Preparation method of earthworm protein peptide

Abstract

The invention discloses a preparation method of earthworm protein peptide, which comprises the following steps: by taking eisenia fetida as a raw material, firstly, crushing dried eisenia fetida, sieving with a 40-mesh sieve, and degreasing with methanol; then, the degreased eisenia fetida is crushed and sieved by a 80-mesh sieve; the preparation method comprises the following steps: adding crushed degreased raw materials into boiling water, inactivating for 30 minutes, washing with distilled water under the water bath condition of 45 DEG C for 3 times, centrifugally filtering each time, and taking solids for later use; mixing the washed raw materials with distilled water, and adding special protease for protein extraction for enzymolysis under the conditions that the water bath is 50 DEG C and the pH is 8.5-9.0. After the reaction is completed, cooling and centrifugally filtering to obtain enzymatic hydrolysate; and adjusting the pH value of the enzymatic hydrolysate to 7.0-8.0 by using dilute acetic acid, adding a hydrogen peroxide solution, carrying out decoloration treatment at 65-85 DEG C, cooling, carrying out centrifugal filtration, and carrying out spray drying to obtain an earthworm protein peptide product. The earthworm protein peptide product is white-like solid powder, the protein content is 85%-90%, the solubility is not lower than 5.0 g / 100g in neutral water at room temperature, and the earthworm protein peptide product is clear, transparent and free of peculiar smell.

Description

Technical Field

[0001] The invention belongs to the technical field of animal protein peptide preparation and relates to a method for preparing earthworm protein peptide. Background Art

[0002] Earthworms are one of the important Chinese medicinal materials. The earliest monograph on Chinese medicine, Shennong's Herbal Classic, contains 67 kinds of animal medicines, including earthworms. It is listed as a low-grade product in Shennong's Herbal Classic. It has the effects of clearing away heat and calming the nerves, unblocking meridians, relieving asthma, and diuresis. It has a high protein content and is an important source of high-quality protein, with good utilization value. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing earthworm protein peptide with high enzymolysis rate, low processing cost and good water solubility.

[0004] Based on the above purpose, the present application solves this need in the field by providing a method for preparing earthworm protein peptide.

[0005] On the one hand, the present invention relates to a method for preparing earthworm protein peptide, which comprises: using Eisenia fetida as a raw material, first crushing the dried Eisenia fetida, passing through a 40-mesh sieve, and defatting with methanol. Then crushing the defatted Eisenia fetida and passing through an 80-mesh sieve. Add the crushed defatted raw material to boiling water for inactivation for 30 minutes, then wash it with distilled water 3 times under a 45°C water bath condition, centrifuge and filter each time, and take the solid for standby use. Mix the washed raw material with distilled water, add a protein extraction special protease for enzymolysis under a water bath of 50°C and a pH of 8.5-9.0. After the reaction is completed, cool down, centrifuge and filter to obtain an enzymolysis solution. Adjust the pH of the enzymolysis solution to 7.0-8.0 with dilute acetic acid, add a hydrogen peroxide solution, decolorize at 65-85°C, centrifuge and filter after cooling, and spray dry to obtain an earthworm protein peptide product. The earthworm protein peptide product is an off-white solid powder with a protein content of 85%-90%. In neutral water at room temperature, the solubility is greater than 5.0g / 100g, and the product is clear and transparent with no peculiar smell.

[0006] Description 1: In the method for preparing earthworm protein peptide provided by the present invention, the mixing ratio of the earthworm Eisenia fetida and methanol during defatting is g:mL=1:3--5;

[0007] Note 2: In the method for preparing earthworm protein peptide provided by the present invention, the defatted Eisenia fetida raw material is inactivated in boiling water for 30 minutes to inactivate its autolytic enzymes such as autolytic enzymes;

[0008] Note 3, in the preparation method of earthworm protein peptide provided by the present invention, the inactivated raw material is mixed with distilled water at a ratio of solid / liquid = 1 / 5, and washed with water 3 times to remove water-soluble substances such as pigments, sugars, and salts;

[0009] Description 4, the present invention provides a method for preparing earthworm protein peptide, wherein the mixing ratio of the washed raw material and distilled water is solid / liquid (g / ml) = 1:8-10, the added amount ratio of raw material and protease is raw material / protease (g / g) = 100 / 1-3, the enzymatic hydrolysis conditions are water bath 50°C, PH8.5-9.0, and enzymatic hydrolysis time 4-5h;

