Fermented pig feed based on palm kernel meal and soybean meal and method for its preparation

Abstract

This invention belongs to the field of livestock and poultry fermented feed technology, and provides a fermented pig feed based on palm meal and soybean meal and its preparation method. By compounding porous palm meal granules I-A1, low-antigen soybean meal binding component I-B1, and composite coated granules I-AB in a dry-basis ratio, and employing fluidized bed spraying, conditioning granulation, and controlled-drying processes, a coordinated balance is achieved between high pore volume digestibility, coating and binding ability, and granule mechanical stability. This method is beneficial for improving the utilization state and granulation stability of acid-soluble proteins, reducing the influence of soy globulin and β-conglyzin, improving the uniformity of the finished product and the compatibility with spraying processing, and solving the problems of balancing the mechanical stability and high pore volume digestibility of porous fiber carrier granules, as well as the difficulty in simultaneously achieving coating and binding, spraying processing compatibility, and granulation stability with low-antigen soybean meal. It is suitable for the preparation of pig pellet feed and functional feed bases.

Description

Technical Field

[0001] This invention relates to the field of livestock and poultry fermented feed technology, specifically to a fermented pig feed based on palm meal and soybean meal and its preparation method. Background Technology

[0002] During the nursery and growth stages of piglets, pelleted feed not only needs to meet protein and energy requirements but also needs to maintain stable pellet mechanical stability and suitable digestibility during conditioning, pelleting, cooling, transportation, and feeding. Palm meal is a widely available and relatively cost-effective plant-based raw material with potential applications; however, without targeted processing, it is often difficult to simultaneously achieve both pellet skeletal function and high porosity digestibility. Soybean meal is an important protein source in pig feed, and in young pigs and those with sensitive intestines, it is even more important to balance low antigen content, high acid-soluble protein content, and good processing compatibility. As pelleted feed production becomes increasingly continuous, simply improving the nutritional status of a single raw material is no longer sufficient to meet actual needs. Developing technical solutions that simultaneously consider spray processing compatibility, coating and bonding capabilities, and pelleting stability, focusing on porous fiber carriers, binding components, and forming processes, has become an important direction for the research and development of fermented pig feed. Especially when palm meal replaces some conventional raw materials and soybean meal serves as the main plant protein, if a stable matching relationship cannot be established between the raw material structure and pellet formation, it will easily affect the uniformity of the finished product, the continuity of pelleting, and the end-feeding adaptability. Therefore, it is of great significance to develop fermented pig feed that has both nutritional improvement and pellet processing adaptability.

[0003] Existing technologies mostly focus on modifying single raw materials. For example, Chinese patent CN110591943A discloses a high-yield compound enzyme Bacillus subtilis strain, composition, and its application, emphasizing the improvement of palm meal utilization value through the interaction of microorganisms and compound enzymes. However, its technological focus remains on the fermentation treatment of palm meal as a single substrate, with insufficient attention to the balance between the mechanical stability of porous fiber carriers and the digestibility and accessibility of high-pore volume. Another example is Chinese patent CN111631312A, which discloses high-quality enzymatically fermented soybean meal, focusing on reducing antigenic proteins and increasing acid-soluble protein content. However, it emphasizes nutritional optimization at the soybean meal end, with insufficient system design for its role as a binding component in fluidized bed spraying, forming an outer coating layer and / or agglomerated binding layer, and improving pelleting stability. Especially in the context of pig pellet feed, the contradiction between simultaneously optimizing coating and binding forming capabilities and spraying processing adaptability remains prominent. Therefore, how to effectively couple porous palm meal particles with low-antigen soybean meal binding components in the same formulation and process system remains a key problem that existing technologies need to solve. Summary of the Invention

[0004] The purpose of this invention is to provide a fermented pig feed based on palm meal and soybean meal and its preparation method, which solves the problems in the prior art that it is difficult to simultaneously achieve the particle mechanical stability and high pore volume digestibility of porous fiber carriers, and the problems that it is difficult to simultaneously optimize the coating and binding ability, spraying processing adaptability and granulation stability of low antigen soybean meal components while achieving high acid solubility and low allergenicity of proteins.

[0005] Porous palm meal pellets I-A1 provide pore volume and pellet skeleton, while low-antigen soybean meal binding component I-B1 provides an outer coating layer and / or an agglomeration binding layer. The two work together in composite coated pellets I-AB to coordinate and balance high pore volume digestibility, coating and binding forming ability, spray processing adaptability and pelleting stability in the same system.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A fermented pig feed based on palm meal and soybean meal, comprising, by total dry weight of the final product, 20-40 wt% porous palm meal particles I-A1, 10-25 wt% low-antigen soybean meal binding component I-B1, 5-18 wt% composite coated particles I-AB, and the balance being corn, wheat or a mixture of corn and wheat.

[0008] The 20-40 wt% porous palm meal particles I-A1 and the 10-25 wt% low-antigen soybean meal binding component I-B1 are the portions of the final product that do not enter the composite coated particles I-AB. The composite coated particles I-AB are formed by another portion of the porous palm meal particles I-A1 and another portion of the low-antigen soybean meal binding component I-B1. The composite coated particles I-AB are mononuclear or multinuclear aggregated coated particles with one or more of the porous palm meal particles I-A1 as the core layer and the low-antigen soybean meal binding component I-B1 forming the outer coating layer or the agglomerated binding layer, or simultaneously forming the outer coating layer and the agglomerated binding layer.

[0009] Furthermore, the porous palm meal granules I-A1 have a pore volume of 0.15-0.45 cm³ / g, and their neutral detergent fiber content is reduced by 15-35% compared to the original palm meal used in preparing the porous palm meal granules I-A1.

[0010] The acid-soluble protein in the low-antigen soybean meal binding component I-B1 accounts for 15-35 wt% of its crude protein, and the total amount of glycinin and β-conglycinin is reduced by 70-95% compared with the original soybean meal used to prepare the low-antigen soybean meal binding component I-B1; the particle size of the composite coated particles I-AB after preparation and before addition to the fermented pig feed is 0.5-2.5 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 10-60 μm.

[0011] Furthermore, the porous palm meal granules I-A1 are obtained through the following steps:

[0012] A1. Mix palm meal with deionized water at a mass ratio of 100:(30-45);

[0013] A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1, wherein the amount of β-mannanase added is 0.05-0.30 wt%, the amount of xylanase added is 0.02-0.20 wt%, and the amount of protease added is 0.02-0.10 wt% relative to the mass of palm meal. The amounts added are based on the mass of commercial enzyme preparations. Enzymatic hydrolysis is carried out at 45-55℃ and pH 4.5-6.5 for 4-10 hours.

[0014] A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 10 g each. 6 -10 8 CFU / g and 10 5 -10 7 CFU / g, the inoculum amount is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 32-37℃ under aerobic conditions for 24-48h;

[0015] A4. The fermented product obtained in step A3 is dried at 55-65℃ until the moisture content is no more than 12wt%, pulverized and sieved to 0.3-1.0mm to obtain the porous palm meal particles I-A1.

[0016] Furthermore, the low-antigen soybean meal binding component I-B1 is prepared through the following steps:

[0017] B1. Mix soybean meal and deionized water at a mass ratio of 100:(25-40);

[0018] B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.05-0.30 wt% relative to the mass of soybean meal, the amount added being based on the mass of a commercial enzyme preparation, and enzymatic hydrolysis is performed at 40-55°C and pH 5.5-7.0 for 2-6 hours.

[0019] B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 10 g each. 6 -10 8 CFU / g and 10 5 -10 7CFU / g, the inoculum amount is based on the total mass of the fermented wet material, solid fermentation is carried out at 30-38℃ under aerobic conditions for 24-60h, and the final pH value of the fermentation is 4.5-6.0;

[0020] B4. The fermented product obtained in step B3 is dried at 50-60℃ until the moisture content is no more than 12wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1.

[0021] Furthermore, the composite coated particles I-AB are prepared through the following steps:

[0022] C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. The dry basis mass ratio of the porous palm meal particles I-A1 to the low-antigen soybean meal binder component I-B1 is 100:(20-80). The amount of deionized water added is adjusted to make the solid content of the coating slurry 45-75wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 5.0-7.0.

[0023] C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 by fluidized bed spraying under the conditions of air inlet temperature of 55-70℃ and material layer temperature of 35-45℃, to perform spray coating or spray granulation, and the spraying time is 20-60 minutes.

[0024] C3. The material obtained in step C2 is dried at 45-60℃ for 1-3 hours until the moisture content is 9-12wt% to obtain the composite coated particles I-AB, the thickness of the outer coating layer and / or the characteristic thickness of the agglomeration and bonding layer is 10-60μm, and the particle size is 0.5-2.5mm.

[0025] Furthermore, the fermented pig feed is pelleted feed with a pellet diameter of 2.0-6.0 mm and a finished product moisture content of 9-12 wt%.

[0026] As a concept of this invention, the present invention employs a combined design of porous palm meal pellets I-A1, low-antigen soybean meal binder I-B1, and composite coated pellets I-AB, primarily to enhance the mechanical stability of fermented pig feed pellets, high pore volume digestibility and accessibility, coating and binding ability, and spray processing adaptability. Porous palm meal pellets I-A1, after enzymatic hydrolysis and solid-state fermentation, function as both pore volume and pellet skeleton, providing more favorable digestible contact conditions for the final product. Low-antigen soybean meal binder I-B1, after enzymatic hydrolysis and solid-state fermentation, possesses both high levels of acid-soluble protein and low levels of glycinin and β-conglycinin, forming an outer coating layer and / or agglomeration binder layer within the composite coated pellets I-AB, improving coating and binding ability. The synergistic formulation of these three components in a dry-basis ratio ensures that digestibility, pellet mechanical stability, and subsequent pelleting stability are simultaneously achieved within the same system.

[0027] This invention also discloses a method for preparing fermented pig feed based on palm meal and soybean meal, comprising the following steps:

[0028] S1. Provides porous palm meal pellets I-A1;

[0029] S2. Provides low-antigen soybean meal binding component I-B1;

[0030] S3. Provides composite coated particles I-AB;

[0031] S4. The porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used to prepare the composite coated granules I-AB in step S3 are mixed with the composite coated granules I-AB provided in step S3 and corn, wheat or a mixture of corn and wheat according to the final product ratio, and the mixture is adjusted to a moisture content of 14-18 wt%. The mixture is then granulated at 65-75°C, cooled and dried to a finished product moisture content of 9-12 wt% to obtain the fermented pig feed.

