High-digestibility corn protein concentrate and preparation method thereof

Abstract

The invention discloses high-digestibility corn protein concentrate and a preparation method thereof. The crude protein content of the high-digestibility corn protein concentrate is greater than or equal to 75%; the broiler bionic protein digestibility is greater than or equal to 85%. The crude protein content of the corn protein powder is increased in a mode of removing starch sugar in the corn protein through enzymolysis and filter pressing, the specific gravity of water to materials is reduced to (3-4): 1 when the starch sugar is removed, generation of wastewater is reduced, the production cost is reduced, the characteristic that the corn protein is acidic is utilized, acid protease is added for partial enzymolysis, and the yield of the corn protein is increased. The protein digestibility of the corn protein powder is improved at low cost, and the method has the advantage of high operability.

Description

Technical Field

[0001] The invention relates to the field of plant protein processing, and in particular to a high-digestibility corn protein concentrate and a preparation method thereof. Background Art

[0002] For farmed animals such as broilers and aquaculture, in order to achieve faster growth and higher feed conversion efficiency, it is usually necessary to design high-protein and high-energy feed formulas. For example, the crude protein level of broiler feed will reach 22-25%, and the metabolizable energy will reach 3300-3400 kcal / kg; the crude protein level of aquaculture feed will reach 28-55%, and the fat will reach 8-15%. Therefore, when designing broiler and aquaculture feed formulas, protein raw materials with high protein content and high digestibility are required.

[0003] Among the protein raw materials currently available, animal protein is expensive and has quality stability. The large-scale use of animal protein in feed not only increases the feed cost, but also affects the production performance and breeding benefits of animals. Although a large number of plant proteins such as rapeseed meal, cottonseed meal, soybean meal, peanut meal, DDGS, etc. are relatively cheap, their protein content and protein digestibility are often limited, which limits their use in the formula. Although a few plant proteins such as corn protein, cottonseed protein, and soybean protein concentrate have a protein content of 60-65%, their use is still limited by their insufficient protein content, low protein digestibility (generally only 50-75%), and high price of individual proteins. Therefore, the development of a plant protein raw material with higher protein content, higher protein digestibility, and lower price is of great significance to further optimize the effect and cost of aquatic and broiler feed formulas.

[0004] According to the test and analysis, the crude protein content of corn gluten meal is 58-62%, the bionic protein digestibility for broilers is about 70-75%, the in vitro protein digestibility for aquatic animals is 50-65%, and the carbohydrates are as high as about 28%. If the carbohydrates can be removed under certain conditions, the protein content of corn gluten meal can be further greatly increased, and the protein digestibility can be improved through appropriate process treatment, so that the characteristics of higher protein content and protein digestibility can be met, thereby meeting the needs of broiler and aquatic feed formulations.

[0005] The Chinese patent application with application number 202410221543.X discloses a high-protein, high-small-molecule active substance corn enzymatic protein and a preparation method, which provides a corn enzymatic protein with a crude protein content of >65% by removing starch. However, during the starch removal process, the ratio of water to material is 6-10:1, a large amount of wastewater is generated during the production process, and the production cost is high. The present application reduces the ratio of water to material to 3-4:1 after increasing the degree of enzymatic hydrolysis, thereby significantly reducing the generation of wastewater and saving costs. Summary of the invention

[0006] One of the purposes of the present invention is to provide a high digestibility corn protein concentrate to solve the problem of low crude protein content and low digestibility of corn protein powder in the prior art.

[0007] The present invention is achieved through the following technical scheme: a high-digestibility corn protein concentrate, wherein the crude protein content of the high-digestibility corn protein concentrate is ≥75%; and the digestibility of broiler bionic protein is ≥85%.

[0008] Another aspect of the present invention provides a method for preparing high digestibility corn protein concentrate, which is used to prepare the high digestibility corn protein concentrate as described above.

[0009] Furthermore, the preparation method may include the following steps:

[0010] The water and corn protein powder are mixed and added into an enzymolysis tank, and alkali is added to adjust the pH of the mixture of corn protein and water in the enzymolysis tank to 5.0, the weight ratio of the water to the corn protein powder is 3-4:1, and the alkali includes sodium hydroxide, sodium carbonate and calcium hydroxide; amylase and saccharifying enzyme are added into the enzymolysis tank and stirred to perform a first enzymolysis; the material obtained after the stirring is filtered through a plate and frame filter press to obtain a filter cake; the filter cake and water are mixed and poured into the enzymolysis tank, and acid protease is added into the enzymolysis tank and stirred to perform a second enzymolysis; the material obtained after the second enzymolysis is dried, and the dried material is crushed to obtain corn concentrated protein, the drying temperature of the drying is 100-120°C, the drying time is 16-20h, and the moisture content of the dried material is 5-8%.