[0010] Note 5, a method for preparing a ground dragon protein peptide provided by the present invention, after the protease hydrolysis reaction is completed, the temperature is lowered and centrifuged to obtain an enzymatic solution, the enzymatic solution is adjusted to pH 7.0-8.0 with dilute acetic acid, and hydrogen peroxide is added for decolorization, the amount of hydrogen peroxide added is the volume of the enzymatic solution / the volume of hydrogen peroxide (ml / ml)=100 / 1.5-2.5, and the decolorization temperature is 65-85°C;

[0011] Description 6, a method for preparing earthworm protein peptide provided by the present invention, wherein the decolorized reaction solution is cooled, centrifuged and filtered to obtain a clear solution, and then spray-dried to obtain an earthworm protein peptide product;

[0012] Note 7, the present invention provides a method for preparing earthworm protein peptide, the earthworm protein peptide product is a white solid powder, the protein content is between 85% and 90%, the solubility in room temperature neutral water is greater than 5.0g / 100g, and it is clear and transparent with no odor.

[0013] The present invention has the following beneficial effects or advantages:

[0014] (1) The present invention provides a method for preparing earthworm protein peptides, which realizes the process of enzymatically hydrolyzing the protein contained in earthworms into water-soluble protein peptides, thereby expanding the scope of use and application environment of earthworm proteins;

[0015] (2) The present invention provides a method for preparing earthworm protein peptides, which uses a protein extraction-specific protease to perform enzymatic hydrolysis, is safe and reliable, has good repeatability, and can obtain earthworm protein peptide products in a good manner;

[0016] (3) The present invention provides a method for preparing earthworm protein peptide, and the earthworm protein peptide product obtained by the method has good water solubility;

[0017] (4) The present invention provides a method for preparing earthworm protein peptides, which can effectively enrich the protein contained in earthworms during the protein peptide preparation process, thereby greatly improving the protein content; DETAILED DESCRIPTION

[0018] The technical solution of the present invention is described below in conjunction with embodiments; however, the present invention is not limited to the following embodiments.

[0019] Example 1

[0020] This example is an example of preparing earthworm protein peptides by adding earthworm (Eisenia fetida) raw material and protease in a ratio of 100:1 (g / g) for enzymatic hydrolysis and adding hydrogen peroxide in an amount of 100 / 1.5 for decolorization.

[0021] 100g of dried earthworm (Eisenia fetida) raw material was crushed and passed through a 40-mesh sieve, added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was dried and crushed, and passed through an 80-mesh sieve.

[0022] The crushed defatted raw material was added to 800-1000ml of distilled water kept at a slightly boiling state, stirred and kept warm for 30min, cooled to 45℃, stirred for 1h, centrifuged, the solid was added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid was added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid was added to 800ml distilled water, 50℃ water bath, 3.5% sodium hydroxide solution was used to adjust the pH between 8.5-9.0, 1.0g of protein extraction protease moistened with distilled water was added, the temperature and pH were maintained, and the enzymolysis was performed for 5h. After the reaction was completed, it was cooled to room temperature, centrifuged, and the enzymolysis solution was obtained. The solid was added to 400ml distilled water, stirred for 1h at 50℃ water bath, and centrifuged after cooling to obtain the extract.

[0023] Combine the enzymatic hydrolyzate and the extract to obtain a reaction solution, adjust the pH to 7.0-8.0 with 3.5% dilute acetic acid, add 1.5% hydrogen peroxide (concentration 30%) solution by volume of the reaction solution, and heat to 65°C and keep warm for 30 minutes, heat to 75°C and keep warm for 30 minutes, heat to 85°C and keep warm for 1.5-2.0 hours under open stirring, and add distilled water to the original volume of the reaction solution during this period. After decolorization is completed, cool to room temperature, centrifuge and filter to obtain a clear solution. Spray dry the clear solution to obtain the earthworm protein peptide product.

[0024] Example 2

[0025] This example is an example of preparing earthworm protein peptides by adding earthworm (Eisenia fetida) raw material and protease in a ratio of 100:2 (g / g) for enzymatic hydrolysis and adding hydrogen peroxide in an amount of 100 / 1.5 for decolorization.

