A method for preparing a high-protein corn germ meal jet-mixed feed, a jet-mixed feed and corn germ meal

Abstract

The application discloses a preparation method of high-protein corn germ meal and corn steep liquor mixed feed, the mixed feed and the corn germ meal, and belongs to the technical field of feed processing. The preparation method comprises the following steps: crushing corn germ, and then screening and collecting corn germ powder; and mixing the corn germ powder with corn steep liquor at a mass ratio of 1:2.5 to 1:3, wherein the mixing temperature is 50-60 DEG C, the stirring speed is 50-100 rpm, and the stirring time is controlled to be 2-3 h, so as to obtain corn germ meal and corn steep liquor mixed feed with a water content of less than or equal to 48%. According to the application, the mixing ratio of the corn steep liquor is greatly increased, and accurate temperature control and stirring parameters are used, so that the soluble protein in the corn steep liquor and the corn germ powder are fully combined; the water content of the obtained corn germ meal and corn steep liquor mixed feed meets the feeding requirements of a drying device; the protein content of the finished product after drying can reach 28%-32%, the nutritional requirements of most poultry animals can be met, the process is simple and controllable, and the application is suitable for industrial production.

Description

Technical Field

[0001] This invention relates to the field of feed processing technology, specifically to a method for preparing a high-protein corn germ meal spray-mixed feed, the spray-mixed feed, and the corn germ meal. Background Technology

[0002] Corn germ meal is the residue after corn oil extraction from corn germ, a major byproduct of corn oil mills. It is a highly nutritious food primarily composed of corn fiber and protein, typically containing 17% crude protein, 6.5% crude fiber, 5.9% crude ash, and 54.8% nitrogen-free extract. Currently, commercially available corn germ meal is usually produced by spraying corn slurry (from corn starch production) back onto corn germ meal, followed by drying. This spraying process can increase the protein content of the corn germ meal to some extent. A typical spraying ratio (the mass ratio of corn germ meal to corn slurry) is 1:1.1 to 1:1.4, resulting in a protein content of 23% to 24% for the sprayed corn germ meal.

[0003] However, with the increasing demands for nutritional quality in the feed industry, a protein content of 23%–24% is no longer sufficient to meet the nutritional needs of most poultry. Therefore, how to further increase the protein content of spray-dried corn germ meal has become a pressing technical problem to be solved in this field.

[0004] To increase the protein content or improve the quality of spray-dried germ meal, various attempts have been made by those skilled in the art. For example, patent document CN117502562A uses a multi-strain fermentation method with yeast, Lactobacillus acidophilus, and white-rot fungi to increase protein content. However, the fermentation process is complex and time-consuming, and the residue of fermentation strains may pose a biosafety risk, making it unsuitable for large-scale industrial production. Patent document CN113973998A uses a "fermentation + masking" method, which improves product palatability by adding flavoring agents, sweeteners, and other masking agents. However, in addition to the inherent defects of fermentation methods, the masking agents have poor stability and are prone to failure, failing to fundamentally solve the problem. Furthermore, some studies have attempted to increase protein content through enzymatic hydrolysis, such as patent CN103222594B which uses mesophilic α-amylase for enzymatic hydrolysis. However, the product target of this process is instant food, which is different from the target of the feed-grade spray-dried germ meal in this application. Moreover, it involves complex enzymatic hydrolysis and homogenization steps, resulting in high production costs and making it unsuitable for large-scale production of feed-grade spray-dried germ meal.

[0005] Given the inherent limitations of the aforementioned technical approaches, those skilled in the art have attempted to increase the protein content of spray-dried germ meal by directly increasing the amount of corn steep liquor added. For instance, patent document CN222622113U discloses a corn germ meal slurry drying system. By increasing the corn steep liquor addition ratio from 1:1.5 to 1:2.5, and combining this with static reaction and two-stage drying processes, the protein content of the slurry-added germ meal was successfully increased to 28%. However, while simply increasing the amount of corn steep liquor theoretically increases protein content, it introduces new technical challenges: corn steep liquor typically has a moisture content of around 60%. Significantly increasing the spray ratio leads to a sharp increase in the total moisture content and viscosity of the material. Furthermore, sufficient space is required for the mixture to complete the wetting and absorption process, placing immense pressure on subsequent drying processes and potentially preventing proper drying, severely impacting production efficiency and product quality. Therefore, how to increase the spray ratio to enhance protein content while ensuring the material retains good processing properties remains a long-standing technical challenge for those skilled in the art. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing a high-protein corn germ meal spray-mixed feed, the spray-mixed feed and the corn germ meal. By precisely controlling the combination of the slurry addition ratio and mixing process parameters, the protein content is significantly increased while ensuring the uniformity and flowability of the material, creating favorable conditions for subsequent drying processes.