[0032] Furthermore, the composite coated particles I-AB provided in step S3 are prepared by fluidized bed spraying, and the conditioning time in step S4 is 20-60s.

[0033] After granulation in step S4, the material temperature is cooled to 25-40℃.

[0034] Furthermore, the particle size D50 of the low-antigen soybean meal binding component I-B1 provided in step S2 is 50-300 μm.

[0035] Furthermore, the porous palm meal particles I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 are both obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis is prepared with a viable count of 10-1. 9-10 11 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a live cell count of 10-10. 8 -10 10 Commercial dry yeast (CFU / g)

[0036] Furthermore, the mass of palm meal, soybean meal, low-antigen soybean meal binding component and porous palm meal particles are all calculated on a dry basis. The actual amount of feed is converted to the corresponding dry basis mass based on the measured moisture content of the raw materials. The total mass of fermented wet material is the total mass of raw materials, deionized water, enzyme preparation, pH adjustment solution and bacterial agent after mixing. The initial moisture content of the original palm meal and original soybean meal is not higher than 12 wt%.

[0037] Furthermore, the solid content of the system after mixing palm meal and deionized water is 69-77 wt%, and the solid content of the system after mixing soybean meal and deionized water is 71-80 wt%. The solid content is calculated based on the dry basis weight of palm meal or soybean meal and the weight of added deionized water, respectively.

[0038] Furthermore, when mixing palm meal with deionized water and soybean meal with deionized water, mechanical stirring is used until the mixture is homogeneous.

[0039] Furthermore, β-mannanase, xylanase, and protease were all added directly using commercially available solid enzyme preparations and stirred evenly, with the enzyme activities of β-mannanase, xylanase, and protease being no less than 10,000 U / g, no less than 10,000 U / g, and no less than 50,000 U / g, respectively.

[0040] Furthermore, the amount of enzyme preparation added is recorded uniformly according to both the dry basis weight of the raw material and the actual weight of the enzyme preparation, and the corresponding amount of enzyme activity units added is recorded simultaneously.

[0041] Furthermore, in the enzymatic hydrolysis step, the pH of the system is adjusted by adding 1-3 mol / L hydrochloric acid solution or 1-3 mol / L sodium hydroxide solution dropwise. During the enzymatic hydrolysis process, the pH is measured every 0.5-2 hours and the adjusting solution is added to maintain the target pH range.

[0042] Furthermore, the pH during solid-state enzymatic hydrolysis or fermentation was determined by preparing a slurry at a mass ratio of 1:5 between the sample and deionized water, and measuring the pH at 25°C using a calibrated pH meter.

[0043] Furthermore, the enzymatic hydrolysis step is carried out in a closed or semi-closed container, and the water loss of the system during enzymatic hydrolysis does not exceed 10 wt% of the initial total water added.

[0044] Furthermore, the viable count of Bacillus subtilis commercial powder is 10. 9 -10 11 The viable count of commercial brewing yeast (CFU / g) is 10. 8 -10 10CFU / g, the actual amount of commercial microbial agent added is calculated by multiplying the target inoculum amount by the total mass of the fermented wet substrate and then dividing by the number of live bacteria in the commercial microbial agent.

[0045] Furthermore, the inoculated material is spread evenly in an open fermentation pan or perforated tray with a layer thickness of 3-8cm, and turned over every 4-8 hours under natural ventilation conditions; or it is placed in a solid fermenter and continuously or intermittently forced to ventilate at an aeration rate of 0.2-1.0L / min·kg wet material.

[0046] Furthermore, the fermentation endpoint of soybean meal was determined by the pH stability range. The fermentation endpoint was defined as the system pH stabilized in the range of 4.5-6.0 and did not decrease for 4-8 hours.

[0047] Furthermore, the porous palm meal fermentation material is dried by hot air drying at 55-65℃ and hot air flow rate of 0.5-2.0m / s, with a single layer thickness of 1-5cm. After drying, it is crushed and sieved using a hammer mill to collect particles with a particle size of 0.3-1.0mm.

[0048] Furthermore, the low-antigen soybean meal fermentation product is dried by hot air drying at 50-60℃ and hot air flow rate of 0.5-2.0m / s, with a single layer thickness of 1-5cm. After drying, it is pulverized by hammer mill or needle mill and sieved to control the particle size D50 of the obtained low-antigen soybean meal binding component to be 50-300μm.

[0049] Furthermore, the particle size D50 of the low-antigen soybean meal binding component was determined by laser particle size distribution. Before the determination, the samples were ultrasonically dispersed in anhydrous ethanol or deionized water for 1-5 min, and the same dispersion medium was used for the same group of comparative samples.

[0050] Furthermore, acid-soluble protein was determined by extraction with 10wt% trichloroacetic acid, and crude protein content was determined by Kjeldahl nitrogen determination and converted by multiplying nitrogen content by 6.25. Both acid-soluble protein content and crude protein content were calculated based on the dry basis of the sample. During extraction, 10-20 mL of extraction solution was added per 1 g of dry sample, and the sample was extracted at 20-30℃ for 20-60 min. The supernatant was then centrifuged and the sample was analyzed.

[0051] Furthermore, the neutral detergent fiber content was determined using the VanSoest method. All neutral detergent fiber contents were calculated on a dry basis. The neutral detergent fiber reduction rate was calculated by subtracting the neutral detergent fiber content of porous palm meal particles from the original palm meal neutral detergent fiber content, dividing by the original palm meal neutral detergent fiber content, and then multiplying by 100%.

[0052] Furthermore, the total amount of daidzein and β-congaidzein was determined by ELISA or SDS-PAGE. The comparison between the original soybean meal and the binding component of the low-antigen soybean meal should use the same detection method and the same calibration system. The total amount of related proteins is calculated on a dry basis. The reduction rate is calculated by subtracting the total amount of daidzein and β-congaidzein in the binding component of the low-antigen soybean meal from the total amount of daidzein and β-congaidzein in the original soybean meal, dividing by the total amount of daidzein and β-congaidzein in the original soybean meal, and then multiplying by 100%.

[0053] Furthermore, the pore volume of porous palm meal particles was determined by nitrogen adsorption-desorption method. Before the measurement, the samples were pretreated in vacuum at 80-105℃ for 4-12 hours, and the pore volume was calculated on a dry basis.

[0054] Furthermore, the coating slurry is prepared by adding 33-122 parts of deionized water to 100 parts of dry weight of low antigen soybean meal binding component, and mechanically stirring at 300-800 rpm for 10-30 minutes until uniform.

[0055] Furthermore, the solid content of the coating slurry is calculated based on the dry weight of the low-antigen soybean meal binder and the weight of added deionized water, with an apparent viscosity of 500-5000 mPa·s. This apparent viscosity is achieved at 25°C and a shear rate of 100 s⁻¹. -1 Determined under the specified conditions.

[0056] Furthermore, the pH of the coating slurry is adjusted to 5.0-7.0 using a 1-3 mol / L hydrochloric acid solution or a 1-3 mol / L sodium hydroxide solution, and the slurry is continuously stirred during the spraying process to maintain its uniformity.

[0057] Furthermore, the spraying step is carried out using a fluidized bed top spraying or bottom spraying method. The spraying rate is 5-30 mL / min per kilogram of dry substrate to be coated, and is matched and set according to the target dry substrate mass ratio of the core layer and the outer coating layer and / or agglomerated bonding layer, the solid content of the coating slurry, and the spraying time. The atomization pressure is 0.1-0.3 MPa, the bed wind speed is 0.5-2.0 m / s, the loading amount is 0.5-5 kg, and the distance from the spray gun outlet to the bed surface is 10-25 cm.

[0058] Furthermore, the sprayed material is dried at 45-60℃ for 1-3 hours until the moisture content is 9-12wt%, and after cooling, particles with a diameter of less than 0.5mm and greater than 2.5mm are screened out.

[0059] Furthermore, the thickness of the outer coating layer and / or the characteristic thickness of the agglomeration and bonding layer of the composite coated particles were determined by observing the cross-section of the particles using a scanning electron microscope. For particles with an outer coating layer, the local thickness of the coating layer was measured. For particles with interparticle bonding bridge structures, the characteristic thickness of the bonding bridge at the connection interface was measured. 20-50 particle cross-sections or bonding bridge locations were randomly measured and the average value was taken.

[0060] Furthermore, the particle size of the composite coated particles was determined by sieving, with the sieve particle size range of 0.5-2.5 mm as the qualified particle size. Laser particle size distribution was used as an auxiliary characterization method and expressed as volume distribution D50.

[0061] Furthermore, the coating weight gain rate of the composite coated particles is 20-80%. The coating weight gain rate is determined by the dry basis weight gain method, which is the dry basis weight of the composite coated particles after spraying and drying minus the dry basis weight of the coated substrate before spraying, then divided by the dry basis weight of the coated substrate before spraying and multiplied by 100%.

[0062] Furthermore, when the dry basis mass ratio of the core layer to the outer coating layer and / or agglomerated adhesive layer formed by the low-antigen soybean meal binder in the composite coated particles is 100:(20-80), the outer coating layer and / or agglomerated adhesive layer can form a continuous shell, a discontinuous shell, or an interparticle adhesive bridge structure. Moreover, the core layer, outer coating layer, and agglomerated adhesive layer in the composite coated particles are not included in the porous palm meal particles and low-antigen soybean meal binder that do not enter the composite coated particles.

[0063] Furthermore, when using a mixture of corn and wheat, the mass ratio of corn to wheat is 1:9 to 9:1.

[0064] Furthermore, in the finished product granulation step, the material is steam-conditioned until the moisture content is 14-18wt%, and then granulated by ring die or flat die. The conditioning temperature is 65-75℃, the conditioning time is 20-60s, and the diameter of the finished particles is 2.0-6.0mm.

[0065] Furthermore, the cooling after granulation adopts countercurrent cooling or co-current cooling, with a cooling endpoint temperature of 25-40℃, a finished product moisture content of 9-12wt%, and a water activity of 0.50-0.65.