[0026] 100g of dried earthworm (Eisenia fetida) raw material was crushed and passed through a 40-mesh sieve, added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was dried and crushed, and passed through an 80-mesh sieve.

[0027] The crushed defatted raw material is added to 800-1000ml of distilled water kept in a slightly boiling state, stirred and kept warm for 30min, cooled to 45℃, stirred for 1h, centrifuged, the solid obtained is added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid obtained is added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid obtained is added to 800ml distilled water, 50℃ water bath, 3.5% sodium hydroxide solution is used to adjust the pH between 8.5-9.0, 2.0g of protein extraction special protease moistened with distilled water is added, the temperature and pH are maintained, and the enzymolysis is performed for 4h. After the reaction is completed, it is cooled to room temperature, centrifuged, and the enzymolysis solution is obtained. The solid is added to 400ml distilled water, stirred for 1h in a 50℃ water bath, and centrifuged after cooling to obtain the extract.

[0028] Combine the enzymatic hydrolyzate and the extract to obtain a reaction solution, adjust the pH to 7.0-8.0 with 3.5% dilute acetic acid, add 1.5% hydrogen peroxide (concentration 30%) solution by volume of the reaction solution, and heat to 65°C and keep warm for 30 minutes, heat to 75°C and keep warm for 30 minutes, heat to 85°C and keep warm for 1.5-2.0 hours under open stirring, and add distilled water to the original volume of the reaction solution during this period. After decolorization is completed, cool to room temperature, centrifuge and filter to obtain a clear solution. Spray dry the clear solution to obtain the earthworm protein peptide product.

[0029] Example 3

[0030] This example is an example of preparing earthworm protein peptides by adding earthworm (Eisenia fetida) raw material and protease in a ratio of 100:3 (g / g) for enzymatic hydrolysis and adding hydrogen peroxide in an amount of 100 / 2.5 for decolorization.

[0031] 100g of dried earthworm (Eisenia fetida) raw material was crushed and passed through a 40-mesh sieve, added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was added to 400ml of methanol, degreased at 55-60℃ for 1h, and filtered. The obtained solid was dried and crushed, and passed through an 80-mesh sieve.

[0032] The crushed defatted raw material was added to 800-1000ml of distilled water kept at a slightly boiling state, stirred and kept warm for 30min, cooled to 45℃, stirred for 1h, centrifuged, the solid was added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid was added to 800-1000ml distilled water, stirred for 1h at 45℃, centrifuged, the solid was added to 800ml distilled water, 50℃ water bath, 3.5% sodium hydroxide solution was used to adjust the pH between 8.5-9.0, 3.0g of protein extraction special protease moistened with distilled water was added, the temperature and pH were maintained, and the enzymolysis was performed for 4h. After the reaction was completed, it was cooled to room temperature, centrifuged, and the enzymolysis solution was obtained. The solid was added to 400ml distilled water, stirred for 1h at 50℃ water bath, centrifuged after cooling, and the extract was obtained.

[0033] Combine the enzymatic hydrolyzate and the extract to obtain a reaction solution, adjust the pH to 7.0-8.0 with 3.5% dilute acetic acid, add 2.5% hydrogen peroxide (concentration 30%) solution by volume of the reaction solution, and heat to 65°C and keep warm for 30 minutes, heat to 75°C and keep warm for 30 minutes, heat to 85°C and keep warm for 1.5-2.0 hours under open stirring, and add distilled water to the original volume of the reaction solution during this period. After decolorization is completed, cool to room temperature, centrifuge and filter to obtain a clear solution. Spray dry the clear solution to obtain the earthworm protein peptide product.

[0034] The Kjeldahl method was selected to accurately determine the content of earthworm protein peptides in the earthworm (Eisenia fetida) raw material and the earthworm protein peptides obtained in Examples 1 to 3, as shown in Table 1.

[0035] Table 1. Protein content of earthworm (Eisenia fetida) raw material and earthworm protein peptide

[0036]

[0037] As shown in Table 1, Examples 1 to 3 can all obtain earthworm protein peptide products well. The protein content of the raw materials and products was detected. The protein content of the raw materials was 61.37%. The protein content of the products obtained from Examples 1 to 3 was significantly improved compared with the raw materials.