[0007] The specific technical solution of this invention is as follows: In a first aspect, the present invention provides a method for preparing a high-protein corn germ meal spray-mixed feed, comprising the following steps: S1. Raw material pretreatment: After crushing the corn germ, the corn germ powder is collected by sieving. S2. Precise mixing: The corn germ powder and corn slurry are mixed at a mass ratio of 1:2.5 to 1:3. The mixing temperature is 50 to 60 ℃, the stirring speed is 50 to 100 rpm, and the stirring time is controlled at 2 to 3 hours to obtain a corn germ meal spray-mixed feed with a moisture content of ≤48%.

[0008] Furthermore, in step S1, the particle size of the corn germ powder is 20-40 mesh.

[0009] Furthermore, in step S1, the moisture content of the corn germ is ≤10%.

[0010] Furthermore, in step S2, the water content of the corn syrup is ≥60%.

[0011] Further, in step S2, the mixing ratio of the corn germ powder to the corn syrup is 1:2.8 to 1:3.

[0012] Furthermore, in step S2, the mixing temperature is 55 ℃, the stirring speed is 75 rpm, and the stirring time is 2 h.

[0013] Furthermore, in step S2, the mixing temperature is 50 ℃, the stirring speed is 100 rpm, and the stirring time is 3 h.

[0014] Furthermore, in step S2, the mixing temperature is 60 ℃, the stirring speed is 50 rpm, and the stirring time is 2 h.

[0015] Secondly, the present invention provides a corn germ meal spray-mixed feed, which is prepared by the above-mentioned method for preparing high-protein corn germ meal spray-mixed feed.

[0016] Thirdly, the present invention provides a corn germ meal, which is obtained by spraying and mixing the above-mentioned corn germ meal with feed and drying it.

[0017] Beneficial effects This invention provides a method for preparing a high-protein corn germ meal spray-mixed feed, the spray-mixed feed, and the corn germ meal. Compared with the prior art, it has the following significant advantages: (1) The present invention adopts a precise pulping control method to control the ratio of germ to corn pulp at 1:2.5~1:3, which significantly improves the protein content of sprayed germ meal, which is much higher than the protein content of commercially available sprayed germ meal, and can meet the nutritional needs of most poultry animals.

[0018] (2) This invention optimizes the combination of parameters such as mixing temperature, stirring speed, and stirring time to ensure that corn steep liquor and corn germ are fully and uniformly mixed, allowing nutrients such as soluble proteins, soluble sugars, and amino acids in the corn steep liquor to fully penetrate into the germ meal, rather than just remaining on the surface. This not only improves the uniformity and stability of protein content but also improves the flowability of the material, creating favorable conditions for subsequent drying processes and effectively reducing the risk of pipe sticking during the subsequent drying process.

[0019] (3) By utilizing the batching process, the present invention accurately weighs each ingredient in the formula and can customize the formula according to market needs and customer requirements, ensuring the flexibility of the process and ensuring the feasibility and economy of the subsequent co-current spray drying process while guaranteeing high protein content.

[0020] (4) The preparation method provided by the present invention is simple and does not require fermentation strains or masking agents or other additives. It avoids the problems of complex fermentation process, long time consumption, and strain residue risk, as well as the problems of poor stability and easy failure of masking agents. It is suitable for large-scale industrial production and meets the requirements of green health and economy. Detailed Implementation

[0021] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation methods and typical parameters of the present invention, and are not intended to limit the parameter range described in the present invention. Reasonable variations derived therefrom are still within the protection scope of the present invention.

