affected, so the effects on color removal rate and light transmittance are small.

[0115] From the test results of Example 1 and Comparative Example 2, it can be seen that without adding tannic acid-chitosan complex, hematin, iron porphyrin, polyphenol oxidation products and other pigment molecules are not effectively removed, and only a small amount of sediment can be removed by centrifugation, resulting in a significant decrease in color removal rate; the remaining pigment molecules will cause the liquid color to deepen, affecting the transmission of light, but the inhibitory effect of sodium alginate / chitooligosaccharide composite powder on peptide segment aggregation is still effective, so the light transmittance remains at a medium level; the effect on fishy smell is small.

[0116] From the test results of Example 1 and Comparative Example 3, it can be seen that without adding sodium alginate / chitooligosaccharide composite powder, peptide segments aggregate due to hydrophobic interaction, electrostatic interaction or pH change, resulting in increased turbidity and a significant decrease in light transmittance; amine-capturing nano-ligand microspheres can still effectively remove fishy smell molecules, and the effect of tannic acid-chitosan complex is not changed, so the changes in fishy smell sensory score and color removal rate are small.

[0117] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed by the present application can be easily thought of by those skilled in the art, and all fall within the protection scope and disclosure scope of the present application.

Claims

1. A method for preparing high-efficiency amino acid peptides prepared by hydrolyzing fish protein, characterized in that: The preparation method comprises: The headless and boneless fish meat is mixed with deionized water and minced to obtain fish meat slurry; the fish meat slurry is heated and the pH is adjusted to obtain a pretreated enzymatic hydrolyzate, a neutral protease is added to obtain a reaction solution A, and amine-captured nano-ligand microspheres are added while stirring the reaction to obtain a reaction solution B; the temperature is then increased and maintained at a constant temperature, and then cooled to obtain a reaction solution C, a tannic acid-chitosan complex is added and continued to be stirred, and the reaction solution is centrifuged to obtain a reaction solution D, a sodium alginate / chitosan oligosaccharide composite powder is added and uniformly dispersed to obtain a reaction solution E, and the reaction solution is centrifuged, vacuum concentrated, and freeze-dried to obtain a high-efficiency amino acid peptide prepared from the hydrolyzed fish protein.

2. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 1, characterized in that: The feeding amount of the neutral protease is 1%-2% of the mass of the pre-treated enzymatic hydrolysate; The feeding amount of the amine-captured nano-ligand microspheres is 0.5%-1.0% of the mass of the pre-treated enzymatic hydrolysate.

3. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 1, characterized in that: The reaction solution B is heated to 80-90°C; After the reaction solution B is heated, the constant temperature is maintained for 10-15 minutes; The feeding amount of the tannic acid-chitosan complex is 0.4%-0.6% of the mass of the pre-treated enzymatic hydrolysate; The feeding amount of the sodium alginate / chitosan oligosaccharide composite powder is 0.3%-0.5% of the mass of the pretreated enzymatic hydrolysate.

4. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 1, characterized in that: The preparation method of the amine-captured nano-ligand microspheres is as follows: Chitosan is added to a glacial acetic acid solution to obtain a chitosan dispersion; a sodium tripolyphosphate solution and a genipin dispersion are prepared respectively, the chitosan dispersion is dropped into the sodium tripolyphosphate solution and continuously stirred to obtain a first mixed solution, the genipin dispersion is dropped into the solution and continuously stirred to obtain a second mixed solution, and the solution is centrifuged, washed, and dried to obtain amine-captured nano-ligand microspheres.

5. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 4, characterized in that: In the preparation method of the amine-captured nano-ligand microspheres: The mass ratio of chitosan to sodium tripolyphosphate in the first mixed solution is 5-8:1; The mass ratio of genipin to sodium tripolyphosphate in the second mixed solution is 1:2-4.

6. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 1, characterized in that: The preparation method of the tannic acid-chitosan complex is as follows: Prepare a tannic acid dispersion, adjust the pH to obtain a tannic acid solution; prepare a chitosan dispersion; dropwise add the tannic acid solution into the chitosan dispersion, stir to react to obtain a complexing reaction solution, centrifuge, wash, and dry to obtain a tannic acid-chitosan complex.

7. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 6, characterized in that: In the preparation method of the tannic acid-chitosan complex: The mass fraction of the tannic acid dispersion is 1wt.%-3wt.%; The mass fraction of the chitosan dispersion is 1wt.%-2wt.%; The mass ratio of the tannic acid to chitosan is 0.8-1.2:

1.

8. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 1, characterized in that: The preparation method of the sodium alginate / chitosan oligosaccharide composite powder is as follows: preparing a pre-sodium alginate solution and adjusting the pH to obtain a sodium alginate solution; preparing a chitosan oligosaccharide solution; The sodium alginate solution and the chitosan oligosaccharide solution are mixed to obtain a mixed reaction solution, the mixture is stirred for reaction, a calcium chloride solution is added and the mixture is stirred evenly to obtain a pretreatment reaction solution, and the mixture is freeze-dried to obtain a sodium alginate / chitosan oligosaccharide composite powder.

9. The method for preparing a high-efficiency amino acid peptide prepared by hydrolyzing fish protein according to claim 8, characterized in that: In the preparation method of the sodium alginate / chitosan oligosaccharide composite powder: The volume ratio of the sodium alginate solution to the chitosan oligosaccharide solution is 6:4-8:2; The mass ratio of the calcium chloride to the sodium alginate is 0.1-0.2:

1.

10. A high-efficiency amino acid peptide prepared by hydrolyzing fish protein, characterized in that: Prepared according to the preparation method according to any one of claims 1 to 9.

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