Preparation method of animal blood cell polypeptide powder

Abstract

The invention relates to the technical field of polypeptide preparation, and particularly discloses a preparation method of animal blood cell polypeptide powder. The invention relates to an animal blood cell polypeptide powder preparation method, which comprises: adding trisodium citrate to fresh animal blood, stirring for 10-30 min, adding anthocyanidin and polylysine, uniformly stirring, placing in an environment with a temperature of-10--20 DEG C, carrying out thermal insulation for 1-2 h, heating to a room temperature, carrying out homogenization treatment for 1-5 min, centrifuging, and removing the supernatant to obtain an animal blood cell liquid; adding the animal blood cell liquid and the rare earth lanthanum chitosamine chelate salt into the glycine-sodium hydroxide buffer solution, stirring at 40-50 DEG C for 10-30 minutes, adding the compound protease, and continuously stirring for 10-20 hours to obtain enzymatic hydrolysate; and adjusting the pH value of the enzymatic hydrolysate to 5-6, heating to 90-100 DEG C, preserving heat for 5-10 minutes, cooling to room temperature, centrifuging for 5-10 minutes, taking supernate, and carrying out low-temperature spray drying.

Description

Technical Field

[0001] The present invention relates to the technical field of polypeptide preparation, in particular to a method for preparing animal blood cell polypeptide powder. Background Art

[0002] Animal blood contains a variety of nutrients, such as protein, amino acids, vitamins, sugars, lipids, mineral elements, etc., among which the protein content of fresh blood is as high as 22%, which is the largest animal polypeptide powder resource. At present, only 20% of animal blood is used in a centralized and reasonable manner, while the vast majority is discharged as waste, thus causing serious pollution to the environment. Therefore, it is crucial to reasonably utilize the blood of slaughtered animals and improve the centralized utilization rate.

[0003] Animal blood has a high potential nutritional value, but the current utilization of animal blood is still very insufficient. At present, the main research method is chemical treatment, which not only pollutes the environment, but also has poor stability and effect of the obtained polypeptide powder. With the development of the enzyme preparation industry, the cost of enzyme preparation products has gradually decreased, which has also promoted the use of enzymes in animal blood polypeptide powder. Due to different types of enzymes, the conditions for enzymatic hydrolysis of animal blood cells are different, and the enzymatic hydrolysis effects are also different.

[0004] CN110904177A discloses a pig blood polypeptide powder and its preparation method and application, which is prepared by the following steps: pre-treatment of pig blood to obtain blood cells; crushing and homogenizing blood cells to obtain blood cell lysate; enzymatic hydrolysis to obtain enzymatic hydrolysis solution; inactivation of enzymes to obtain product dilution; concentration to obtain product concentrate; sterile filtration of the product concentrate, freeze drying, crushing and packaging to obtain the final product. However, the product has poor stability, and the processing cost and production difficulty are relatively high, which is not conducive to practical application.

[0005] Therefore, in view of the above problems, how to provide a production process for animal blood cell polypeptide powder with good enzymatic hydrolysis effect, good stability and excellent antioxidant activity has become a technical problem that needs to be solved at present. Summary of the invention

[0006] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a method for preparing animal blood cell polypeptide powder.

[0007] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0008] S1. Add trisodium citrate to fresh animal blood and stir for 10-30 minutes, add anthocyanin and polylysine and stir evenly, place in a temperature of -10 to -20°C for 1-2 hours, warm to room temperature, homogenize for 1-5 minutes, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0009] S2, adding animal blood cell fluid and rare earth lanthanum chitosan chelate salt to glycine-sodium hydroxide buffer solution, stirring at 40-50° C. for 10-30 min, adding composite protease and continuing stirring for 10-20 h to obtain enzymatic solution;

[0010] S3. Adjust the pH value of the enzymatic hydrolysate to 5-6, raise the temperature to 90-100°C and keep it for 5-10 minutes, then cool it to room temperature, centrifuge it for 5-10 minutes, and take the supernatant for low-temperature spray drying.

[0011] Preferably, in S1, the fresh animal blood is one of chicken blood, duck blood, pig blood, cow blood and sheep blood.