[0022] It should be noted that the endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0023] Unless otherwise defined, all terms, symbols, and other scientific terms used herein are intended to have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In some instances, terms having a conventional meaning are defined herein for clarification or ease of reference, and such definitions should not be construed as indicating a significant difference from conventional understanding in the art. The technical methods described or referenced herein are generally well understood by those skilled in the art and employed by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents, and instruments shall be performed according to the manufacturer's instructions and parameters.

[0024] To address the shortcomings of existing technologies, the moisture content of corn syrup is typically around 60%. Significantly increasing the spraying ratio leads to a sharp increase in the total moisture content and viscosity of the material, placing immense pressure on subsequent drying processes and potentially preventing proper drying. This invention provides a method for preparing a high-protein corn germ meal spray-mixed feed, comprising the following steps: S1. Raw material pretreatment: After crushing the corn germ, the corn germ powder is collected by sieving. S2. Precise mixing: The corn germ powder and corn slurry are mixed at a mass ratio of 1:2.5 to 1:3. The mixing temperature is 50 to 60 ℃, the stirring speed is 50 to 100 rpm, and the stirring time is controlled at 2 to 3 h to obtain a corn germ meal spray-mixed feed with a moisture content of ≤48%.

[0025] The above-mentioned method for preparing high-protein corn germ meal spray-mixed feed involves crushing the corn germ to increase its surface area and disrupt its original particle structure, exposing the protein and fiber tissues of the corn germ. This provides a structural basis for sufficient contact and bonding with corn syrup in the subsequent process. Screening removes excessively coarse particles and impurities generated during the crushing process, ensuring uniform particle size of the material entering the spray-mixing stage. This guarantees that each unit mass of material has a similar specific surface area and adsorption capacity, laying the foundation for uniform spray-mixing.

[0026] By increasing the mass ratio of corn germ powder to corn steep liquor to 1:2.5~1:3, the absolute amount of corn steep liquor rich in soluble protein and nitrogenous substances is significantly increased, thereby achieving a significant improvement in protein content from the source of the material formulation. Controlling the mixing temperature to 50~60 ℃ can reduce the viscosity and surface tension of the corn steep liquor, improve its fluidity, and make it easier for the corn steep liquor to penetrate into the internal pores of the corn germ powder, achieving deep and uniform bonding, rather than just remaining on the particle surface. At the same time, it accelerates the thermal motion of solute molecules such as soluble protein and soluble sugar in the corn steep liquor, promoting their adsorption and bonding with the surface of the germ powder, and shortening the time required to achieve uniform mixing.

[0027] At spray ratios as high as 1:2.5 to 1:3, the absolute amount of corn syrup added is very large, resulting in a material system characterized by high moisture content and high viscosity. A rotation speed of 50 to 100 rpm provides sufficient shear force and turbulence intensity, enabling rapid and uniform mixing of a large amount of corn syrup and germ powder on a macroscopic scale within the reactor. This speed also provides moderate shear force to evenly disperse the corn syrup around each germ powder particle, ensuring that each particle is coated with a slurry layer of the same thickness, thus guaranteeing the uniformity of protein content in the final product. Simultaneously, the medium-high speed stirring at 50 to 100 rpm effectively prevents the germ powder particles from agglomerating or settling due to gravity in the large amount of slurry, maintaining the suspension stability and flowability of the spray-mixed feed.

[0028] Under specific temperature conditions of 50-60 ℃ and rotation speed of 50-100 rpm, the adsorption and permeation of soluble substances in corn steep liquor from the liquid phase to the surface of the solid phase (germ powder) requires sufficient time to reach equilibrium. A time window of 2-3 hours ensures the full completion of the mass transfer process and avoids unnecessary energy consumption and efficiency reduction caused by excessive stirring.

[0029] By controlling the moisture content of the sprayed feed mixture to below 48%, and combining the synergistic effect of the aforementioned temperature and stirring parameters, the sprayed feed mixture is ensured to have pumpable and atomizable fluidity, overcoming the technical dilemma of "inability to dry normally" caused by increasing the spraying ratio in the existing technology.

[0030] In summary, the above-mentioned method for preparing high-protein corn germ meal spray-mixed feed achieves an increase in protein content at the source through a high spray ratio. Furthermore, by precisely controlling the temperature, stirring speed, and stirring time, it significantly improves the protein content while ensuring the uniformity and flowability of the material, creating favorable conditions for subsequent drying processes.