[0011] Furthermore, the enzymatic hydrolysis temperature of the first enzymatic hydrolysis is 58° C., and the stirring time is 4 to 6 hours; the enzymatic hydrolysis temperature of the second enzymatic hydrolysis is 55° C., and the stirring time is 6 to 8 hours.

[0012] Further, the weight ratio of amylase to corn gluten powder is 3-5:1000, the weight ratio of saccharifying enzyme to corn gluten powder is 4-6:10000, and the weight ratio of acid protease to corn gluten powder is 3-5:1000;

[0013] Furthermore, the enzymatic activity of the amylase is 20000 U / g, the enzymatic activity of the saccharifying enzyme is 200000 U / g, and the enzymatic activity of the acidic protease is 200000 U / g.

[0014] Furthermore, the moisture content of the filter cake is 45-55%, and the weight ratio of the filter cake to water is 100:60-70.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] The invention increases the crude protein content of corn gluten powder by removing starch sugar in corn gluten through enzymatic hydrolysis and filtration, and when removing starch sugar, the ratio of water to material is reduced to 3-4:1, thereby reducing the generation of waste water and reducing the production cost. In addition, by utilizing the acidic characteristics of corn gluten, acidic protease is added to partially hydrolyze it, thereby increasing the protein digestibility of corn gluten powder at low cost, and the invention has the advantage of strong operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention.

[0018] Figure 1 A method flow chart of embodiment 1 of the present invention is shown. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0020] Unless otherwise specified, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail. Regarding the "comprising", "including", "having", "containing" and the like used herein, they are all open-ended terms, that is, they mean including but not limited to. Unless the context clearly indicates otherwise, the expressions "a" and "one" used herein include plural references. For example, the term "about" used herein means a range of ±20% of the value thereafter. In some embodiments, the term "about" means a range of ±10% of the value thereafter. In some embodiments, the term "about" means a range of ±5% of the value thereafter.

[0021] Embodiment 1:

[0022] Figure 1 The method flow chart of this exemplary embodiment is shown, and this exemplary embodiment provides a method for preparing high digestibility corn protein concentrate. Specifically, it includes the following steps:

[0023] Step 1: Mix water and corn gluten powder and add them to an enzymatic hydrolysis tank, and add alkali to adjust the pH of the mixture of corn gluten and water in the enzymatic hydrolysis tank to 5.0. The weight ratio of water to corn gluten powder is 3-4:1, and the alkali includes sodium hydroxide, sodium carbonate and calcium hydroxide.

[0024] Step 2: Add amylase and saccharifying enzyme into the enzymolysis tank and stir to perform the first enzymolysis. The enzymolysis temperature of the first enzymolysis is 58°C and the stirring time is 4-6 hours.

[0025] Specifically, the weight ratio of amylase to corn gluten meal is 3-5:1000, and the enzymatic activity of amylase is 20000U / g; the weight ratio of saccharifying enzyme to corn gluten meal is 4-6:10000, and the enzymatic activity of saccharifying enzyme is 200000U / g.

[0026] Step 3: The material obtained after stirring is filtered through a plate and frame filter press to obtain a filter cake. The moisture content of the obtained filter cake is 45-55%.

[0027] Step 4: Pour the filter cake and water into the enzymolysis tank, add acid protease into the enzymolysis tank and stir to perform the second enzymolysis. The weight ratio of the filter cake to water is 100:60-70. The enzymolysis temperature of the second enzymolysis is 55°C, and the stirring time is 6-8h.

[0028] Specifically, the weight ratio of acidic protease to corn protein powder is 3-5:1000, and the enzymatic activity of acidic protease is 200000 U / g.

[0029] Step 5: drying the material obtained after the second enzymatic hydrolysis, and crushing the dried material to obtain corn protein concentrate, the drying temperature is 100-120° C., the drying time is 16-20 h, and the moisture content of the dried material is 5-8%.

[0030] In order to better understand the high digestibility corn protein concentrate and preparation method thereof provided in this exemplary embodiment, the content of this method is further explained below in conjunction with the accompanying drawings and examples.