[0012] Preferably, in S1, the mass ratio of fresh animal blood, trisodium citrate, anthocyanin and polylysine is 100:1-3:1-2:0.1-1.

[0013] Preferably, in S1, the speed of heating to room temperature is 1-2°C / min; and the homogenization speed is 8000-10000 r / min.

[0014] Preferably, in S2, the mass ratio of animal blood cell fluid, rare earth lanthanum chitosan chelate salt, glycine-sodium hydroxide buffer solution, and composite protease is 30-50:1-2:200-300:0.1-1.

[0015] Preferably, in S2, the concentration of the glycine-sodium hydroxide buffer solution is 0.01-0.02 mol / L, and its pH value is 9-9.6.

[0016] Preferably, in S2, the specific activity of the composite protease is 5000-8000 U / g.

[0017] Preferably, in S2, the composite protease comprises alkaline protease.

[0018] Preferably, in S2, the alkaline protease is at least one of baker's yeast alkaline protease, serine alkaline protease, Bacillus subtilis alkaline protease and streptomycin alkaline protease.

[0019] Preferably, in S3, the pH value of the enzymatic hydrolysis solution is adjusted to 5-6 using hydrochloric acid with a concentration of 1-2 mol / L.

[0020] Preferably, in S3, the centrifugal speed is 5000-8000 r / min.

[0021] Preferably, in S3, the low-temperature spray drying temperature is 40-50°C.

[0022] An animal blood cell polypeptide powder is prepared by adopting the animal blood cell polypeptide powder preparation method.

[0023] Beneficial effects:

[0024] The present invention freezes fresh animal blood to promote the lysis and fragmentation of a large number of blood cells, and then homogenizes the blood to achieve an excellent fragmentation effect. The compounding of anthocyanin and polylysine can effectively inhibit the oxidation and denaturation problems that occur during the freezing process, and can inhibit the damage of ice crystals to proteins, which can not only increase the protein content, but also effectively ensure the antioxidant activity of the polypeptide.

[0025] The present invention uses animal blood cell fluid and rare earth lanthanum chitosan chelate salt to form peptide segments with smaller molecular weights through compound protease hydrolysis. The polypeptide has uniform molecular weight distribution, good solubility, and excellent antioxidant activity. It is found through experiments that the animal blood cell polypeptide powder obtained by the present invention exhibits extremely strong DPPH free radical scavenging ability, which can reach 97.9%.

[0026] At the same time, the animal blood cell polypeptide powder obtained by the invention can also improve intestinal mucosal immunity, protect intestinal health, has high safety, no side effects, no bad flavor, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The figure is a comparison chart of the hydrolysis degree and crude protein content of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3.

[0028] Figure 2 The figure is a comparison chart of the percentage of peptide molecular weight in the animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3.

[0029] Figure 3 The chromaticity comparison diagram of the animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3 is shown.

[0030] Figure 4 The figure is a comparison chart of the DPPH free radical scavenging ability and superoxide anion scavenging ability of the animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3.

[0031] Figure 5 The figure is a comparison chart of the reducing power and metal ion chelating ability of the animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3. DETAILED DESCRIPTION

[0032] The present invention will be further explained below in conjunction with specific embodiments.

[0033] Example 1

[0034] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0035] S1. Add 10 g of trisodium citrate to 1000 g of chicken blood, stir at a speed of 3000 r / min for 10 min, add 10 g of anthocyanin and 1 g of polylysine and stir evenly, place in a temperature of -10 ° C. environment for 1 h, warm to room temperature at a speed of 1 ° C. / min, homogenize for 1 min at a homogenization speed of 8000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0036] S2, add 300g animal blood cell fluid and 10g rare earth lanthanum chitosan chelate salt to 2000g glycine-sodium hydroxide buffer solution with pH = 9 and concentration of 0.01mol / L, stir at a temperature of 40°C for 10min, stirring speed of 50r / min, add 1g composite protease (composed of papain and Bacillus subtilis alkaline protease) with a specific activity of 5000U / g, continue stirring for 10h, and obtain enzymolysis solution;

[0037] S3. Use 1 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5, raise the temperature to 90°C and keep it for 5 minutes, then cool it to room temperature, centrifuge it at 5000 r / min for 5 minutes, take the supernatant, and spray dry it at 40°C.