[0031] In one possible implementation, in step S1, the corn germ powder has a particle size of 20-40 mesh. This particle size range ensures that each unit mass of material has a similar specific surface area, making the adsorption capacity of each particle during spraying more consistent, thereby achieving uniformity in the protein content of the finished product. Simultaneously, this particle size range provides good flowability, facilitating subsequent mixing, stirring, and pneumatic conveying, thus providing process assurance for continuous industrial production.

[0032] In one possible implementation, in step S1, the moisture content of the corn germ is ≤10%. Controlling the moisture content of the corn germ to below 10% gives the germ powder a stronger water absorption capacity and adsorption driving force, enabling it to more fully absorb soluble nutrients from the corn steep liquor, thus achieving efficient enrichment of nutrients such as protein from the liquid phase to the solid phase.

[0033] In one possible implementation, in step S2, the water content of the corn steep liquor is ≥60%. A water content of ≥60% ensures, on the one hand, that the corn steep liquor has good fluidity, enabling it to fully contact and mix with the germ powder; on the other hand, the high water content means that the dissolved soluble proteins and nitrogenous substances are not excessively concentrated or denatured, retaining optimal biological activity and dispersion, which is beneficial for uniform adsorption onto the surface of the germ powder during the mixing process.

[0034] In one possible implementation, in step S2, the mixing ratio of the corn germ powder to the corn steep liquor is 1:2.8 to 1:3. This mixing ratio ensures the most sufficient addition of corn steep liquor, maximizing the utilization of soluble proteins and nitrogenous substances in the corn steep liquor, resulting in a final corn germ meal product with a protein content exceeding 30%.

[0035] In one possible implementation, in step S2, the mixing temperature is 55 ℃, the stirring speed is preferably 75 rpm, and the stirring time is preferably 2 h. A mixing temperature of 55 ℃ effectively reduces the viscosity and surface tension of the corn steep liquor to promote mass transfer while completely avoiding the risk of protein thermal denaturation. A stirring speed of 75 rpm provides moderate shear force, achieving both macroscopic uniform mixing and microscopic dispersion of the materials without causing excessive heating or foaming due to excessive shear. A stirring time of 2 h ensures that the adsorption and permeation between the solid and liquid phases reach a sufficient balance. These three factors achieve optimal synergistic effects at this preferred point, resulting in a spray-mixed feed with a moisture content of 47.9% and a finished product protein content as high as 32.0%. The material is non-viscous, does not separate into layers, and has good flowability, making it the optimal choice for balancing protein content, process efficiency, and processability.

[0036] In one possible implementation, in step S2, the mixing temperature is 50 °C, the stirring speed is 100 rpm, and the stirring time is 3 h. While the lower temperature of 50 °C results in a slightly weaker mass transfer driving force, this is compensated for by extending the stirring time to 3 h and increasing the stirring speed to 100 rpm. The higher stirring speed provides stronger shear forces and turbulence intensity, enabling finer dispersion of the corn steep liquor in the germ powder, particularly effective in preventing agglomeration when processing finer particle sizes. The longer stirring time ensures the full completion of the mass transfer process under low-temperature conditions.

[0037] In one possible implementation, in step S2, the mixing temperature is 60 °C, the stirring speed is 50 rpm, and the stirring time is 2 h. The relatively high temperature of 60 °C significantly reduces the viscosity and surface tension of the corn syrup, giving the syrup good fluidity and permeability. Therefore, the stirring speed can be reduced to 50 rpm, which is sufficient to achieve thorough mixing of the materials. This combination has the lowest energy consumption and a moderate mixing time, making it economical. The higher temperature promotes molecular thermal motion and accelerates the adsorption rate of soluble proteins at the solid-liquid interface, achieving a good mixing effect in a shorter time.

