Rumen bypass cottonseed protein as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of animal feed, and discloses rumen bypass cottonseed protein as well as a preparation method and application thereof. The rumen bypass cottonseed protein is prepared by the following steps: pretreating bare cottonseeds, softening, tempering, flaking and drying to obtain cooked cottonseed embryo slices, degreasing and dephenolizing the cooked cottonseed embryo slices to obtain degreased and dephenolized embryo slices, removing a solvent from the degreased and dephenolized embryo slices, grinding, and screening to obtain the rumen bypass cottonseed protein. The preparation method provided by the invention is simple in process and convenient to operate, and the rumen bypass cottonseed protein with the crude protein content being 60% or above and the protein rumen bypass rate being 80% or above can be obtained. The invention provides the rumen bypass protein preparation method which is not easy to generate solvent residues and has small change in feed sensory quality.

Description

Technical Field

[0001] The invention belongs to the technical field of animal feed, and relates to rumen bypass cottonseed protein and a preparation method and application thereof. Background Art

[0002] Rumen Bypass Protein refers to the protein in the feed of ruminants that can pass through the rumen without being degraded by the microorganisms in the rumen and can directly enter the small intestine for digestion and absorption. It is also called rumen undegraded protein (UDP). After entering the abomasum (abomasum) and small intestine of dairy cows, this part of protein is degraded into short peptides, amino acids and other small molecules by the digestive enzymes therein and absorbed by the small intestine. Properly increasing the content of rumen bypass protein in feed can reduce the reduction in nutrient utilization efficiency caused by the "secondary conversion" of protein, improve the effective utilization rate of protein, and meet the protein requirements of high-yielding animals. Rumen bypass protein plays an important role in maintaining and improving the production performance of ruminants, especially for high-yielding dairy cows and fast-growing calves, which have a large demand for amino acids, and rumen bypass protein can provide this part of the additional amino acid requirements.

[0003] The existing methods for improving the rumen passage rate of feed protein mainly include heat treatment, chemical treatment and physical coating. Heat treatment includes dry heat, roasting, high pressure heating, steam heating and other methods. It mainly utilizes the characteristic that protein is easy to deform at high temperature. At high temperature, the hydrophobic groups of protein molecules are exposed to more on the molecular surface, thereby reducing the solubility of protein and thus reducing the degradation rate of protein in the rumen; chemical treatment is the use of chemical treatment agents such as formaldehyde, zinc salts, tannins, etc. These chemical treatment agents react with protein to form compounds that are not easily degraded by rumen microorganisms, thereby reducing the degradation rate of protein in the rumen; materials commonly used in physical coating include albumin, polymers and compounds that are not easily degraded by rumen microorganisms. Spraying the above materials on the surface of protein feed can protect the protein and reduce the rumen degradation rate.

[0004] Commonly used chemical treatment agents are prone to drug residues, which can affect animal health. They can also affect the sensory properties of feed, reducing animal appetite and feed intake. Although physical coating has the advantage of increasing the content of rumen bypass protein, the coating process requires precise control and has high technical requirements. The thickness and uniformity of the coating will have a great impact on the rumen bypass rate. Therefore, it is of great significance to explore a method for preparing rumen bypass protein that is less likely to have drug residues, has less impact on the sensory quality of feed, and has a simple process. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a rumen-passed cottonseed protein and a preparation method and application thereof. After pre-treatment of light cottonseed, softening and tempering, embryo rolling and drying are performed to obtain cooked cottonseed embryo flakes, the cooked cottonseed embryo flakes are defatted and dephenolized to obtain defatted and dephenolized embryo flakes, the defatted and dephenolized embryo flakes are desolventized, ground and sieved to obtain the rumen-passed cottonseed protein. The preparation method provided by the present invention has a simple process and is easy to operate, and can obtain rumen-passed cottonseed protein with a crude protein content of more than 60% and a protein rumen-passing rate of more than 80%. In addition, the preparation method of the present invention is not easy to produce solvent residues and has little effect on the sensory quality of the feed.