[0038] Example 2

[0039] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0040] S1. Add 30 g of trisodium citrate to 1000 g of sheep blood, stir at a speed of 4000 r / min for 30 min, add 20 g of anthocyanin and 10 g of polylysine and stir evenly, place in a -20°C environment for 2 h, warm to room temperature at a speed of 2°C / min, homogenize for 5 min at a homogenization speed of 10000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0041] S2, add 500g animal blood cell fluid and 20g rare earth lanthanum chitosan chelate salt to 3000g glycine-sodium hydroxide buffer solution with pH = 9.6 and a concentration of 0.02mol / L, stir at a temperature of 50°C for 30min, a stirring speed of 100r / min, add 10g composite protease (composed of papain and streptomycin alkaline protease) with a specific activity of 8000U / g, continue stirring for 20h, and obtain an enzymolysis solution;

[0042] S3. Use 2 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 6, raise the temperature to 100°C and keep it for 10 min, then cool it to room temperature, centrifuge it at 8000 r / min for 10 min, take the supernatant, and spray dry it at 50°C.

[0043] Example 3

[0044] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0045] S1. Add 15 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3700 r / min for 15 min, add 17 g of anthocyanin and 2 g of polylysine and stir evenly, place in a -17 ° C environment for 80 min, warm to room temperature at a speed of 1.8 ° C / min, homogenize for 2 min at a homogenization speed of 9500 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0046] S2, add 350g animal blood cell fluid and 17g rare earth lanthanum chitosan chelate salt to 2200g glycine-sodium hydroxide buffer solution with pH = 9.3 and a concentration of 0.012mol / L, stir at a temperature of 48°C for 15min, stirring at a speed of 90r / min, add 3g of composite protease (composed of streptomycin alkaline protease and serine alkaline protease) with a specific activity of 7000U / g, continue stirring for 13h, and obtain an enzymolysis solution;

[0047] S3. Use 1.8 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5.5, raise the temperature to 92°C and keep it for 9 minutes, then cool it to room temperature, centrifuge it at 6000 r / min for 9 minutes, take the supernatant, and spray dry it at 42°C.

[0048] Example 4

[0049] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0050] S1. Add 25 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3300 r / min for 25 min, add 13 g of anthocyanin and 8 g of polylysine and stir evenly, place in a -13 ° C environment for 100 min, warm to room temperature at a speed of 1.2 ° C / min, homogenize for 4 min at a homogenization speed of 8500 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0051] S2, add 450g animal blood cell fluid and 13g rare earth lanthanum chitosan chelate salt to 2800g glycine-sodium hydroxide buffer solution with pH = 9.3 and a concentration of 0.018mol / L, stir at a temperature of 42°C for 25min, a stirring speed of 70r / min, add 7g of a composite protease with a specific activity of 6000U / g (composed of baker's yeast alkaline protease and serine alkaline protease), continue stirring for 17h, and obtain an enzymolyzate;

[0052] S3. Use 1.2 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5.5, raise the temperature to 98°C and keep it for 7 minutes, then cool it to room temperature, centrifuge it at 7000 r / min for 7 minutes, take the supernatant, and spray dry it at 48°C.

[0053] Example 5

[0054] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0055] S1. Add 20 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3500 r / min for 20 min, add 15 g of anthocyanin and 5 g of polylysine and stir evenly, place in a -15 ° C environment for 90 min, warm to room temperature at a speed of 1.5 ° C / min, homogenize for 3 min at a homogenization speed of 9000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0056] S2, add 400g animal blood cell fluid and 15g rare earth lanthanum chitosan chelate salt to 2400g glycine-sodium hydroxide buffer solution with pH = 9-9.6 and a concentration of 0.015mol / L, stir at a temperature of 45°C for 20min, a stirring speed of 80r / min, add 5g of a composite protease with a specific activity of 6500U / g (composed of baker's yeast alkaline protease and Bacillus subtilis alkaline protease), continue stirring for 15h, and obtain an enzymolyzate;

[0057] S3. Use 1.5 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5-6, raise the temperature to 95°C and keep it for 8 minutes, then cool it to room temperature, centrifuge it at 6500 r / min for 8 minutes, take the supernatant, and spray dry it at 45°C.