[0038] Secondly, a corn germ meal spray-dried mixed feed is provided, prepared by the aforementioned method for preparing high-protein corn germ meal spray-dried mixed feed. The corn germ meal spray-dried mixed feed prepared by the aforementioned method has a uniform color, is not layered, and is free of lumps. This ensures that nutrients are evenly distributed in the liquid phase and fully adsorbed onto the surface of the solid particles, while also meeting the process requirements of subsequent spray drying equipment for the flowability and atomization characteristics of the feed material. As a semi-finished product, this corn germ meal spray-dried mixed feed can be directly supplied to downstream drying processes, exhibiting good industrial intermediate product properties and storage stability.

[0039] Thirdly, a corn germ meal is provided, which is obtained by drying the above-mentioned corn germ meal spray-mixed feed. The finished corn germ meal obtained by drying the above-mentioned spray-mixed feed has a protein content as high as 28% to 32%, which is far superior to similar products on the market and can fully meet the nutritional needs of poultry, ruminants and other animals for different grades of protein feed ingredients.

[0040] The technical solution of the present invention will be further described below with reference to specific embodiments and comparative examples. All reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing. The instruments used in the embodiments are also commercially available.

[0041] Example 1 This embodiment provides a method for preparing a high-protein corn germ meal spray-mixed feed, including the following steps: S1. Raw Material Pretreatment: Take corn germ, whose moisture content is found to be 8.5%. Grind the corn germ in a grinder, pass it through a 40-mesh sieve, and collect the corn germ powder with a size smaller than 40 mesh. Take corn slurry produced during corn starch production, whose moisture content is found to be 60%.

[0042] S2. Precise Mixing: Weigh 10 kg of corn germ powder from step S1 and place it in a reaction vessel. Weigh 30 kg of corn syrup with a moisture content of 60% (the mass ratio of corn germ powder to corn syrup is 1:3) and place it in the same reaction vessel. Set the mixing temperature of the reaction vessel to 55 ℃ and the stirring speed to 75 rpm, start stirring, and continue the reaction for 2 hours. After the reaction is complete, a corn germ meal spray-mixed feed is obtained.

[0043] Performance testing of corn germ meal spray-mixed feed According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 26.0%.

[0044] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 47.9%, which meets the requirement of ≤48% moisture content.

[0045] The corn germ meal spray-mixed feed has a uniform color, is a uniform slurry-like fluid, has no stratification, good fluidity, and no obvious clumping or excessively high viscosity. This indicates that under this parameter combination, the high spray ratio material achieves good mixing uniformity.

[0046] Example 2 This embodiment provides a method for preparing a high-protein corn germ meal spray-mixed feed, including the following steps: S1. Raw Material Pretreatment: Corn germ was taken, and its moisture content was found to be 9.2%. The corn germ was then pulverized in a grinder and passed through a 40-mesh sieve. Corn germ powder with a size smaller than 40 mesh was collected. Corn slurry produced during corn starch production was taken, and its moisture content was found to be 60%.

[0047] S2. Precise Mixing: Weigh 10 kg of corn germ powder from step S1 and place it in a reaction vessel. Weigh 25 kg of corn syrup with a moisture content of 60% (the mass ratio of corn germ powder to corn syrup is 1:2.5) and place it in the same reaction vessel. Set the mixing temperature of the reaction vessel to 50 ℃ and the stirring speed to 100 rpm, start stirring, and continue the reaction for 3 hours. After the reaction is complete, a corn germ meal spray-mixed feed is obtained.

[0048] Performance testing of corn germ meal spray-mixed feed According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 25.7%.

[0049] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 42.9%, which meets the requirement of ≤48% moisture content.

[0050] The corn germ meal spray-mixed feed has a uniform color, is a uniform slurry-like fluid, has no stratification, good fluidity, and no obvious clumping or excessively high viscosity. This indicates that under this parameter combination, the high spray ratio material achieves good mixing uniformity.

[0051] Example 3 This embodiment provides a method for preparing a high-protein corn germ meal spray-mixed feed, including the following steps: S1. Raw Material Pretreatment: Corn germ was taken, and its moisture content was found to be 7.8%. The corn germ was then pulverized in a grinder and passed through a 40-mesh sieve. Corn germ powder with a size smaller than 40 mesh was collected. Corn slurry produced during corn starch production was taken, and its moisture content was found to be 60%.