[0006] To achieve the technical purpose of the present invention, on the one hand, the present invention provides a method for preparing rumen bypass cottonseed protein, which specifically comprises the following steps:

[0007] S1: Cotton seed pretreatment: The cotton seeds are conditioned by water, impurities are removed, and the seeds are crushed by a shelling machine and the shells and kernels are separated to obtain cotton kernels with a shell content of less than 5% and a powder content of less than 15%; the moisture content of the cotton seeds after water conditioning is 9-10wt%;

[0008] S2: Embryo rolling: the cotton kernels are softened and tempered at 75-80°C for 20-25 minutes to obtain cotton kernels with a moisture content of 10-11 wt%, and then embroided to obtain embryo sheets with a thickness of 0.3-0.4 mm, which are then dried at 110-120°C for 26-30 minutes to obtain cooked cotton kernel embryo sheets;

[0009] S3: degreasing: adding n-hexane to the cooked cotton kernel embryo flakes for degreasing, the ratio of the mass of the embryo flakes to the volume of n-hexane added is 1:1.2-1.4, the degreasing temperature is 55-60°C, the degreasing time is 100-120min, and the defatted embryo flakes are obtained;

[0010] S4: dephenolization: adding 90 vol% methanol solution to the defatted embryo slices for dephenolization, the ratio of the mass of the defatted embryo slices to the volume of the methanol solution added is 1:0.8-1.1, the dephenolization temperature is 40-45°C, the dephenolization time is 70-90 min, and the defatted and dephenolized embryo slices are obtained;

[0011] S5: Desolventization: The defatted and dephenolized embryo flakes are extruded, and the wet meal after extrusion contains 30-35wt% solvent, then xylose solution and water are added, and the meal is put into a pre-degassing pot and stirred for 10 minutes. After stirring, the solvent and water are removed by evaporation in a disc dryer and a tempering pot. The drying and tempering process is controlled at a temperature of 105°C and a time of 130 minutes, wherein the drying time is 90-100 minutes and the tempering time is 30-40 minutes; the amount of xylose solution added is 2% of the mass of the wet meal, the concentration of the xylose solution is 50wt%, and the amount of water added is 10% of the mass of the wet meal;

[0012] S6: Grinding: After the material after desolventizing in S5 is cooled, it is ground and passed through a 40-mesh sieve to obtain rumen-passed cottonseed protein.

[0013] Optionally, the shelling machine crushing and the shell-kernel separation are carried out by shelling with a knife shelling machine, a step screen, a flat rotary screen, and a kernel-shell separator to remove the shells, thereby obtaining cotton kernels with a shell content of less than 5%.

[0014] On the other hand, the present invention claims protection for a rumen bypass cottonseed protein prepared using the above-mentioned method for preparing rumen bypass cottonseed protein.

[0015] On the other hand, the present invention claims protection for the use of the above-mentioned rumen bypass cottonseed protein in ruminant feed.

[0016] In addition, the present invention seeks to protect the use of the above-mentioned method for preparing rumen bypass cottonseed protein in improving the rumen bypass protein rate and / or in vitro digestibility of protein feed.

[0017] The present invention determines the protein content, rumen passing rate and in vitro digestibility of the rumen-passed cottonseed protein and finds that the protein content of the rumen-passed cottonseed protein obtained by the preparation method of the present invention is more than 60%, the rumen passing rate is 80.7-81.4%, the rumen passing rate is more than 80%, and the in vitro digestibility is more than 54%. The rumen passing rate of the rumen-passed cottonseed protein prepared beyond the process parameter range of the present invention is significantly reduced, and the in vitro digestibility is significantly reduced. The preparation method of the present invention can significantly improve the rumen passing rate of the rumen-passed cottonseed protein, and the present invention provides a high-quality rumen-passed protein for ruminants.

[0018] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects or advantages:

[0019] The preparation method provided by the present invention can significantly improve the rumen passing rate of rumen passing cottonseed protein, the protein content of the rumen passing cottonseed protein is more than 60%, and the rumen passing rate is more than 80%. The present invention determines the protein content, rumen passing rate and in vitro digestibility of the rumen passing cottonseed protein and finds that the protein content of the rumen passing cottonseed protein obtained by the preparation method of the present invention is more than 60%, the rumen passing rate is 80.7-81.4%, the rumen passing rate is more than 80%, and the in vitro digestibility is more than 54%. The rumen passing rate of the rumen passing cottonseed protein prepared beyond the process parameter range of the present invention is significantly reduced, and the in vitro digestibility is significantly reduced. The present invention provides a high-quality rumen passing protein for ruminants.

[0020] In the process of preparing rumen-free protein of the present invention, n-hexane and methanol, which are easy to volatilize and separate and not easy to produce solvent residues, are used to extract fat and cottonpol in cottonseed, thereby reducing the risk of solvent residues to animal health, and n-hexane and methanol will not produce chemical reactions with nutrients in cottonseed, and have little effect on the sensory properties of feed. The preparation method provided by the present invention can reduce the amount of solvent used in the defatting and dephenolization processes, and is more energy-saving and economical. The preparation method provided by the present invention can simultaneously achieve solvent removal and steam conditioning, simplify the process flow, reduce energy consumption, and improve production efficiency.