[0038] The solubility test results of the earthworm protein peptides obtained in Examples 1 to 3 in neutral water at room temperature are shown in Table 2.

[0039] Table 2. Solubility test results of earthworm protein peptide in neutral water at room temperature

[0040] Earthworm protein peptide / g Pure water / g Solubility Solution state Example 1 5.0 100.0 Shake gently to dissolve completely Clear, no odor Example 2 5.0 100.0 Shake gently to dissolve completely Clear, no odor Example 3 5.0 100.0 Shake gently to dissolve completely Clear, no odor

[0041] As shown in Table 2, the earthworm (Eisenia fetida) protein peptides obtained in Examples 1 to 3 can be quickly and completely dissolved in neutral water at room temperature at a solubility concentration of 5.0%, and the solution is clear and has no odor.

[0042] As described above, the present invention can be well implemented. The above embodiments are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various changes and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the present invention.

Claims

1. A method for preparing earthworm protein peptide, characterized in that: Using Eisenia fetida as raw material, firstly crush the dried Eisenia fetida, pass through a 40-mesh sieve, and degrease with methanol. Then crush the defatted Eisenia fetida and pass through an 80-mesh sieve. Add the crushed defatted raw material into boiling water for inactivation for 30 minutes, then wash it with distilled water 3 times under 45°C water bath conditions, centrifuge and filter each time, and take the solid for standby use. Mix the washed raw material with distilled water, add a protein extraction special protease for enzymolysis under 50°C water bath and pH 8.5-9.0 conditions. After the reaction is completed, cool down, centrifuge and filter to obtain an enzymolysis solution. Adjust the pH of the enzymolysis solution to 7.0-8.0 with dilute acetic acid, add hydrogen peroxide solution, decolorize at 65-85°C, centrifuge and filter after cooling, and spray dry to obtain the earthworm protein peptide product. The earthworm protein peptide product is an off-white solid powder with a protein content of 85%-90%. In neutral water at room temperature, the solubility is greater than 5.0g / 100g, and the product is clear and transparent with no peculiar smell.

2. The method according to claim 1, characterized in that The mixing ratio of the Eisenia fetida and methanol during defatting is g:mL=1:3--5; 3. The method according to claim 1, characterized in that The defatted Eisenia fetida raw material is inactivated in boiling water for 30 minutes to inactivate its autolytic enzymes such as autolytic enzymes; 4. The method according to claim 1, characterized in that: The inactivated raw material is mixed with distilled water at a ratio of solid / liquid = 1 / 5, and washed with water 3 times to remove water-soluble substances such as pigments, sugars, and salts; 5. The method according to claim 1, characterized in that The mixing ratio of the washed raw material and distilled water is solid / liquid (g / ml) = 1:8-10, the addition ratio of the raw material and protease is raw material / protease (g / g) = 100 / 1-3, the enzymatic hydrolysis conditions are water bath 50°C, pH 8.5-9.0, and enzymatic hydrolysis time 4-5h; 6. The method according to claim 1, characterized in that After the protease hydrolysis reaction is completed, the temperature is lowered and centrifuged to obtain an enzymatic solution, the enzymatic solution is adjusted to a pH of 7.0-8.0 with dilute acetic acid, and hydrogen peroxide is added for decolorization, the amount of hydrogen peroxide added is the volume of the enzymatic solution / the volume of hydrogen peroxide (ml / ml)=100 / 1.5-2.5, and the decolorization temperature is 65-85°C; 7. The method according to claim 1, characterized in that The decolorized reaction solution is cooled, centrifuged and filtered to obtain a clear solution, and spray-dried to obtain a ground dragon protein peptide product; 8. The method according to claim 1, characterized in that: The earthworm protein peptide product is an off-white solid powder with a protein content of 85%-90%. In neutral water at room temperature, the solubility is greater than 5.0g / 100g, and the product is clear and transparent with no peculiar smell.

9. The method according to claim 1, characterized in that: The concentration of the dilute acetic acid solution is 3.5%; the concentration of the dilute sodium hydroxide solution is 3.5%; 10. The method according to claim 1, characterized in that The centrifugal condition is 5000 r / min and the time is 20 min.

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