[0052] S2. Precise Mixing: Weigh 10 kg of corn germ powder from step S1 and place it in a reaction vessel. Weigh 28 kg of corn syrup with a moisture content of 60% (the mass ratio of corn germ powder to corn syrup is 1:2.8) and place it in the same reaction vessel. Set the mixing temperature of the reaction vessel to 60 ℃ and the stirring speed to 50 rpm, start stirring, and continue the reaction for 2 hours. After the reaction is completed, a corn germ meal spray-mixed feed is obtained.

[0053] Performance testing of corn germ meal spray-mixed feed According to GB 5009.5-2016, the protein content of corn germ sprayed feed was tested and found to be 25.9%.

[0054] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 44.2%, which meets the requirement of ≤48% moisture content.

[0055] The corn germ meal spray-mixed feed has a uniform color, is a uniform slurry-like fluid, has no stratification, good fluidity, and no obvious clumping or excessively high viscosity. This indicates that under this parameter combination, the high spray ratio material achieves good mixing uniformity.

[0056] Example 4 This embodiment provides a corn germ meal, which is prepared through the following steps: D1. Pre-drying: The corn germ meal spray-dried mixture prepared in Example 1 was placed in a co-current spray dryer for pre-drying at a drying temperature of 60 ℃ for 3 h to obtain a spray-dried germ meal semi-finished product. Its moisture content was tested according to GB / T 6435-2014. The moisture content of the spray-dried germ meal semi-finished product was reduced to 33.5%, and the viscosity of the material was low, with no black paste particles generated.

[0057] D2. Deep drying: The sprayed germ meal semi-finished product obtained in step D1 is transferred to a tube bundle dryer for deep drying at a temperature of 100 ℃ for 1 h to obtain sprayed germ meal solids. The moisture content is tested according to GB / T 6435-2014. The moisture content of the sprayed germ meal solids is reduced to 12.0%, and the material does not stick to the tube and no obvious black paste particles are found.

[0058] D3. Low-temperature grinding: The sprayed corn germ meal solid obtained in step D2 is put into a low-temperature grinder, the temperature is set at 10℃ and the cooling time is 2 hours. The 40-mesh sprayed corn germ meal product is collected, and its protein content is tested according to GB 5009.5-2016. The test results show that the sprayed corn germ meal has a uniform color and its protein content is as high as 32.0%, which is much higher than the protein content of commercially available sprayed corn germ meal (23%~24%), and can meet the nutritional needs of most poultry animals.

[0059] Example 5 This embodiment provides a corn germ meal, which is prepared through the following steps: D1. Pre-drying: The corn germ meal spray-dried mixture prepared in Example 2 was placed in a co-current spray dryer for pre-drying at a drying temperature of 55 ℃ for 2 hours to obtain a spray-dried germ meal semi-finished product. Its moisture content was tested according to GB / T 6435-2014. The moisture content of the spray-dried germ meal semi-finished product was reduced to 32.0%, and the viscosity of the material was low, with no black paste particles generated.

[0060] D2. Deep drying: The sprayed germ meal semi-finished product obtained in step D1 is transferred to a tube bundle dryer for deep drying at a temperature of 90 ℃ for 1 h to obtain sprayed germ meal solids. The moisture content is tested according to GB / T 6435-2014. The moisture content of the sprayed germ meal solids is reduced to 10.1%, and the material does not stick to the tube and no obvious black paste particles are found.

[0061] D3. Low-temperature grinding: The sprayed corn germ meal solid obtained in step D2 is put into a low-temperature grinder, the temperature is set at 5℃ and the cooling time is 3 hours. The 40-mesh sprayed corn germ meal product is collected, and its protein content is tested according to GB 5009.5-2016. The test results show that the sprayed corn germ meal has a uniform color and its protein content is as high as 28.1%, which is much higher than the protein content of commercially available sprayed corn germ meal (23%~24%), and can meet the nutritional needs of most poultry animals.

[0062] Example 6 This embodiment provides a corn germ meal, which is prepared through the following steps: D1. Pre-drying: The corn germ meal spray-dried mixture prepared in Example 3 was placed in a co-current spray dryer for pre-drying at a drying temperature of 50 ℃ for 3 h to obtain a spray-dried germ meal semi-finished product. Its moisture content was tested according to GB / T 6435-2014. The moisture content of the spray-dried germ meal semi-finished product was reduced to 33.5%, and the viscosity of the material was low, with no black paste particles generated.