[0021] The present invention provides a method for preparing rumen bypass protein with simple process and convenient operation. The preparation method provided by the present invention can be completed by simple process equipment, without adding new equipment, and has low requirements on operation. In addition, the method of the present invention adopts a lower preparation temperature, which can achieve the purpose of energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a process flow chart for preparing high-protein rumen bypass cottonseed protein. DETAILED DESCRIPTION

[0023] The technical scheme of the present invention is now described in conjunction with the embodiments, but the present invention is not limited to the following embodiments. The experimental methods and detection methods described in the following embodiments are conventional methods unless otherwise specified; the reagents and materials described are all commercially available unless otherwise specified.

[0024] Example 1

[0025] This embodiment provides a method for producing high-protein rumen bypass cottonseed protein, which specifically comprises the following steps:

[0026] S1: Cotton seed pretreatment: The cotton seeds are conditioned by water, impurities are removed, and the seeds are crushed by a shelling machine and the shells and kernels are separated to obtain cotton kernels with a shell content of less than 5% and a powder content of less than 15%; the moisture content of the cotton seeds after water conditioning is 9-10wt%;

[0027] S2: Embryo rolling: the cotton kernels are softened and tempered (steam softened) at 80°C for 20 minutes to obtain cotton kernels with a moisture content of 10-11 wt%, and then embroided to obtain embryo sheets with a thickness of 0.3-0.4 mm, which are then dried at 120°C for 26 minutes to obtain cooked cotton kernel embryo sheets;

[0028] S3: Degreasing: adding n-hexane to the cooked cotton kernel embryo flakes for degreasing, the ratio of the embryo flake mass to the added volume of n-hexane is 1:1.2, the degreasing temperature is 55°C, the degreasing is performed for 120 minutes, and the defatted embryo flakes are obtained;

[0029] S4: dephenolization: adding 90 vol% methanol solution to the defatted embryo slices for dephenolization, the ratio of the mass of the defatted embryo slices to the volume of the methanol solution added is 1:0.8, the dephenolization temperature is 40°C, the dephenolization time is 90 minutes, and the defatted and dephenolized embryo slices are obtained;

[0030] S5: Desolventization: The defatted and dephenolized embryo flakes are extruded, and the wet meal after extrusion contains 45-50wt% solvent, then xylose solution and water are added, and the mixture is input into a pre-degassing pot (unheated disc dryer) and stirred for 10 minutes. After stirring, the mixture is passed through a disc dryer and a tempering pot for evaporation to remove the solvent and water. The drying and tempering process is controlled at a temperature of 105°C and a time of 130 minutes (drying for 90 minutes and tempering for 40 minutes); the amount of xylose solution added is 2% of the mass of the wet meal, the concentration of the xylose solution is 50wt%, and the amount of water added is 10% of the mass of the wet meal;

[0031] S6: Grinding: After the material after desolventizing in S5 is cooled, it is ground and sieved (through a 40-mesh sieve) to obtain rumen-passed cottonseed protein.

[0032] Optionally, the shelling machine crushing and the shell-kernel separation are carried out by shelling with a knife shelling machine, a step screen, a flat rotary screen, and a kernel-shell separator to remove the shells, thereby obtaining cotton kernels with a shell content of less than 5%.

[0033] Specifically, softening and conditioning before flaking in S2 can increase the plasticity of cotton kernels, facilitate flaking, and reduce the oil yield and powder content of flaking; and adding water and xylose solution in S5 promotes the Maillard reaction.

[0034] Example 2

[0035] This embodiment provides a method for producing high-protein rumen bypass cottonseed protein, which specifically comprises the following steps:

[0036] S1: Cotton seed pretreatment: The cotton seeds are conditioned by water, impurities are removed, and the seeds are crushed by a shelling machine and the shells and kernels are separated to obtain cotton kernels with a shell content of less than 5% and a powder content of less than 15%; the moisture content of the cotton seeds after water conditioning is 9-10wt%;

[0037] S2: Embryo rolling: The cotton kernels are softened and tempered (steam softened) at 78°C for 22 minutes to obtain cotton kernels with a moisture content of 10-11 wt%, and then embroided to obtain embryo sheets with a thickness of 0.3-0.4 mm, which are then dried at 115°C for 28 minutes to obtain cooked cotton kernel embryo sheets;