[0058] Comparative Example 1

[0059] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0060] S1. Add 20 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3500 r / min for 20 min, add 15 g of anthocyanin and stir evenly, place in a temperature of -15 ° C. environment for 90 min, warm to room temperature at a speed of 1.5 ° C. / min, homogenize for 3 min at a homogenization speed of 9000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0061] S2, add 400g animal blood cell fluid and 15g rare earth lanthanum chitosan chelate salt to 2400g glycine-sodium hydroxide buffer solution with pH = 9-9.6 and a concentration of 0.015mol / L, stir at a temperature of 45°C for 20min, a stirring speed of 80r / min, add 5g of a composite protease with a specific activity of 6500U / g (composed of baker's yeast alkaline protease and Bacillus subtilis alkaline protease), continue stirring for 15h, and obtain an enzymolyzate;

[0062] S3. Use 1.5 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5-6, raise the temperature to 95°C and keep it for 8 minutes, then cool it to room temperature, centrifuge it at 6500 r / min for 8 minutes, take the supernatant, and spray dry it at 45°C.

[0063] Comparative Example 2

[0064] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0065] S1. Add 20 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3500 r / min for 20 min, add 15 g of anthocyanin and 5 g of polylysine and stir evenly, place in a -15 ° C environment for 90 min, warm to room temperature at a speed of 1.5 ° C / min, homogenize for 3 min at a homogenization speed of 9000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0066] S2, add 400g of animal blood cell fluid to 2400g of glycine-sodium hydroxide buffer solution with pH=9-9.6 and concentration of 0.015mol / L, stir at a temperature of 45°C for 20min, stirring speed of 80r / min, add 5g of composite protease with specific activity of 6500U / g (composed of baker's yeast alkaline protease and Bacillus subtilis alkaline protease), continue stirring for 15h, and obtain enzymolysis solution;

[0067] S3. Use 1.5 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5-6, raise the temperature to 95°C and keep it for 8 minutes, then cool it to room temperature, centrifuge it at 6500 r / min for 8 minutes, take the supernatant, and spray dry it at 45°C.

[0068] Comparative Example 3

[0069] A method for preparing animal blood cell polypeptide powder comprises the following steps:

[0070] S1. Add 20 g of trisodium citrate to 1000 g of pig blood, stir at a speed of 3500 r / min for 20 min, add 15 g of anthocyanin and 5 g of polylysine and stir evenly, place in a -15 ° C environment for 90 min, warm to room temperature at a speed of 1.5 ° C / min, homogenize for 3 min at a homogenization speed of 9000 r / min, centrifuge, remove the supernatant, and obtain animal blood cell fluid;

[0071] S2, add 400g animal blood cell fluid and 15g rare earth lanthanum chitosan chelate salt to 2400g glycine-sodium hydroxide buffer solution with pH = 9-9.6 and a concentration of 0.015mol / L, stir at a temperature of 45°C for 20min, stirring at a speed of 80r / min, add 5g of composite protease (composed of bromelain and trypsin) with a specific activity of 6500U / g, continue stirring for 15h, and obtain an enzymolysis solution;

[0072] S3. Use 1.5 mol / L hydrochloric acid to adjust the pH value of the enzymatic hydrolyzate to 5-6, raise the temperature to 95°C and keep it for 8 minutes, then cool it to room temperature, centrifuge it at 6500 r / min for 8 minutes, take the supernatant, and spray dry it at 45°C.

[0073] The degree of hydrolysis (DH) of a protein refers to the percentage of peptide bonds that are cleaved during the protein hydrolysis reaction. The present invention uses the o-phthalaldehyde (OPA) method to determine the degree of hydrolysis. The animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3 is diluted with water by the same multiple, 0.4 mL of the diluted solution of each group is taken, 3 mL of OPA reagent is added, and the reaction is accurately reacted for 2 minutes, and the absorbance value is measured at 340 nm.