[0066] Furthermore, when the fermented pig feed based on palm meal and soybean meal is used as a functional base material in combination with vitamin premix, trace element premix, amino acid raw material and calcium and phosphorus minerals, its addition ratio in the complete feed is 30-70 wt%, the addition ratio of vitamin premix is ​​0.5-2.0 wt%, the addition ratio of trace element premix is ​​0.5-2.0 wt%, the addition ratio of amino acid raw material is 0.5-3.0 wt%, the addition ratio of calcium and phosphorus minerals is 1.0-5.0 wt%, and the balance is conventional energy raw material, protein raw material or other permitted feed components. All nutrients are calculated on a dry basis of the complete feed. The vitamin premix includes one or more vitamins and the effective content is given in IU / kg or mg / kg. The trace element premix includes one or more trace element salts and the effective content is given in terms of elements. The content of vitamins and trace elements in the complete feed is calculated based on the effective content of the premix and the addition ratio.

[0067] As another aspect of this invention, the present invention employs a process design that separately prepares porous palm meal granules I-A1, low-antigen soybean meal binding component I-B1, and composite coated granules I-AB, followed by mixing, conditioning, granulation, cooling, and drying on a dry basis. This process is primarily designed to enhance the adaptability of spray coating, the coating and binding ability, and the stability of the finished product granulation. This method first regulates the state of palm meal and soybean meal through enzymatic hydrolysis and solid-state fermentation, respectively. Then, fluidized bed spraying allows the low-antigen soybean meal binding component I-B1 to form an outer coating layer and / or an agglomerated binding layer on the surface of the porous palm meal granules I-A1, thereby improving the formation quality of the composite coated granules I-AB without compromising the high-porosity digestibility and accessibility. Subsequently, after conditioning to the target moisture content and temperature, granulation, cooling, and drying further stabilize the final product's proportions, particle diameter, and finished product moisture content.

[0068] The primary function of porous palm meal pellets I-A1 is to provide pore volume, pellet skeleton, and coating substrate, focusing on improving high-pore-volume digestibility and maintaining pellet mechanical stability. The primary function of low-antigen soybean meal binder I-B1 is to provide acid-soluble proteins, an outer coating layer, and an agglomeration binder layer, focusing on reducing the influence of glycinin and β-conglycinin, and improving coating binding and forming ability and spray processing compatibility. When low-antigen soybean meal binder I-B1 coats or binds to the surface of porous palm meal pellets I-A1, it simultaneously improves the inter-particle binding state and nutrient contact state, thus ensuring that high-pore-volume digestibility, spray processing compatibility, and pelleting stability are no longer mutually exclusive, but rather coordinated within the same system.

[0069] Beneficial technical effects

[0070] 1. By constructing the low-antigen soybean meal binding component I-B1 as the outer coating layer and / or agglomeration binding layer of the composite coated particles I-AB, and using porous palm meal particles I-A1 as the core layer or particle skeleton, the binding state between particles can be enhanced while maintaining the pore volume characteristics. Therefore, it is more beneficial to improve the mechanical stability of particles and the integrity of subsequent granulation than simply using porous fiber carriers.

[0071] 2. By enzymatically hydrolyzing and solid-state fermenting palm meal and soybean meal respectively, the porous palm meal particles I-A1 have a more suitable pore volume and particle size, and the low-antigen soybean meal binding component I-B1 has a higher acid-soluble protein and reduced glycinin and β-conglycinin. Therefore, it is beneficial to improve the digestibility and accessibility of high-pore-volume feed and the utilization status of pig feed.

[0072] 3. By using fluidized bed spraying to control the solid content of the coating slurry, the inlet air temperature, the material layer temperature, and the spraying time, the low-antigen soybean meal binding component I-B1 can form an outer coating layer and / or an agglomerated binding layer more uniformly. Therefore, it is more beneficial than the ordinary direct mixing method to improve the coating binding and forming ability, the adaptability of spraying processing, and the particle size consistency of the composite coated particles I-AB.

[0073] 4. By simultaneously configuring porous palm meal particles I-A1 (which do not enter the composite coated particles I-AB), low-antigen soybean meal binding component I-B1, and composite coated particles I-AB in the final product, a granular structure in which the dispersed part and the coated part coexist can be formed. Therefore, it is beneficial to maintain the stability of the finished product's moisture content and particle diameter, and also beneficial to expand the application scenarios of functional base materials and granular feeds for pigs. Attached Figure Description

[0074] Figure 1 The following are nitrogen adsorption-desorption isotherms of palm meal coated with substrate in Example 1, Comparative Example 1, and Comparative Example 8.

[0075] Figure 2 The diagram shows the pore size distribution curves of porous palm meal particles I-A1 BJH in Example 1, Comparative Example 1, and Comparative Example 8.

[0076] Figure 3 Two-dimensional correlation diagram of the reduction rate of neutral detergent fiber and pore volume of palm meal coated substrate in Example 1, Comparative Example 1 and Comparative Example 8;

[0077] Figure 4 ELISA standard curve for soybean globulin I-B1, a low-antigen soybean meal binding component;

[0078] Figure 5 ELISA standard curve for low antigen soybean meal binding component I-B1 β-conglycin;

[0079] Figure 6 Figure 1 shows the quantitative results of soybean globulin I-B1, the binding component of low-antigen soybean meal in Examples 1, 3, and 9.

[0080] Figure 7 Figure 1 shows the quantitative results of I-B1 β-conjugated soybean globulin, a binding component of low-antigen soybean meal in Examples 1, 3, and 9.

[0081] Figure 8 The rotational rheological flow curves of the low-antigen soybean meal binding component I-B1 in Examples 1, 4, and 6 are shown.

[0082] Figure 9 This is a magnified view of the neighborhood of the low-antigen soybean meal binding component I-B1 in Examples 1, 4, and 6 (100 s⁻¹).

[0083] Figure 10 The graphs show the thickness distribution of the outer coating layer of the fluidized bed sprayed particles in Examples 1, 5, and 10.

[0084] Figure 11 The thickness distribution curves of the fluidized bed sprayed particle bonding bridges are shown for Examples 1, 5, and 10.

[0085] Figure 12 Box plots and original scatter plots of fluidized bed sprayed particle thickness for Example 1, Comparative Example 5, and Comparative Example 10.

[0086] Figure 13 The graphs show the I-AB differential particle size distribution curves for Example 1, Comparative Example 7, and Comparative Example 10.

[0087] Figure 14 The cumulative particle size distribution curves of I-AB are for Example 1, Comparative Example 7, and Comparative Example 10.

[0088] Figure 15 The graphs show the PDI (Purity Index) decay curves of I-AB particles for Examples 1, 7, and 10.

[0089] Figure 16 The image shows the macroscopic morphology of porous palm meal particles I-A1 prepared in Example 1 of this invention.

[0090] Figure 17 The image shows the macroscopic morphology of the low-antigen soybean meal binding component I-B1 prepared in Example 1 of this invention.

[0091] Figure 18 This is a macroscopic morphology diagram of the final fermented pig feed prepared in Example 1 of the present invention.

[0092] Figure 19 a is a scanning electron microscope image of porous palm meal particles I-A1 prepared in Example 1 of the present invention.

[0093] Figure 19 b is a scanning electron microscope (SEM) image of porous palm meal particles prepared in Example 1 of this invention, at magnification I-A1.

[0094] Figure 19 c is a scanning electron microscope image of the composite coated particles I-AB prepared in Example 1 of this invention.

[0095] Figure 19 d is a high-magnification scanning electron microscope image of the composite coated particles I-AB prepared in Example 1 of this invention. Detailed Implementation

[0096] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0097] Example 1

[0098] This embodiment provides a fermented pig feed based on palm meal and soybean meal. By total dry weight of the final product, it comprises 30 wt% porous palm meal particles I-A1, 17.5 wt% low-antigen soybean meal binder component I-B1, 12 wt% composite coated particles I-AB, and 40.5 wt% corn. Specifically, the 30 wt% porous palm meal particles I-A1 and the 17.5 wt% low-antigen soybean meal binder component I-B1 in this embodiment are the composite coated particles not included in this embodiment of the final product. In the part of particle I-AB, the composite coated particle I-AB of this embodiment is formed by another part of the porous palm meal particle I-A1 of this embodiment and another part of the low antigen soybean meal binding component I-B1 of this embodiment. Moreover, the composite coated particle I-AB of this embodiment is a mononuclear or multinuclear aggregated coated particle with one or more porous palm meal particles I-A1 of this embodiment as the core layer and the low antigen soybean meal binding component I-B1 of this embodiment as the outer coating layer or agglomerated binding layer, or both the outer coating layer and the agglomerated binding layer.

[0099] The porous palm meal granules I-A1 of this embodiment have a pore volume of 0.30 cm³ / g, and the neutral detergent fiber content is reduced by 25% compared to the original palm meal used in preparing the porous palm meal granules I-A1 of this embodiment; the acid-soluble protein in the low-antigen soybean meal binding component I-B1 of this embodiment accounts for 25 wt% of its crude protein, and the total amount of glycinin and β-conglycinin is reduced by 82% compared to the original soybean meal used in preparing the low-antigen soybean meal binding component I-B1 of this embodiment; the particle size of the composite coated granules I-AB of this embodiment after preparation and before being added to the fermented pig feed of this embodiment is 1.5 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 35 μm.

[0100] The porous palm meal granules I-A1 of this embodiment are obtained through the following steps:

[0101] A1. Mix palm meal and deionized water at a mass ratio of 100:38;

[0102] A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1. The amounts of β-mannanase, xylanase, and protease added are 0.15 wt%, 0.10 wt%, and 0.06 wt%, respectively, relative to the mass of palm meal. All amounts added in this embodiment are based on the mass of commercially available enzyme preparations. Enzymatic hydrolysis is performed at 50°C and pH 5.5 for 7 hours.

[0103] A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 5 × 10⁻⁶. 7 CFU / g and 5×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 35°C under aerobic conditions for 36 hours;

[0104] A4. The fermented product obtained in step A3 is dried at 60°C until the moisture content is no more than 12 wt%, pulverized and sieved to 0.6 mm to obtain the porous palm meal particles I-A1 of this embodiment.

[0105] The low-antigen soybean meal binding component I-B1 in this embodiment is prepared through the following steps:

[0106] B1. Mix soybean meal and deionized water at a mass ratio of 100:32;

[0107] B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.18 wt% relative to the mass of soybean meal. In this embodiment, the amount added is based on the mass of a commercial enzyme preparation. Enzymatic hydrolysis is carried out at 48°C and pH 6.3 for 4 hours.

[0108] B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, with the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae being 5 × 10⁻⁶ each. 7 CFU / g and 5×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, solid-state fermentation was carried out at 34℃ under aerobic conditions for 40 hours, and the final pH value of the fermentation was 5.2;

[0109] B4. The fermented product obtained in step B3 is dried at 55°C until the moisture content is no more than 12 wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1 of this embodiment, with a particle size D50 of 175 μm.