[0038] S3: Degreasing: adding n-hexane to the cooked cotton kernel embryo flakes for degreasing, the ratio of the embryo flake mass to the added volume of n-hexane is 1:1.3, the degreasing temperature is 58°C, the degreasing time is 110min, and the defatted embryo flakes are obtained;

[0039] S4: dephenolization: adding 90 vol% methanol solution to the defatted embryo slices for dephenolization, the ratio of the mass of the defatted embryo slices to the volume of the methanol solution added is 1:1, the dephenolization temperature is 42°C, the dephenolization time is 80 min, and the defatted and dephenolized embryo slices are obtained;

[0040] S5: Desolventization: The defatted and dephenolized embryo flakes are extruded, and the wet meal after extrusion contains 45-50wt% solvent, then xylose solution and water are added, and the meal is input into a pre-degassing pot (unheated disc dryer) and stirred for 10 minutes. After stirring, the solvent and water are removed by evaporation in a disc dryer and a tempering pot. The drying and tempering process is controlled at a temperature of 105°C and a time of 130 minutes (drying for 95 minutes and tempering for 35 minutes); the amount of xylose solution added is 2% of the mass of the wet meal, the concentration of xylose solution is 50wt%, and the amount of water added is 10% of the mass of the wet meal;

[0041] S6: Grinding: After the material after desolventizing in S5 is cooled, it is ground and sieved (through a 40-mesh sieve) to obtain rumen-passed cottonseed protein.

[0042] Specifically, softening and conditioning before flaking in S2 can increase the plasticity of cotton kernels, facilitate flaking, and reduce the oil yield and powder content of flaking; and adding water and xylose solution in S5 promotes the Maillard reaction.

[0043] Example 3

[0044] This embodiment provides a method for producing high-protein rumen bypass cottonseed protein, which specifically comprises the following steps:

[0045] S1: Cotton seed pretreatment: The cotton seeds are conditioned by water, impurities are removed, and the seeds are crushed by a shelling machine and the shells and kernels are separated to obtain cotton kernels with a shell content of less than 5% and a powder content of less than 15%; the moisture content of the cotton seeds after water conditioning is 9-10wt%;

[0046] S2: Embryo rolling: the cotton kernels are softened and tempered at 75°C for 25 minutes to obtain cotton kernels with a moisture content of 10-11 wt%, and then embroided to obtain embryo sheets with a thickness of 0.3-0.4 mm, which are then dried at 110°C for 30 minutes to obtain cooked cotton kernel embryo sheets;

[0047] S3: Degreasing: adding n-hexane to the cooked cotton kernel embryo flakes for degreasing, the ratio of the mass of the embryo flakes to the volume of n-hexane added is 1:1.4, the degreasing temperature is 60°C, the degreasing is performed for 100 minutes, and the defatted embryo flakes are obtained;

[0048] S4: dephenolization: adding 90 vol% methanol solution to the defatted embryo slices for dephenolization, the ratio of the mass of the defatted embryo slices to the volume of the methanol solution added is 1:1.1, the dephenolization temperature is 45°C, the dephenolization time is 70 minutes, and the defatted and dephenolized embryo slices are obtained;

[0049] S5: Desolventization: The defatted and dephenolized embryo flakes are extruded, and the wet meal after extrusion contains 45-50wt% solvent, then xylose solution and water are added, and the mixture is input into a pre-desolventizing pot (unheated disc dryer) and stirred for 10 minutes. After stirring, the mixture is passed through a disc dryer and a tempering pot to remove the solvent and water, and the drying and tempering process is controlled at a temperature of 105°C and a time of 130 minutes (drying for 100 minutes and tempering for 30 minutes); the amount of xylose solution added is 2% of the mass of the wet meal, the concentration of the xylose solution is 50wt%, and the amount of water added is 10% of the mass of the wet meal;

[0050] S6: Grinding: After the material after desolventizing in S5 is cooled, it is ground and sieved to obtain rumen-pass cottonseed protein.

[0051] Specifically, softening and conditioning before flaking in S2 can increase the plasticity of cotton kernels, facilitate flaking, and reduce the oil yield and powder content of flaking; and adding water and xylose solution in S5 promotes the Maillard reaction.

[0052] Comparative Example 1

[0053] The preparation method of rumen-bypass cottonseed protein in this comparative example is the same as that in Example 1, except that the ratio of the mass of defatted embryo flakes to the volume of methanol solution added is 1:2.5.

[0054] Comparative Example 2

[0055] The preparation method of rumen bypass cottonseed protein in this comparative example is the same as that in Example 1, except that no xylose solution is added in S5.