[0074] The crude protein content of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined by Kjeldahl nitrogen determination.

[0075] like Figure 1 As shown, the hydrolysis degree and crude protein content of the animal blood polypeptide powder obtained in Example 5 are the highest, which are better than those in Comparative Examples 1-3 (P < 0.05), which proves that the method of the present invention can effectively hydrolyze the protein in fresh animal blood.

[0076] The molecular weight distribution of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined by high performance liquid chromatography. The injection volume of the prepared polypeptide samples and standards (molecular weight of 6500Da, 13700Da, 43000Da) was 100 μL, the detection time was 50 min, and the percentage of peptide molecular weight was calculated based on the peak value and peak area.

[0077] like Figure 2As shown, in the animal blood polypeptide powder obtained in Example 5, the molecular weight less than 1 kDa accounts for more than 60%, which is better than that of Comparative Examples 1-3 (P<0.05). It is confirmed that the method of the present invention is more beneficial to the production of small molecule peptides.

[0078] The chromaticity of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was measured using a Minolta CR-410 colorimeter. The L value represents black-white (brightness), and the larger the value, the whiter (brighter); the a value represents green-red, and the larger the value, the redder; the b value represents blue-yellow, and the larger the value, the yellower; WI represents whiteness, WI = 100-[2×(100-L) 2 +a 2 +b 2 ] 0.5 ; C (chroma) represents chromaticity, h (hue) represents hue, and the higher the value, the purer the color.

[0079] like Figure 3 As shown, the L value of the animal blood polypeptide powder obtained in Example 5 is slightly higher than that of Comparative Examples 1-3, but there is no significant difference (P>0.05); the WI, C and h of the animal blood polypeptide powder obtained in Example 5 are the highest, which are better than Comparative Examples 1-3 (P<0.05), which proves that the method of the present invention is more conducive to decolorization, the product tends to be purer, and it helps to maintain the stability of the product during storage.

[0080] The DPPH free radical scavenging ability of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined. The specific operation was as follows: 1.5 mL of 2 mg / mL animal blood polypeptide powder solution of each group was mixed with 1.5 mL DPPH (1.0 mM), reacted at room temperature in the dark for 30 minutes, and the absorbance was measured at 517 nm.

[0081] The superoxide anion scavenging ability of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined. The specific operation was as follows: 0.1 mL of the 2 mg / mL aqueous solution of each group of animal blood polypeptide powder was added with 2.8 mL of Tris-HCl-EDTA (pH=8.2) buffer, and after being incubated in a 25°C water bath for 10 min, 0.1 mL of 3.0 mM pyrogallol solution was added, and the mixture was quickly mixed. The absorbance was measured at 325 nm every 30 s for 5 min.

[0082] Superoxide anion scavenging capacity (%) = (V 对照 -V 试样 )÷V 对照 ×100%

[0083] Among them, V 对照 is the self-oxidation rate of pyrogallol in the control group (△A / min), V 试样 is the oxidation rate of phthalate in each group (△A / min).

[0084] like Figure 4 As shown, the DPPH free radical scavenging ability and superoxide anion scavenging ability of the animal blood cell polypeptide powder obtained in Example 5 are both the highest, which are better than those of Comparative Examples 1-3 (P<0.05).

[0085] The reducing power of the animal blood polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined as follows: 1.0 mL of the sample was mixed with 1.0 mL of sodium phosphate solution with pH = 6.6 and 1.0 mL of 1% potassium ferricyanide, and incubated at 50°C for 20 min. 1.0 mL of 10% TCA solution was added, and centrifuged at 5000×g for 10 min. 2.0 mL of the supernatant was taken, mixed with 2.0 mL of deionized water and 0.4 mL of 0.1% ferric chloride, and allowed to stand at room temperature for 10 min, and the absorbance was measured at 700 nm.