[0110] The composite coated particles I-AB in this embodiment are prepared through the following steps:

[0111] C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. In this embodiment, the dry basis mass ratio of porous palm meal particles I-A1 to low-antigen soybean meal binder component I-B1 is 100:50. The amount of deionized water added is adjusted to make the solid content of the coating slurry 60wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 6.0.

[0112] C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 using a fluidized bed spraying method under the conditions of an air inlet temperature of 62°C and a material layer temperature of 40°C, to perform spray coating or spray granulation, and the spraying time is 40 minutes;

[0113] C3. The material obtained in step C2 is dried at 52°C for 2 hours until the moisture content is 10.5 wt%, resulting in the composite coated particles I-AB of this embodiment, with an outer coating layer thickness and an agglomeration and bonding layer characteristic thickness of 35 μm and a particle size of 1.5 mm.

[0114] The fermented pig feed in this embodiment is pelleted feed with a pellet diameter of 4.0 mm and a finished product moisture content of 10.5 wt%.

[0115] The method for preparing fermented pig feed in this embodiment includes the following steps:

[0116] S1. Provides porous palm meal pellets I-A1;

[0117] S2. Provides low-antigen soybean meal binding component I-B1;

[0118] S3. Provides composite coated particles I-AB;

[0119] S4. The porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used in the preparation of composite coated granules I-AB in step S3 are mixed with the composite coated granules I-AB provided in step S3 and corn according to the dry basis to meet the above final product ratio. The mixture is conditioned to a moisture content of 16 wt%, granulated at 70°C, cooled and dried to a finished product moisture content of 10.5 wt% to obtain the fermented pig feed of this embodiment.

[0120] The composite coated particles I-AB provided in step S3 are obtained by fluidized bed spraying, and the conditioning time in step S4 is 40s; in this embodiment, after granulation in step S4, the material temperature is cooled to 32°C.

[0121] The low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment has a particle size D50 of 175 μm.

[0122] Both the porous palm meal granules I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment were obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis used had a viable count of 5 × 10⁻⁶. 10 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a viable count of 5 × 10⁶ cells / g. 9 Commercial dry yeast at CFU / g.

[0123] The mass of palm meal, soybean meal, low antigen soybean meal binding component and porous palm meal particles are all calculated on a dry basis. The actual amount of feed is converted to the corresponding dry basis mass based on the measured moisture content of the raw materials. The total mass of fermented wet material is the total mass of raw materials, deionized water, enzyme preparation, pH adjustment solution and bacterial agent. The initial moisture content of the original palm meal and original soybean meal is not higher than 12 wt%.

[0124] The solid content of the system after mixing palm meal and deionized water is 72.5 wt%, and the solid content of the system after mixing soybean meal and deionized water is 75.8 wt%. The solid content in this embodiment is calculated based on the dry basis weight of palm meal or soybean meal and the weight of deionized water added.

[0125] When mixing palm meal with deionized water and soybean meal with deionized water, mechanical stirring is used until the mixture is homogeneous.

[0126] β-Mannanase, xylanase, and protease were all added directly using commercially available solid enzyme preparations and stirred evenly. The enzyme activities of β-Mannanase, xylanase, and protease were 15000 U / g, 12000 U / g, and 60000 U / g, respectively.

[0127] The amount of enzyme preparation added is recorded uniformly according to both the dry basis weight of the raw material and the actual weight of the enzyme preparation, and the corresponding amount of enzyme activity units added is recorded simultaneously.

[0128] The pH of the enzymatic hydrolysis system was adjusted by adding 2 mol / L hydrochloric acid solution or 2 mol / L sodium hydroxide solution dropwise. The pH was measured every 1 hour during the enzymatic hydrolysis process and the adjustment solution was added to maintain the target pH range.

[0129] pH was measured during solid-state enzymatic hydrolysis or fermentation by preparing a slurry at a mass ratio of 1:5 between the sample and deionized water, and then measuring the pH at 25°C using a calibrated pH meter.

[0130] The enzymatic hydrolysis step is carried out in a closed container, and the water loss in the system during the enzymatic hydrolysis is no more than 8 wt% of the initial total water added.

[0131] The actual amount of commercial microbial agent added is calculated by multiplying the target inoculum amount by the total mass of the fermented wet substrate and then dividing by the number of viable bacteria in the commercial microbial agent.

[0132] After inoculation, the material is spread evenly in an open fermentation pan with a layer thickness of 5cm. Under natural ventilation, the material is turned over every 6 hours.

[0133] The fermentation endpoint of soybean meal was determined by the pH stability range. The fermentation endpoint was defined as the system pH being stable within the range of 4.5-6.0 for 6 hours without decreasing.

[0134] The porous palm meal fermentation material was dried by hot air drying at 60℃ and a hot air flow rate of 1.0m / s. The thickness of a single layer of material was 3cm. After drying, it was crushed and sieved by a hammer mill to collect particles with a particle size of 0.6mm.

[0135] The low-antigen soybean meal fermentation product was dried by hot air drying at 55℃ and a hot air flow rate of 1.0m / s. The thickness of a single layer of material was 3cm. After drying, it was crushed by a hammer mill and sieved to control the particle size D50 of the resulting low-antigen soybean meal binding component to be 175μm.

[0136] The particle size D50 of the low-antigen soybean meal binding component was determined by laser particle size distribution method. Before the determination, the sample was ultrasonically dispersed in deionized water for 3 min.

[0137] Acid-soluble protein was determined by extraction with 10wt% trichloroacetic acid, and crude protein content was determined by Kjeldahl nitrogen determination and converted by multiplying nitrogen content by 6.25. Both acid-soluble protein content and crude protein content were calculated based on the dry basis of the sample. During extraction, 15mL of extraction solution was added for every 1g of dry basis of the sample, and the extraction was carried out at 25℃ for 40min. After centrifugation, the supernatant was collected for determination.

[0138] Neutral detergent fiber content was determined using the VanSoest method. All neutral detergent fiber contents were calculated on a dry basis. The neutral detergent fiber reduction rate was calculated by subtracting the neutral detergent fiber content of porous palm meal particles from the original neutral detergent fiber content of palm meal, dividing by the original neutral detergent fiber content of palm meal, and then multiplying by 100%.

[0139] The total amount of daidzein and β-congaidzein was determined by ELISA. The comparison between the original soybean meal and the binding component of the low-antigen soybean meal was conducted using the same detection method and calibration system. All relevant protein totals were calculated on a dry basis. The reduction rate was calculated by subtracting the total amount of daidzein and β-congaidzein in the binding component of the low-antigen soybean meal from the total amount of daidzein and β-congaidzein in the original soybean meal, dividing by the total amount of daidzein and β-congaidzein in the original soybean meal, and then multiplying by 100%.

[0140] The pore volume of porous palm meal particles was determined by nitrogen adsorption-desorption method. The samples were pretreated under vacuum at 90℃ for 8 hours before measurement. The pore volume was calculated on a dry basis.

[0141] The coating slurry was prepared by adding 67 parts of deionized water to 100 parts by weight of the dry basis of the low antigen soybean meal binding component, and mechanically stirring at 500 rpm for 20 minutes until homogeneous.

[0142] The solid content of the coating slurry was calculated based on the dry weight of the low-antigen soybean meal binder and the weight of added deionized water. The apparent viscosity was 2500 mPa·s. In this embodiment, the apparent viscosity was measured at 25°C and a shear rate of 100 s⁻¹. -1 Determined under the specified conditions.

[0143] The pH of the coating slurry was adjusted to 6.0 using a 2 mol / L hydrochloric acid solution or a 2 mol / L sodium hydroxide solution, and the slurry was continuously stirred during the spraying process to maintain its uniformity.

[0144] The spraying process is carried out using a fluidized bed top spraying method. The spraying rate is 15 mL / min based on the dry basis of the substrate to be coated. The spraying rate is matched and set according to the target dry basis mass ratio of the core layer, the outer coating layer and the agglomerated bonding layer, the solid content of the coating slurry and the spraying time. The atomization pressure is 0.2 MPa, the bed wind speed is 1.2 m / s, the loading amount is 2 kg, and the distance from the spray gun outlet to the bed surface is 18 cm.

[0145] The sprayed material was dried at 52°C for 2 hours until the moisture content was 10.5 wt%, and after cooling, particles with a diameter less than 0.5 mm and greater than 2.5 mm were screened out.

[0146] The thickness of the outer coating layer and the characteristic thickness of the agglomeration and bonding layer of the composite coated particles were measured by observing the cross-section of the particles using a scanning electron microscope. For particles with an outer coating layer, the local thickness of the coating layer was measured. For particles with interparticle bonding bridge structures, the characteristic thickness of the bonding bridge at the interface was measured. Thirty particle cross-sections or bonding bridge locations were randomly measured and the average value was taken.

[0147] The particle size of the composite coated particles was determined by sieving, with the 0.5-2.5 mm sieve size range being used as the qualified particle size. Laser particle size distribution was used as an auxiliary characterization method and expressed as volume distribution D50.

[0148] The coating weight gain rate of the composite coated particles is 50%. The coating weight gain rate is determined by the dry basis weight gain method, which is the dry basis weight of the composite coated particles after spraying and drying minus the dry basis weight of the coated substrate before spraying, then divided by the dry basis weight of the coated substrate before spraying and multiplied by 100%.

[0149] When the dry basis mass ratio of the core layer to the outer coating layer and agglomerated adhesive layer formed by the low-antigen soybean meal binder in the composite coated particles is 100:50, the outer coating layer and agglomerated adhesive layer in this embodiment form a continuous shell, a discontinuous shell, or an interparticle adhesive bridge structure. Furthermore, the core layer, outer coating layer, and agglomerated adhesive layer in the composite coated particles are not included in the porous palm meal particles and low-antigen soybean meal binder that do not enter the composite coated particles.

[0150] The finished product granulation process involves steam conditioning until the material moisture content is 16wt%, followed by ring die granulation. The conditioning temperature is 70℃, the conditioning time is 40s, and the finished particle diameter is 4.0mm.

[0151] The cooling after granulation is countercurrent cooling, with a final cooling temperature of 32℃. The finished product has a moisture content of 10.5wt% and a water activity of 0.58.