[0031] Embodiment 2:

[0032] In this embodiment, ordinary corn protein is converted into high-protein and high-digestibility corn protein concentrate by using an enzymatic hydrolysis tank and a plate and frame filter press, which specifically includes the following steps:

[0033] Step 1: Add 1200kg of water to the enzymolysis tank, and weigh 300kg of corn protein powder or corn protein slurry, add it to the enzymolysis tank, start stirring, and keep the temperature in the enzymolysis tank at 58°C. Add 0.6kg of sodium hydroxide to the enzymolysis tank and adjust the pH of the material in the tank to about 5.0. Weigh 1.2kg of amylase and 0.18kg of saccharifying enzyme and add them to the enzymolysis tank, keep the temperature at 58°C, and stir for 4 hours.

[0034] Step 2: Filter the material treated in step 1 in a 540L plate and frame filter press to obtain a filter cake. The moisture content of the filter cake is 49%.

[0035] Step 3: Add 510 kg of water to the enzymolysis tank, add the filter cake obtained in step 2 to the enzymolysis tank, start stirring, and keep the temperature in the enzymolysis tank at 55. Weigh 1.2 kg of acid protease, add it to the enzymolysis tank, keep the temperature at 55°C, and stir for 6 hours. The weight ratio of filter cake to water is 100:65.

[0036] Step 4: The material obtained after the secondary enzymatic hydrolysis is dried at 120° C. for 17 hours, and the moisture content of the dried material is 5%. The dried material is crushed to obtain corn protein concentrate A obtained by enzymatic hydrolysis.

[0037] Experimental Example 1:

[0038] In this experimental example, various indicators of corn protein powder raw material and corn protein concentrate prepared by the method in Example 1 were tested according to the GB / T method. The results are shown in Table 1.

[0039] Table 1 Indexes of corn gluten meal and corn protein concentrate A

[0040]

[0041] It can be seen from the results in Table 1 that the crude protein and protein digestibility of the corn protein concentrate prepared by the present invention are significantly improved, and the target of the index design is achieved.

[0042] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high digestibility corn protein concentrate, characterized in that: The crude protein content of the high-efficiency corn concentrated protein is ≥75%; and the digestibility of the broiler bionic protein is ≥85%.

2. A method for preparing high digestibility corn protein concentrate, characterized in that: The preparation method is used to prepare the high digestibility corn protein concentrate as claimed in claim 1.

3. The method for preparing the high digestibility corn protein concentrate according to claim 2, characterized in that: The preparation method comprises the following steps: Mix water and corn protein powder and add them to the enzymolysis tank, and add alkali to adjust the pH of the mixture of corn protein and water in the enzymolysis tank to 5.

0. The weight ratio of water to corn protein powder is 3-4:1, and the alkali includes sodium hydroxide, sodium carbonate and calcium hydroxide; Add amylase and saccharifying enzyme into the enzymolysis tank and stir to perform the first enzymolysis; The material obtained after the stirring is filtered through a plate and frame filter press to obtain a filter cake; The filter cake and water are mixed and poured into an enzymolysis tank, and acidic protease is added into the enzymolysis tank and stirred to perform a second enzymolysis; The material obtained after the second enzymatic hydrolysis is dried, and the dried material is crushed to obtain corn protein concentrate. The drying temperature of the drying is 100-120° C., the drying time is 16-20 hours, and the moisture content of the material after drying is 5-8%.

4. The method for preparing the high digestibility corn protein concentrate according to claim 3, characterized in that: The enzymatic hydrolysis temperature of the first enzymatic hydrolysis is 58°C, and the stirring time is 4-6h; The enzymatic hydrolysis temperature of the second enzymatic hydrolysis is 55° C., and the stirring time is 6 to 8 hours.

5. The method for preparing the high digestibility corn protein concentrate according to claim 3, characterized in that: The weight ratio of the amylase to the corn gluten powder is 3-5:1000, the weight ratio of the saccharifying enzyme to the corn gluten powder is 4-6:10000, and the weight ratio of the acid protease to the corn gluten powder is 3-5:1000; The enzymatic activity of the amylase is 20000 U / g, the enzymatic activity of the saccharifying enzyme is 200000 U / g, and the enzymatic activity of the acidic protease is 200000 U / g.

6. The method for preparing the high digestibility corn protein concentrate according to claim 3, characterized in that: The water content of the filter cake is 45-55%, and the weight ratio of the filter cake to water is 100:60-70.

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