[0086] The metal ion chelating ability of the animal blood cell polypeptide powder obtained in Example 5 and Comparative Examples 1-3 was determined by the following specific operation:

[0087] Add 100 μL of 20 μM ferrous chloride solution to 50 μL of sample, mix well, then add 100 μL of 0.5 mM ferrozine solution, shake vigorously, and measure the absorbance value A at 562 nm after 10 minutes of reaction. 试样 Take 1.0mL of deionized water to replace the sample and measure A 对照 EDTA was used as a positive control, and all measured values ​​were the average of three times.

[0088] Metal ion chelating capacity (%) = [(A 对照 -A 试样 ) / A 对照 ]×100%.

[0089] like Figure 5 As shown, the reducing power and metal ion chelating ability of the animal blood polypeptide powder obtained in Example 5 are both the strongest, which are better than those of Comparative Examples 1-3 (P<0.05).

[0090] The applicant believes that the reason for the above results is that the present invention freezes fresh animal blood to promote the lysis and fragmentation of blood cells, and then homogenizes the blood cells to achieve excellent fragmentation effect; and the compounding of anthocyanin and polylysine can effectively inhibit the oxidation and denaturation problems that occur during the freezing process, and can inhibit the damage of ice crystals to proteins, which can not only increase the protein content, but also effectively ensure the antioxidant activity of polypeptides. Animal blood cell fluid is compounded with rare earth lanthanum chitosan chelate salt, and the peptides with smaller molecular weight are formed by enzymatic hydrolysis with composite protease, and the molecular weight distribution of the polypeptides is uniform, the solubility is good, and the antioxidant activity is excellent.

[0091] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing animal blood cell polypeptide powder, characterized in that: The steps include: S1. Add trisodium citrate to fresh animal blood and stir for 10-30 minutes, add anthocyanin and polylysine and stir evenly, place in a temperature of -10 to -20°C for 1-2 hours, warm to room temperature, homogenize for 1-5 minutes, centrifuge, remove the supernatant, and obtain animal blood cell fluid; S2, adding animal blood cell fluid and rare earth lanthanum chitosan chelate salt to glycine-sodium hydroxide buffer solution, stirring at 40-50° C. for 10-30 min, adding composite protease and continuing stirring for 10-20 h to obtain enzymatic solution; S3. Adjust the pH value of the enzymatic hydrolysate to 5-6, raise the temperature to 90-100°C and keep it for 5-10 minutes, then cool it to room temperature, centrifuge it for 5-10 minutes, and take the supernatant for low-temperature spray drying.

2. The method for preparing animal blood polypeptide powder according to claim 1, characterized in that: In S1, the fresh animal blood is one of chicken blood, duck blood, pig blood, cow blood and sheep blood.

3. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S1, the mass ratio of fresh animal blood, trisodium citrate, anthocyanin, and polylysine is 100:1-3:1-2:0.1-1.

4. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S1, the speed of heating to room temperature is 1-2°C / min; the homogenization speed is 8000-10000r / min.

5. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S2, the mass ratio of animal blood cell fluid, rare earth lanthanum chitosan chelate salt, glycine-sodium hydroxide buffer solution, and composite protease is 30-50:1-2:200-300:0.1-1; wherein, the concentration of glycine-sodium hydroxide buffer solution is 0.01-0.02 mol / L, and its pH value is 9-9.

6.

6. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S2, the specific activity of the composite protease was 5000-8000 U / g; The complex protease includes alkaline protease; The alkaline protease is at least one of baker's yeast alkaline protease, serine alkaline protease, Bacillus subtilis alkaline protease and streptomycin alkaline protease.

7. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S3, the pH value of the enzymatic hydrolyzate is adjusted to 5-6 using hydrochloric acid with a concentration of 1-2 mol / L.

8. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S3, the centrifugal speed is 5000-8000 r / min.

9. The method for preparing animal blood cell polypeptide powder according to claim 1, characterized in that: In S3, the low temperature spray drying temperature is 40-50°C.

10. An animal blood cell polypeptide powder, characterized in that: The animal blood polypeptide powder is prepared by the method for preparing the animal blood polypeptide powder according to claims 1-9.

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