[0152] This embodiment is applicable to the diet formulation of nursery pigs and growing-finishing pigs, and is especially suitable for large-scale farms with high requirements for feed stability and processing performance.

[0153] Example 2

[0154] This embodiment provides a fermented pig feed based on palm meal and soybean meal. By total dry weight of the final product, it comprises 34 wt% porous palm meal particles I-A1, 12 wt% low-antigen soybean meal binder component I-B1, 7.5 wt% composite coated particles I-AB, and 46.5 wt% wheat. Specifically, the 34 wt% porous palm meal particles I-A1 and the 12 wt% low-antigen soybean meal binder component I-B1 in this embodiment are composite coated particles not included in this embodiment of the final product. In the I-AB portion, the composite coated particles I-AB of this embodiment are formed from another part of the porous palm meal particles I-A1 of this embodiment and another part of the low-antigen soybean meal binding component I-B1 of this embodiment. The composite coated particles I-AB of this embodiment are mononuclear or multinuclear aggregated coated particles with one or more porous palm meal particles I-A1 of this embodiment as the core layer and the low-antigen soybean meal binding component I-B1 of this embodiment as the outer coating layer or agglomerated binding layer, or both the outer coating layer and the agglomerated binding layer.

[0155] The porous palm meal granules I-A1 of this embodiment have a pore volume of 0.38 cm³ / g, and the neutral detergent fiber content is reduced by 30% compared to the original palm meal used in preparing the porous palm meal granules I-A1 of this embodiment; the acid-soluble protein in the low-antigen soybean meal binding component I-B1 of this embodiment accounts for 19 wt% of its crude protein, and the total amount of glycinin and β-conglycinin is reduced by 75% compared to the original soybean meal used in preparing the low-antigen soybean meal binding component I-B1 of this embodiment; the particle size of the composite coated granules I-AB of this embodiment after preparation and before being added to the fermented pig feed of this embodiment is 1.2 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 22 μm.

[0156] The porous palm meal granules I-A1 of this embodiment are obtained through the following steps:

[0157] A1. Mix palm meal and deionized water at a mass ratio of 100:42;

[0158] A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1. The amounts of β-mannanase, xylanase, and protease added are 0.25 wt%, 0.16 wt%, and 0.08 wt%, respectively, relative to the mass of palm meal. All amounts added in this embodiment are based on the mass of commercially available enzyme preparations. Enzymatic hydrolysis is performed at 52°C and pH 5.0 for 8 hours.

[0159] A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 8 × 10⁻⁶. 7 CFU / g and 6×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 36°C under aerobic conditions for 42 hours;

[0160] A4. The fermented product obtained in step A3 is dried at 62°C until the moisture content is no more than 12 wt%, pulverized and sieved to 0.8 mm to obtain the porous palm meal particles I-A1 of this embodiment.

[0161] The low-antigen soybean meal binding component I-B1 in this embodiment is prepared through the following steps:

[0162] B1. Mix soybean meal and deionized water at a mass ratio of 100:28;

[0163] B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.12 wt% relative to the mass of soybean meal. In this embodiment, the amount added is based on the mass of a commercial enzyme preparation. Enzymatic hydrolysis is carried out at 44°C and pH 6.5 for 3 hours.

[0164] B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 3 × 10⁻⁶ each. 7 CFU / g and 3×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, solid-state fermentation was carried out at 32°C under aerobic conditions for 32 hours, and the final pH value of the fermentation was 5.5;

[0165] B4. The fermented product obtained in step B3 is dried at 53°C until the moisture content is no more than 12 wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1 of this embodiment, with a particle size D50 of 120 μm.

[0166] The composite coated particles I-AB in this embodiment are prepared through the following steps:

[0167] C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. In this embodiment, the dry basis mass ratio of porous palm meal particles I-A1 to low-antigen soybean meal binder component I-B1 is 100:32. The amount of deionized water added is adjusted to make the solid content of the coating slurry 68wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 5.5.

[0168] C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 using a fluidized bed spraying method under conditions of 58°C inlet air temperature and 38°C material layer temperature, to perform spray coating or spray granulation, with a spraying time of 28 minutes;

[0169] C3. The material obtained in step C2 is dried at 48°C for 2.5 hours until the moisture content is 10 wt%, to obtain the composite coated particles I-AB of this embodiment, with an outer coating layer thickness and an agglomeration and bonding layer characteristic thickness of 22 μm and a particle size of 1.2 mm.

[0170] The fermented pig feed in this embodiment is pelleted feed with a pellet diameter of 3.5 mm and a finished product moisture content of 10 wt%.

[0171] The method for preparing fermented pig feed in this embodiment includes the following steps:

[0172] S1. Provides porous palm meal pellets I-A1;

[0173] S2. Provides low-antigen soybean meal binding component I-B1;

[0174] S3. Provides composite coated particles I-AB;

[0175] S4. The porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used to prepare the composite coated granules I-AB in step S3 are mixed with the composite coated granules I-AB provided in step S3 and wheat according to the dry basis to meet the above final product ratio, conditioned to a moisture content of 15wt%, granulated at 68°C, cooled and dried to a finished product moisture content of 10wt%, to obtain the fermented pig feed of this embodiment.

[0176] The composite coated particles I-AB provided in step S3 are obtained by fluidized bed spraying, and the conditioning time in step S4 is 30s; in this embodiment, after granulation in step S4, the material temperature is cooled to 28°C.

[0177] The low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment has a particle size D50 of 120 μm.

[0178] Both the porous palm meal granules I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment were obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis used had a viable count of 8 × 10⁻⁶. 10 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a viable count of 6 × 10⁶ cells / g. 9 Commercial dry yeast at CFU / g.

[0179] The mass of palm meal, soybean meal, low antigen soybean meal binding component and porous palm meal particles are all calculated on a dry basis. The actual amount of feed is converted to the corresponding dry basis mass based on the measured moisture content of the raw materials. The total mass of fermented wet material is the total mass of raw materials, deionized water, enzyme preparation, pH adjustment solution and bacterial agent. The initial moisture content of the original palm meal and original soybean meal is not higher than 12 wt%.

[0180] The solid content of the system after mixing palm meal and deionized water is 70.4 wt%, and the solid content of the system after mixing soybean meal and deionized water is 78.1 wt%. The solid content in this embodiment is calculated based on the dry basis weight of palm meal or soybean meal and the weight of deionized water added.

[0181] When mixing palm meal with deionized water and soybean meal with deionized water, mechanical stirring is used until the mixture is homogeneous.

[0182] β-Mannanase, xylanase, and protease were all added directly using commercially available solid enzyme preparations and stirred evenly. The enzyme activities of β-Mannanase, xylanase, and protease were 18000 U / g, 14000 U / g, and 70000 U / g, respectively.

[0183] The amount of enzyme preparation added is recorded uniformly according to both the dry basis weight of the raw material and the actual weight of the enzyme preparation, and the corresponding amount of enzyme activity units added is recorded simultaneously.

[0184] The pH of the enzymatic hydrolysis system was adjusted by adding 2 mol / L hydrochloric acid solution or 2 mol / L sodium hydroxide solution dropwise. The pH was measured every 1 hour during the enzymatic hydrolysis process and the adjustment solution was added to maintain the target pH range.

[0185] pH was measured during solid-state enzymatic hydrolysis or fermentation by preparing a slurry at a mass ratio of 1:5 between the sample and deionized water, and then measuring the pH at 25°C using a calibrated pH meter.

[0186] The enzymatic hydrolysis step is carried out in a semi-closed container, and the water loss of the system during the enzymatic hydrolysis is no more than 6 wt% of the initial total water added.

[0187] The actual amount of commercial microbial agent added is calculated by multiplying the target inoculum amount by the total mass of the fermented wet substrate and then dividing by the number of viable bacteria in the commercial microbial agent.

[0188] The inoculated material was placed in a solid-state fermenter and continuously forced to ventilate at an aeration rate of 0.5 L / min·kg wet material.

[0189] The fermentation endpoint of soybean meal was determined by the pH stability range. The fermentation endpoint was defined as the system pH being stable within the range of 4.5-6.0 for 5 hours without decreasing.

[0190] The porous palm meal fermentation material was dried by hot air drying at 62℃ and a hot air flow rate of 1.5m / s. The thickness of a single layer of material was 2cm. After drying, it was crushed and sieved using a hammer mill to collect particles with a diameter of 0.8mm.

[0191] The low-antigen soybean meal fermentation product was dried by hot air drying at 53℃ and a hot air flow rate of 0.8m / s. The thickness of a single layer of material was 2cm. After drying, it was pulverized by a needle mill and sieved to control the particle size D50 of the resulting low-antigen soybean meal binding component to be 120μm.

[0192] The particle size D50 of the low-antigen soybean meal binding component was determined by laser particle size distribution method. Before the determination, the sample was ultrasonically dispersed in anhydrous ethanol for 2 min.

[0193] Acid-soluble protein was determined by extraction with 10wt% trichloroacetic acid, and crude protein content was determined by Kjeldahl nitrogen determination and converted by multiplying nitrogen content by 6.25. Both acid-soluble protein content and crude protein content were calculated based on the dry basis of the sample. During extraction, 12mL of extraction solution was added for every 1g of dry basis of the sample, and the extraction was carried out at 22℃ for 30min. After centrifugation, the supernatant was collected for determination.

[0194] Neutral detergent fiber content was determined using the VanSoest method. All neutral detergent fiber contents were calculated on a dry basis. The neutral detergent fiber reduction rate was calculated by subtracting the neutral detergent fiber content of porous palm meal particles from the original neutral detergent fiber content of palm meal, dividing by the original neutral detergent fiber content of palm meal, and then multiplying by 100%.

[0195] The total amount of daidzein and β-congaidzein was determined by SDS-PAGE. The comparison between the original soybean meal and the binding component of the low-antigen soybean meal was conducted using the same detection method and calibration system. All relevant protein totals were calculated on a dry basis. The reduction rate was calculated by subtracting the total amount of daidzein and β-congaidzein in the binding component of the low-antigen soybean meal from the total amount of daidzein and β-congaidzein in the original soybean meal, dividing by the total amount of daidzein and β-congaidzein in the original soybean meal, and then multiplying by 100%.

[0196] The pore volume of porous palm meal particles was determined by nitrogen adsorption-desorption method. The samples were pretreated under vacuum at 95℃ for 6 hours before measurement, and the pore volume was calculated on a dry basis.