[0056] Comparative Example 3

[0057] The preparation method of rumen bypass cottonseed protein in this comparative example is the same as that in Example 1, except that the time for the drying and conditioning process in S5 is 30 minutes.

[0058] Example 4

[0059] This example provides the determination of protein content, rumen bypass rate, and small intestinal digestibility of rumen bypass cottonseed protein.

[0060] The protein content of rumen-passed cottonseed protein was determined by the Kjeldahl method, and the rumen-passing rate and small intestine digestibility of rumen-passed cottonseed protein were determined by the rumen nylon bag method and the three-step in vitro method. The results are shown in Table 1.

[0061] Table 1: Rumen-bypass effect of cottonseed protein

[0062]

[0063]

[0064] As can be seen from Table 1, the protein content of the rumen-passing cottonseed protein obtained by the preparation method of the present invention is more than 60%, the rumen-passing rate is 80.7-81.4%, the rumen-passing rate is >80%, and the small intestine digestibility is more than 54%. The rumen-passing rate of the rumen-passing cottonseed protein prepared beyond the process parameter range of the present invention is significantly reduced, and the small intestine digestibility is significantly reduced. It can be seen that the preparation method of the rumen-passing cottonseed protein provided by the present invention can significantly improve the rumen-passing rate of the rumen-passing protein, and provide a high-quality rumen-passing protein preparation method for improving the production performance of ruminants.

[0065] As described above, the basic principle, main features and advantages of the present invention are well described. The above embodiments and descriptions are only descriptions of the preferred embodiments of the present invention, and the present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, various changes and improvements made by ordinary technicians in this field to the technical solution of the present invention should fall within the protection scope determined by the present invention.

Claims

1. A method for preparing rumen bypass cottonseed protein, characterized in that: include: The light cotton seeds are pretreated, softened and tempered, rolled and dried to obtain cooked cotton kernel embryo flakes, the cooked cotton kernel embryo flakes are defatted and dephenolized to obtain defatted and dephenolized embryo flakes, the defatted and dephenolized embryo flakes are desolventized, ground and sieved to obtain the rumen-passed cottonseed protein; The dephenolization uses a 90 vol% methanol solution, the ratio of the mass of the defatted embryo slices obtained by the degreasing to the volume of the methanol solution added is 1:0.8-1.1, and the dephenolization temperature is 40-45°C.

2. The method for preparing rumen bypass cottonseed protein according to claim 1, characterized in that: The solvent removal includes extrusion removal, pre-removal, drying and conditioning removal, and the wet meal contains 30-35wt% of solvent after extrusion removal; The pre-removal includes adding xylose solution and water, inputting into the pre-removal pot and stirring for 10 minutes; The drying and conditioning removal temperature is 105°C and the time is 130 minutes; The drying is performed using a dryer, and the conditioning is performed using a conditioning pot.

3. The method for preparing rumen bypass cottonseed protein according to claim 2, characterized in that: The concentration of the xylose solution is 50wt%, the amount of the xylose solution added is 2% of the mass of the wet meal, and the amount of water added is 10% of the mass of the wet meal.

4. The method for preparing rumen bypass cottonseed protein according to claim 1, characterized in that: The degreasing uses normal hexane, the ratio of the mass of the cooked cotton kernel embryo piece to the volume of the added normal hexane is 1:1.2-1.4, and the degreasing temperature is 55-60°C.

5. The method for preparing rumen bypass cottonseed protein according to claim 1, characterized in that: The softening and tempering temperature is 75-80° C., the time is 20-25 min, and the moisture content of the cotton kernel after softening and tempering is 10-11 wt %.

6. The method for preparing rumen bypass cottonseed protein according to claim 1, characterized in that: The flaking process obtains a flaked sheet with a thickness of 0.3 to 0.4 mm; The drying temperature is 110-120° C. and the drying time is 26-30 minutes.

7. The method for preparing rumen bypass cottonseed protein according to claim 1, characterized in that: The light cottonseed pretreatment includes water conditioning, impurity removal and shelling; The moisture content of the cottonseed after water conditioning is 9-10wt%; After the shelling, cotton kernels with a shell content of less than 5% are obtained.

8. A rumen bypass cottonseed protein, characterized in that: The invention is prepared by the method for preparing rumen bypass cottonseed protein according to any one of claims 1 to 7.

9. Use of the rumen bypass cottonseed protein according to claim 8 in ruminant feed.

10. Use of the method for preparing rumen bypass cottonseed protein according to any one of claims 1 to 7 in improving the rumen bypass protein rate and / or in vitro digestibility of protein feed.

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