[0063] D2. Deep drying: The sprayed germ meal semi-finished product obtained in step D1 is transferred to a tube bundle dryer for deep drying at a temperature of 95 ℃ for 1 h to obtain sprayed germ meal solids. The moisture content is tested according to GB / T 6435-2014. The moisture content of the sprayed germ meal solids is reduced to 11.3%, and the material does not stick to the tube and no obvious black paste particles are found.

[0064] D3. Low-temperature grinding: The sprayed corn germ meal solid obtained in step D2 is put into a low-temperature grinder, the temperature is set to 0℃ and the cooling time is 2 hours. The 40-mesh sprayed corn germ meal product is collected, and its protein content is tested according to GB 5009.5-2016. The test results show that the sprayed corn germ meal has a uniform color and its protein content is as high as 30.5%, which is much higher than the protein content of commercially available sprayed corn germ meal (23%~24%), and can meet the nutritional needs of most poultry animals.

[0065] Comparative Example 1 This comparative example provides a corn germ meal, which is prepared through the following steps: S1. Raw material pretreatment: Same as in Example 1.

[0066] S2. Precise Addition of Slurry: Weigh 10 kg of corn germ powder from step S1 and place it in the reactor. Weigh 14 kg of corn slurry with a moisture content of 60% (the mass ratio of corn germ powder to corn slurry is 1:1.4) and place it in the same reactor. Set the mixing temperature of the reactor to 55 ℃ and the stirring speed to 75 rpm, start stirring, and continue the reaction for 2 hours. After the reaction is complete, a corn germ meal spray-mixed feed is obtained.

[0067] S3. Drying: The corn germ meal spray-dried mixture obtained in step S2 is placed in a tube bundle dryer and dried at 180 ℃ for 3 hours to obtain spray-dried corn germ meal solids. After drying, a large amount of germ meal exhibited "sticking to the tube bundles" phenomenon, accompanied by the formation of a large number of black paste particles.

[0068] S4. Crushing: The sprayed corn germ meal obtained in step S3 is crushed into solid powder, and 40-mesh powder is collected. The protein content of the finished sprayed corn germ meal is tested according to GB5009.5-2016. The test results show that the sprayed corn germ meal is dark in color and has a protein content of only 24.0%, which cannot meet the nutritional needs of most poultry.

[0069] Comparative Example 2 This comparative example provides a corn germ meal, which is prepared through the following steps: S1. Raw material pretreatment: Same as in Example 2.

[0070] S2. Precise Addition of Slurry: Weigh 10 kg of corn germ powder from step S1 and place it in the reactor. Weigh 12 kg of corn slurry with a moisture content of 60% (the mass ratio of corn germ powder to corn slurry is 1:1.2) and place it in the same reactor. Set the mixing temperature of the reactor to 50 ℃ and the stirring speed to 75 rpm, start stirring, and continue the reaction for 2 hours. After the reaction is complete, a corn germ meal spray-mixed feed is obtained.

[0071] S3. Drying: The corn germ meal spray-mixed feed obtained in step S2 was placed in a tube bundle dryer and dried at 180 ℃ for 3 hours to obtain spray-mixed corn germ meal solids. After drying, the "sticking to tube bundles" phenomenon also occurred, accompanied by the formation of a large number of black paste particles.

[0072] S4. Crushing: The sprayed corn germ meal obtained in step S3 is crushed into solid powder, and 40-mesh powder is collected. The protein content of the finished sprayed corn germ meal is tested according to GB5009.5-2016. The test results show that the sprayed corn germ meal is dark in color and has a protein content of only 23.4%, which cannot meet the nutritional needs of most poultry.

[0073] Comparative Example 3 This comparative example provides a corn germ meal, which is prepared through the following steps: S1. Raw material pretreatment: Same as in Example 3.

[0074] S2. Precise Addition of Slurry: Weigh 10 kg of corn germ powder from step S1 and place it in the reactor. Weigh 11 kg of corn slurry with a moisture content of 60% (the mass ratio of corn germ powder to corn slurry is 1:1.1) and place it in the same reactor. Set the mixing temperature of the reactor to 60 ℃ and the stirring speed to 50 rpm, start stirring, and continue the reaction for 2 hours. After the reaction is completed, a corn germ meal spray-mixed feed is obtained.