[0197] The coating slurry was prepared by adding 47 parts of deionized water to 100 parts by weight of the dry basis of the low antigen soybean meal binding component, and mechanically stirring at 600 rpm for 15 minutes until homogeneous.

[0198] The solid content of the coating slurry was calculated based on the dry weight of the low-antigen soybean meal binder and the weight of added deionized water, with an apparent viscosity of 3800 mPa·s. The apparent viscosity in this embodiment was measured at 25°C and a shear rate of 100 s⁻¹. -1 Determined under the specified conditions.

[0199] The pH of the coating slurry is adjusted to 5.5 using a 2 mol / L hydrochloric acid solution or a 2 mol / L sodium hydroxide solution, and the slurry is continuously stirred during the spraying process to maintain its uniformity.

[0200] The spraying process is carried out using a fluidized bed bottom spraying method. The spraying rate is 10 mL / min based on the dry basis of the substrate to be coated. The spraying rate is matched and set according to the target dry basis mass ratio of the core layer, the outer coating layer and the agglomerated bonding layer, the solid content of the coating slurry and the spraying time. The atomization pressure is 0.15 MPa, the bed wind speed is 0.8 m / s, the loading amount is 3 kg, and the distance from the spray gun outlet to the bed surface is 15 cm.

[0201] The sprayed material was dried at 48°C for 2.5 hours until the moisture content was 10 wt%, and after cooling, particles with a diameter less than 0.5 mm and greater than 2.5 mm were screened out.

[0202] The thickness of the outer coating layer and the characteristic thickness of the agglomeration and bonding layer of the composite coated particles were measured by observing the cross-section of the particles using a scanning electron microscope. For particles with an outer coating layer, the local thickness of the coating layer was measured. For particles with interparticle bonding bridge structures, the characteristic thickness of the bonding bridge at the interface was measured. Twenty-five particle cross-sections or bonding bridge locations were randomly measured and the average value was taken.

[0203] The particle size of the composite coated particles was determined by sieving, with the 0.5-2.5 mm sieve size range being used as the qualified particle size. Laser particle size distribution was used as an auxiliary characterization method and expressed as volume distribution D50.

[0204] The coating weight gain rate of the composite coated particles is 32%. The coating weight gain rate is determined by the dry basis weight gain method, which is the dry basis weight of the composite coated particles after spraying and drying minus the dry basis weight of the coated substrate before spraying, then divided by the dry basis weight of the coated substrate before spraying and multiplied by 100%.

[0205] When the dry basis mass ratio of the core layer to the outer coating layer and agglomerated adhesive layer formed by the low-antigen soybean meal binder in the composite coated particles is 100:32, the outer coating layer and agglomerated adhesive layer in this embodiment form a discontinuous shell or interparticle adhesive bridge structure, and the core layer, outer coating layer and agglomerated adhesive layer in the composite coated particles are not included in the porous palm meal particles and low-antigen soybean meal binder that do not enter the composite coated particles.

[0206] The finished product granulation process involves steam conditioning until the material moisture content is 15wt%, followed by flat die granulation. The conditioning temperature is 68℃, the conditioning time is 30s, and the finished product particle diameter is 3.5mm.

[0207] The cooling after granulation is performed using horizontal flow cooling, with a final cooling temperature of 28℃. The finished product has a moisture content of 10wt% and a water activity of 0.52.

[0208] This embodiment is applicable to the diets of piglets in the later stages and nursery pigs with high requirements for fiber digestibility, and is particularly suitable for formulation systems with wheat as the main energy source.

[0209] Example 3

[0210] This embodiment provides a fermented pig feed based on palm meal and soybean meal. By total dry weight of the final product, it comprises 24 wt% porous palm meal particles I-A1, 19 wt% low-antigen soybean meal binder component I-B1, 14 wt% composite coated particles I-AB, and 43 wt% a mixture of corn and wheat (corn to wheat mass ratio of 3:2). In this embodiment, the 24 wt% porous palm meal particles I-A1 and the 19 wt% low-antigen soybean meal binder component I-B1 are the components of the final product that do not enter the final product. In the example of the composite coated particles I-AB, the composite coated particles I-AB of this embodiment are formed by another part of the porous palm meal particles I-A1 of this embodiment and another part of the low antigen soybean meal binding component I-B1 of this embodiment. The composite coated particles I-AB of this embodiment are mononuclear or multinuclear aggregated coated particles with one or more porous palm meal particles I-A1 of this embodiment as the core layer and the low antigen soybean meal binding component I-B1 of this embodiment as the outer coating layer or agglomerated binding layer, or both the outer coating layer and the agglomerated binding layer.

[0211] The porous palm meal granules I-A1 of this embodiment have a pore volume of 0.22 cm³ / g, and the neutral detergent fiber content is reduced by 18% compared to the original palm meal used in preparing the porous palm meal granules I-A1 of this embodiment; the acid-soluble protein in the low-antigen soybean meal binding component I-B1 of this embodiment accounts for 31 wt% of its crude protein, and the total amount of glycinin and β-conglycinin is reduced by 88% compared to the original soybean meal used in preparing the low-antigen soybean meal binding component I-B1 of this embodiment; the particle size of the composite coated granules I-AB of this embodiment after preparation and before being added to the fermented pig feed of this embodiment is 2.0 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 48 μm.

[0212] The porous palm meal granules I-A1 of this embodiment are obtained through the following steps:

[0213] A1. Mix palm meal and deionized water at a mass ratio of 100:33;

[0214] A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1. The amounts of β-mannanase, xylanase, and protease added are 0.08 wt%, 0.05 wt%, and 0.04 wt%, respectively, relative to the mass of palm meal. All amounts added in this embodiment are based on the mass of commercially available enzyme preparations. Enzymatic hydrolysis is performed at 47°C and pH 6.0 for 5 hours.

[0215] A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 2 × 10⁻⁶. 7 CFU / g and 2×106 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 33°C under aerobic conditions for 30 hours;

[0216] A4. The fermented product obtained in step A3 is dried at 58°C until the moisture content is no more than 12 wt%, pulverized and sieved to 0.5 mm to obtain the porous palm meal particles I-A1 of this embodiment.

[0217] The low-antigen soybean meal binding component I-B1 in this embodiment is prepared through the following steps:

[0218] B1. Mix soybean meal and deionized water at a mass ratio of 100:37;

[0219] B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.25 wt% relative to the mass of soybean meal. In this embodiment, the amount added is based on the mass of a commercial enzyme preparation. Enzymatic hydrolysis is carried out at 52°C and pH 5.8 for 5 hours.

[0220] B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 7 × 10⁻⁶. 7 CFU / g and 8×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, solid-state fermentation was carried out at 36℃ under aerobic conditions for 52 hours, and the final pH value of the fermentation was 4.8;

[0221] B4. The fermented product obtained in step B3 is dried at 58°C until the moisture content is no more than 12 wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1 of this embodiment, with a particle size D50 of 240 μm.

[0222] The composite coated particles I-AB in this embodiment are prepared through the following steps:

[0223] C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. In this embodiment, the dry basis mass ratio of porous palm meal particles I-A1 to low-antigen soybean meal binder component I-B1 is 100:65. The amount of deionized water added is adjusted to make the solid content of the coating slurry 52wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 6.5.

[0224] C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 using a fluidized bed spraying method under the conditions of an inlet air temperature of 66°C and a material layer temperature of 43°C, to perform spray coating or spray granulation, with a spraying time of 52 min;

[0225] C3. The material obtained in step C2 is dried at 56°C for 1.5 hours until the moisture content is 11 wt%, to obtain the composite coated particles I-AB of this embodiment, with an outer coating layer thickness and an agglomeration and bonding layer characteristic thickness of 48 μm and a particle size of 2.0 mm.

[0226] The fermented pig feed in this embodiment is pelleted feed with a pellet diameter of 5.0 mm and a finished product moisture content of 11 wt%.

[0227] The method for preparing fermented pig feed in this embodiment includes the following steps:

[0228] S1. Provides porous palm meal pellets I-A1;

[0229] S2. Provides low-antigen soybean meal binding component I-B1;

[0230] S3. Provides composite coated particles I-AB;

[0231] S4. The portion of the porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used to prepare the composite coated granules I-AB in step S3, are mixed with the composite coated granules I-AB provided in step S3 and the mixture of corn and wheat (corn to wheat mass ratio of 3:2) according to the dry basis to meet the above final product ratio. The mixture is then conditioned to a moisture content of 17 wt%, granulated at 72°C, cooled and dried to a finished product moisture content of 11 wt%, to obtain the fermented pig feed of this embodiment.

[0232] The composite coated particles I-AB provided in step S3 are obtained by fluidized bed spraying, and the conditioning time in step S4 is 52s; in this embodiment, after granulation in step S4, the material temperature is cooled to 36°C.

[0233] The low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment has a particle size D50 of 240 μm.

[0234] Both the porous palm meal granules I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment were obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis used had a viable count of 3.5 × 10⁻⁶. 10 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a viable count of 4 × 10⁶ cells / g. 9 Commercial dry yeast at CFU / g.

[0235] The mass of palm meal, soybean meal, low antigen soybean meal binding component and porous palm meal particles are all calculated on a dry basis. The actual amount of feed is converted to the corresponding dry basis mass based on the measured moisture content of the raw materials. The total mass of fermented wet material is the total mass of raw materials, deionized water, enzyme preparation, pH adjustment solution and bacterial agent. The initial moisture content of the original palm meal and original soybean meal is not higher than 12 wt%.

[0236] The solid content of the system after mixing palm meal and deionized water is 75.2 wt%, and the solid content of the system after mixing soybean meal and deionized water is 73.0 wt%. The solid content in this embodiment is calculated based on the dry basis weight of palm meal or soybean meal and the weight of deionized water added.

[0237] When mixing palm meal with deionized water and soybean meal with deionized water, mechanical stirring is used until the mixture is homogeneous.

[0238] β-Mannanase, xylanase, and protease were all added directly from commercially available solid enzyme preparations and stirred evenly. The enzyme activities of β-Mannanase, xylanase, and protease were 12000 U / g, 11000 U / g, and 65000 U / g, respectively.

[0239] The amount of enzyme preparation added is recorded uniformly according to both the dry basis weight of the raw material and the actual weight of the enzyme preparation, and the corresponding amount of enzyme activity units added is recorded simultaneously.

[0240] The pH of the enzymatic hydrolysis system was adjusted by adding 2 mol / L hydrochloric acid solution or 2 mol / L sodium hydroxide solution dropwise. The pH was measured every 1.5 hours during the enzymatic hydrolysis process and the adjustment solution was added to maintain the target pH range.

[0241] pH was measured during solid-state enzymatic hydrolysis or fermentation by preparing a slurry at a mass ratio of 1:5 between the sample and deionized water, and then measuring the pH at 25°C using a calibrated pH meter.

[0242] The enzymatic hydrolysis step is carried out in a closed container, and the water loss in the system during the enzymatic hydrolysis is no more than 5 wt% of the initial total water added.

[0243] The actual amount of commercial microbial agent added is calculated by multiplying the target inoculum amount by the total mass of the fermented wet substrate and then dividing by the number of viable bacteria in the commercial microbial agent.

[0244] After inoculation, the material is spread evenly in a perforated tray with a layer thickness of 4cm, and turned over every 5 hours under natural ventilation.

[0245] The fermentation endpoint of soybean meal was determined by the pH stability range. The fermentation endpoint was defined as the system pH being stable within the range of 4.5-6.0 for 7 hours without decreasing.

[0246] The porous palm meal fermentation material was dried by hot air drying at 58℃ and a hot air flow rate of 0.8m / s. The thickness of a single layer of material was 4cm. After drying, it was crushed and sieved by a hammer mill to collect particles with a diameter of 0.5mm.

[0247] The low-antigen soybean meal fermentation product was dried by hot air drying at 58℃ and a hot air flow rate of 1.5m / s. The thickness of a single layer of material was 2.5cm. After drying, it was crushed by a hammer mill and sieved to control the particle size D50 of the resulting low-antigen soybean meal binding component to be 240μm.

[0248] The particle size D50 of the low-antigen soybean meal binding component was determined by laser particle size distribution method. Before the determination, the sample was ultrasonically dispersed in deionized water for 4 min.

[0249] Acid-soluble protein was determined by extraction with 10wt% trichloroacetic acid, and crude protein content was determined by Kjeldahl nitrogen determination and converted by multiplying nitrogen content by 6.25. Both acid-soluble protein content and crude protein content were calculated based on the dry basis of the sample. During extraction, 18mL of extraction solution was added per 1g of dry basis of the sample, and the extraction was carried out at 28℃ for 50min. After centrifugation, the supernatant was collected for determination.

[0250] Neutral detergent fiber content was determined using the VanSoest method. All neutral detergent fiber contents were calculated on a dry basis. The neutral detergent fiber reduction rate was calculated by subtracting the neutral detergent fiber content of porous palm meal particles from the original neutral detergent fiber content of palm meal, dividing by the original neutral detergent fiber content of palm meal, and then multiplying by 100%.

[0251] The total amount of daidzein and β-congaidzein was determined by ELISA. The comparison between the original soybean meal and the binding component of the low-antigen soybean meal was conducted using the same detection method and calibration system. All relevant protein totals were calculated on a dry basis. The reduction rate was calculated by subtracting the total amount of daidzein and β-congaidzein in the binding component of the low-antigen soybean meal from the total amount of daidzein and β-congaidzein in the original soybean meal, dividing by the total amount of daidzein and β-congaidzein in the original soybean meal, and then multiplying by 100%.

[0252] The pore volume of porous palm meal particles was determined by nitrogen adsorption-desorption method. The samples were pretreated under vacuum at 85℃ for 10 h before measurement. The pore volume was calculated on a dry basis.

[0253] The coating slurry was prepared by adding 92 parts of deionized water to 100 parts by weight of the dry basis of the low antigen soybean meal binding component, and mechanically stirring at 400 rpm for 25 minutes until homogeneous.

[0254] The solid content of the coating slurry was calculated based on the dry weight of the low-antigen soybean meal binder and the weight of added deionized water. The apparent viscosity was 1200 mPa·s. In this embodiment, the apparent viscosity was measured at 25°C and a shear rate of 100 s⁻¹. -1Determined under the specified conditions.

[0255] The pH of the coating slurry is adjusted to 6.5 using a 2 mol / L hydrochloric acid solution or a 2 mol / L sodium hydroxide solution, and the slurry is continuously stirred during the spraying process to maintain its uniformity.

[0256] The spraying process is carried out using a fluidized bed top spraying method. The spraying rate is 25 mL / min based on the dry basis of the substrate to be coated. The spraying rate is matched and set according to the target dry basis mass ratio of the core layer, the outer coating layer and the agglomerated bonding layer, the solid content of the coating slurry and the spraying time. The atomization pressure is 0.25 MPa, the bed wind speed is 1.8 m / s, the loading amount is 4 kg, and the distance from the spray gun outlet to the bed surface is 22 cm.

[0257] The sprayed material was dried at 56°C for 1.5 hours until the moisture content was 11 wt%, and after cooling, particles with a diameter less than 0.5 mm and greater than 2.5 mm were screened out.

[0258] The thickness of the outer coating layer and the characteristic thickness of the agglomeration and bonding layer of the composite coated particles were measured by observing the cross-section of the particles using a scanning electron microscope. For particles with an outer coating layer, the local thickness of the coating layer was measured. For particles with interparticle bonding bridge structures, the characteristic thickness of the bonding bridge at the interface was measured. Forty particle cross-sections or bonding bridge locations were randomly measured and the average value was taken.

[0259] The particle size of the composite coated particles was determined by sieving, with the 0.5-2.5 mm sieve size range being used as the qualified particle size. Laser particle size distribution was used as an auxiliary characterization method and expressed as volume distribution D50.

[0260] The coating weight gain rate of the composite coated particles is 65%. The coating weight gain rate is determined by the dry basis weight gain method, which is the dry basis weight of the composite coated particles after spraying and drying minus the dry basis weight of the coated substrate before spraying, then divided by the dry basis weight of the coated substrate before spraying and multiplied by 100%.

[0261] When the dry basis mass ratio of the core layer to the outer coating layer and agglomerated adhesive layer formed by the low-antigen soybean meal binder in the composite coated particles is 100:65, the outer coating layer and agglomerated adhesive layer in this embodiment form a continuous shell and interparticle adhesive bridge structure. Furthermore, the core layer, outer coating layer, and agglomerated adhesive layer in the composite coated particles are not included in the porous palm meal particles and low-antigen soybean meal binder that do not enter the composite coated particles.

[0262] When using a mixture of corn and wheat, the mass ratio of corn to wheat is 3:2.

[0263] The finished product granulation process involves steam conditioning until the material moisture content is 17wt%, followed by ring die granulation. The conditioning temperature is 72℃, the conditioning time is 52s, and the finished product particle diameter is 5.0mm.

[0264] The granulation cooling process uses countercurrent cooling, with a final cooling temperature of 36℃. The finished product has a moisture content of 11wt% and a water activity of 0.62.

[0265] This embodiment is applicable to diets for early-weaned piglets and sensitive pigs with strict requirements for antigen protein control, and is particularly suitable for feed products that require enhanced pellet binding and durability.

[0266] Example 4

[0267] This embodiment provides a fermented pig feed based on palm meal and soybean meal. Based on the total dry weight of the final product, it includes 22 wt% porous palm meal particles I-A1, 14 wt% low-antigen soybean meal binding component I-B1, 17 wt% composite coated particles I-AB, and 47 wt% wheat. The 22 wt% porous palm meal particles I-A1 and 14 wt% low-antigen soybean meal binding component I-B1 in this embodiment are portions of the final product that do not enter into the composite coated particles I-AB of this embodiment. The composite coated particles I-AB of this embodiment are formed from another portion of the porous palm meal particles I-A1 and another portion of the low-antigen soybean meal binding component I-B1 of this embodiment. Furthermore, the composite coated particles I-AB of this embodiment are mononuclear or multinuclear aggregated coated particles with one or more porous palm meal particles I-A1 as the core layer and the low-antigen soybean meal binding component I-B1 forming the outer coating layer or agglomerated binding layer, or simultaneously forming both an outer coating layer and an agglomerated binding layer.

[0268] The porous palm meal granules I-A1 of this embodiment have a pore volume of 0.27 cm³ / g, and the neutral detergent fiber content is reduced by 22% compared to the original palm meal used in preparing the porous palm meal granules I-A1 of this embodiment; the acid-soluble protein in the low-antigen soybean meal binding component I-B1 of this embodiment accounts for 33 wt% of its crude protein, and the total amount of daidzein and β-congaidzein is reduced by 91% compared to the original soybean meal used in preparing the low-antigen soybean meal binding component I-B1 of this embodiment; the particle size of the composite coated granules I-AB of this embodiment after preparation and before being added to the fermented pig feed of this embodiment is 2.3 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 55 μm.

[0269] The porous palm meal granules I-A1 of this embodiment are obtained through the following steps:

[0270] A1. Mix palm meal with deionized water at a mass ratio of 100:31;

[0271] A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1. The amounts of β-mannanase, xylanase, and protease added are 0.27 wt%, 0.18 wt%, and 0.03 wt%, respectively, relative to the mass of palm meal. All amounts added in this embodiment are based on the mass of commercially available enzyme preparations. Enzymatic hydrolysis is performed at 46°C and pH 6.3 for 9 hours.

[0272] A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 1.5 × 10⁻⁶ respectively. 7 CFU / g and 8×10 5 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 32.5℃ under aerobic conditions for 44 hours;

[0273] A4. The fermented product obtained in step A3 is dried at 64°C until the moisture content is no more than 12 wt%, pulverized and sieved to 0.35 mm to obtain the porous palm meal particles I-A1 of this embodiment.

[0274] The low-antigen soybean meal binding component I-B1 in this embodiment is prepared through the following steps:

[0275] B1. Mix soybean meal and deionized water at a mass ratio of 100:39;

[0276] B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.28 wt% relative to the mass of soybean meal. In this embodiment, the amount added is based on the mass of a commercially available enzyme preparation. Enzymatic hydrolysis is carried out at 54°C and pH 6.8 for 5.5 h.

[0277] B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 9 × 10⁻⁶. 7 CFU / g and 9×10 6 CFU / g, the inoculum amount in this example is based on the total mass of the fermented wet material, solid-state fermentation was carried out at 37°C under aerobic conditions for 56 hours, and the final pH value of the fermentation was 4.6;

[0278] B4. The fermented product obtained in step B3 is dried at 59°C until the moisture content is no more than 12 wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1 of this embodiment, with a particle size D50 of 280 μm.