[0075] S3. Drying: The corn germ meal spray-mixed feed obtained in step S2 was placed in a tube bundle dryer and dried at 180 ℃ for 3 hours to obtain spray-mixed corn germ meal solids. After drying, the "sticking to tube bundles" phenomenon also occurred, accompanied by the formation of a large number of black paste particles.

[0076] S4. Crushing: The sprayed corn germ meal obtained in step S3 is crushed into solid powder, and 40-mesh powder is collected. The protein content of the finished sprayed corn germ meal is tested according to GB5009.5-2016. The test results show that the sprayed corn germ meal is dark in color and has a protein content of only 23.0%, which cannot meet the nutritional needs of most poultry.

[0077] Comparative Example 4 This comparative example provides a method for preparing a corn germ meal spray-mixed feed. The only difference from Example 2 is that 15 kg of corn syrup with a moisture content of 60% is weighed out, and the other steps and processes are the same as in Example 2.

[0078] According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 24.8%, which is low and cannot meet the nutritional needs of most poultry.

[0079] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 36.0%, which meets the requirement of ≤48% moisture content.

[0080] Comparative Example 5 This comparative example provides a method for preparing a corn germ meal spray-mixed feed. The only difference from Example 2 is that 35 kg of corn syrup with a moisture content of 60% is weighed out, and the other steps and processes are the same as in Example 2.

[0081] According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 26.2%.

[0082] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 48.9%, which does not meet the requirement of ≤48% moisture content.

[0083] Comparative Example 6 This comparative example provides a method for preparing a corn germ meal spray-mixed feed, which differs from Example 3 only in that 38 kg of corn syrup with a moisture content of 60% is weighed, and all other steps and processes are the same as in Example 3.

[0084] According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 26.3%.

[0085] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 49.5%, which does not meet the requirement of ≤48% moisture content.

[0086] Comparative Example 7 This comparative example provides a method for preparing a corn germ meal spray-mixed feed. The only difference from Example 1 is that 40 kg of corn syrup with a moisture content of 60% is weighed out, and the other steps and processes are the same as in Example 1.

[0087] According to GB 5009.5-2016, the protein content of the corn germ meal sprayed feed was found to be 26.4%.

[0088] According to GB / T 6435-2014, the moisture content of the corn germ meal spray-mixed feed was tested and found to be 50.4%, which does not meet the requirement of ≤48% moisture content.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a high-protein corn germ meal spray-mixed feed, characterized in that, Includes the following steps: S1. Raw material pretreatment: After crushing the corn germ, the corn germ powder is collected by sieving. S2. Precise mixing: The corn germ powder and corn slurry are mixed at a mass ratio of 1:2.5 to 1:

3. The mixing temperature is 50 to 60 ℃, the stirring speed is 50 to 100 rpm, and the stirring time is controlled at 2 to 3 h to obtain a corn germ meal spray-mixed feed with a moisture content of ≤48%.

2. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S1, the particle size of the corn germ powder is 20-40 mesh.

3. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S1, the moisture content of the corn germ is ≤10%.

4. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S2, the water content of the corn syrup is ≥60%.

5. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S2, the mixing ratio of corn germ powder to corn syrup is 1:2.8 to 1:

3.

6. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S2, the mixing temperature is 55 ℃, the stirring speed is 75 rpm, and the stirring time is 2 h.

7. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S2, the mixing temperature is 50 ℃, the stirring speed is 100 rpm, and the stirring time is 3 h.

8. The method for preparing high-protein corn germ meal spray-mixed feed according to claim 1, characterized in that, In step S2, the mixing temperature is 60 ℃, the stirring speed is 50 rpm, and the stirring time is 2 h.

9. A corn germ meal spray-mixed feed, characterized in that, It is prepared by any one of the methods for preparing high-protein corn germ meal spray-mixed feed according to claims 1-8.

10. A corn germ meal, characterized in that, It is obtained by drying the corn germ meal spray-mixed feed as described in claim 9.