[0279] The composite coated particles I-AB in this embodiment are prepared through the following steps:

[0280] C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. In this embodiment, the dry basis mass ratio of porous palm meal particles I-A1 to low-antigen soybean meal binder component I-B1 is 100:75. The amount of deionized water added is adjusted to make the solid content of the coating slurry 48wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 5.2.

[0281] C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 using a fluidized bed spraying method under conditions of 69°C inlet air temperature and 36°C material layer temperature, to perform spray coating or spray granulation, with a spraying time of 56 min;

[0282] C3. The material obtained in step C2 is dried at 59°C for 2.8 hours until the moisture content is 9.5 wt%, to obtain the composite coated particles I-AB of this embodiment, with an outer coating layer thickness and an agglomeration and bonding layer characteristic thickness of 55 μm and a particle size of 2.3 mm.

[0283] The fermented pig feed in this embodiment is pelleted feed with a pellet diameter of 5.5 mm and a finished product moisture content of 11.5 wt%.

[0284] The method for preparing fermented pig feed in this embodiment includes the following steps:

[0285] S1. Provides porous palm meal pellets I-A1;

[0286] S2. Provides low-antigen soybean meal binding component I-B1;

[0287] S3. Provides composite coated particles I-AB;

[0288] S4. The porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used in the preparation of composite coated granules I-AB in step S3 are mixed with the composite coated granules I-AB provided in step S3 and wheat according to the dry basis to meet the above final product ratio, and conditioned to a moisture content of 17.5 wt%. Granulation is carried out at 74°C, and the mixture is cooled and dried to a finished product moisture content of 11.5 wt% to obtain the fermented pig feed of this embodiment.

[0289] The composite coated particles I-AB provided in step S3 are obtained by fluidized bed spraying, and the conditioning time in step S4 is 56s; in this embodiment, after granulation in step S4, the material temperature is cooled to 38°C.

[0290] The low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment has a particle size D50 of 280 μm.

[0291] Both the porous palm meal granules I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 of this embodiment were obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis used had a viable count of 7.5 × 10⁻⁶. 10 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a viable count of 8 × 10⁶ cells / g. 9 Commercial dry yeast at CFU / g.

[0292] The mass of palm meal, soybean meal, low antigen soybean meal binding component and porous palm meal particles are all calculated on a dry basis. The actual amount of feed is converted to the corresponding dry basis mass based on the measured moisture content of the raw materials. The total mass of fermented wet material is the total mass of raw materials, deionized water, enzyme preparation, pH adjustment solution and bacterial agent. The initial moisture content of the original palm meal and original soybean meal is not higher than 12 wt%.

[0293] The solid content of the system after mixing palm meal and deionized water is 76.3 wt%, and the solid content of the system after mixing soybean meal and deionized water is 71.9 wt%. The solid content in this embodiment is calculated based on the dry basis weight of palm meal or soybean meal and the weight of deionized water added.

[0294] When mixing palm meal with deionized water and soybean meal with deionized water, mechanical stirring is used until the mixture is homogeneous.

[0295] β-Mannanase, xylanase, and protease were all added directly using commercially available solid enzyme preparations and stirred evenly. The enzyme activities of β-Mannanase, xylanase, and protease were 20,000 U / g, 16,000 U / g, and 55,000 U / g, respectively.

[0296] The amount of enzyme preparation added is recorded uniformly according to both the dry basis weight of the raw material and the actual weight of the enzyme preparation, and the corresponding amount of enzyme activity units added is recorded simultaneously.

[0297] The pH of the enzymatic hydrolysis system was adjusted by adding 2 mol / L hydrochloric acid solution or 2 mol / L sodium hydroxide solution dropwise. The pH was measured every 0.5 h during the enzymatic hydrolysis process and the adjustment solution was added to maintain the target pH range.

[0298] pH was measured during solid-state enzymatic hydrolysis or fermentation by preparing a slurry at a mass ratio of 1:5 between the sample and deionized water, and then measuring the pH at 25°C using a calibrated pH meter.

[0299] The enzymatic hydrolysis step is carried out in a closed container, and the water loss of the system during the enzymatic hydrolysis is no more than 10 wt% of the initial total water added.

[0300] The actual amount of commercial microbial agent added is calculated by multiplying the target inoculum amount by the total mass of the fermented wet substrate and then dividing by the number of viable bacteria in the commercial microbial agent.

[0301] The inoculated material was placed in a solid-state fermenter and intermittent forced ventilation was carried out at an aeration rate of 0.8 L / min·kg wet material.

[0302] The fermentation endpoint of soybean meal was determined by the pH stability range. The fermentation endpoint was defined as the system pH being stable within the range of 4.5-6.0 for 4 hours without decreasing.

[0303] The porous palm meal fermentation material was dried by hot air drying at 64℃ and a hot air flow rate of 1.8m / s. The thickness of a single layer of material was 1.5cm. After drying, it was crushed and sieved by a hammer mill to collect particles with a diameter of 0.35mm.

[0304] The low-antigen soybean meal fermentation product was dried by hot air drying at 59℃ and a hot air flow rate of 1.8m / s. The thickness of a single layer of material was 1.5cm. After drying, it was crushed by a hammer mill and sieved to control the particle size D50 of the resulting low-antigen soybean meal binding component to be 280μm.

[0305] The particle size D50 of the low-antigen soybean meal binding component was determined by laser particle size distribution method. Before the determination, the sample was ultrasonically dispersed in deionized water for 5 min.

[0306] Acid-soluble protein was determined by extraction with 10wt% trichloroacetic acid, and crude protein content was determined by Kjeldahl nitrogen determination and converted by multiplying nitrogen content by 6.25. Both acid-soluble protein content and crude protein content were calculated based on the dry basis of the sample. During extraction, 20mL of extraction solution was added per 1g of dry basis of the sample, and the extraction was carried out at 30℃ for 60min. After centrifugation, the supernatant was collected for determination.

[0307] Neutral detergent fiber content was determined using the VanSoest method. All neutral detergent fiber contents were calculated on a dry basis. The neutral detergent fiber reduction rate was calculated by subtracting the neutral detergent fiber content of porous palm meal particles from the original neutral detergent fiber content of palm meal, dividing by the original neutral detergent fiber content of palm meal, and then multiplying by 100%.

[0308] The total amount of daidzein and β-congaidzein was determined by ELISA. The comparison between the original soybean meal and the binding component of the low-antigen soybean meal was conducted using the same detection method and calibration system. All relevant protein totals were calculated on a dry basis. The reduction rate was calculated by subtracting the total amount of daidzein and β-congaidzein in the binding component of the low-antigen soybean meal from the total amount of daidzein and β-congaidzein in the original soybean meal, dividing by the total amount of daidzein and β-congaidzein in the original soybean meal, and then multiplying by 100%.

[0309] The pore volume of porous palm meal particles was determined by nitrogen adsorption-desorption method. The samples were pretreated under vacuum at 100℃ for 5 hours before measurement, and the pore volume was calculated on a dry basis.

[0310] The coating slurry was prepared by adding 100 parts by weight of dry weight of low antigen soybean meal binding component to 108 parts by weight of deionized water, and mechanically stirring at 700 rpm for 12 minutes until homogeneous.

[0311] The solid content of the coating slurry was calculated based on the dry weight of the low-antigen soybean meal binder and the weight of added deionized water. The apparent viscosity was 800 mPa·s. In this embodiment, the apparent viscosity was measured at 25°C and a shear rate of 100 s⁻¹. -1 Determined under the specified conditions.

[0312] The pH of the coating slurry was adjusted to 5.2 using a 2 mol / L hydrochloric acid solution or a 2 mol / L sodium hydroxide solution, and the slurry was continuously stirred during the spraying process to maintain its uniformity.

[0313] The spraying process was carried out using a fluidized bed top spraying method. The spraying rate was 28 mL / min based on the dry basis of the substrate to be coated. The spraying rate was matched and set according to the target dry basis mass ratio of the core layer, the outer coating layer and the agglomerated bonding layer, the solid content of the coating slurry and the spraying time. The atomization pressure was 0.28 MPa, the bed wind speed was 1.9 m / s, the loading amount was 4.5 kg and the distance from the spray gun outlet to the bed surface was 12 cm.

[0314] The sprayed material was dried at 59°C for 2.8 hours until the moisture content was 9.5 wt%, and after cooling, particles with a diameter of less than 0.5 mm and greater than 2.5 mm were screened out.

[0315] The thickness of the outer coating layer and the characteristic thickness of the agglomeration and bonding layer of the composite coated particles were measured by observing the cross-section of the particles using a scanning electron microscope. For particles with an outer coating layer, the local thickness of the coating layer was measured. For particles with interparticle bonding bridge structures, the characteristic thickness of the bonding bridge at the interface was measured. Fifty particle cross-sections or bonding bridge locations were randomly measured and the average value was taken.

[0316] The particle size of the composite coated particles was determined by sieving, with the 0.5-2.5 mm sieve size range being used as the qualified particle size. Laser particle size distribution was used as an auxiliary characterization method and expressed as volume distribution D50.

[0317] The coating weight gain rate of the composite coated particles is 75%. The coating weight gain rate is determined by the dry basis weight gain method, which is the dry basis weight of the composite coated particles after spraying and drying minus the dry basis weight of the coated substrate before spraying, then divided by the dry basis weight of the coated substrate before spraying and multiplied by 100%.

[0318] When the dry basis mass ratio of the core layer to the outer coating layer and agglomerated adhesive layer formed by the low-antigen soybean meal binder in the composite coated particles is 100:75, the outer coating layer and agglomerated adhesive layer in this embodiment form a composite structure of continuous shell and discontinuous shell. Furthermore, the core layer, outer coating layer and agglomerated adhesive layer in the composite coated particles are not included in the porous palm meal particles and low-antigen soybean meal binder that do not enter the composite coated particles.

[0319] The finished product granulation process involves steam conditioning until the material moisture content is 17.5 wt%, followed by ring die granulation. The conditioning temperature is 74 ℃, the conditioning time is 56 s, and the finished particle diameter is 5.5 mm.

[0320] The granulation cooling process uses countercurrent cooling, with a final cooling temperature of 38℃. The finished product has a moisture content of 11.5 wt% and a water activity of 0.64.

[0321] This embodiment uses a low ratio of porous palm meal particles and a medium ratio of low-antigen soybean meal binding components, which is suitable for pigs at various growth stages with high requirements for protein digestibility and antigen control. It is especially suitable for market environments with high requirements for the production and storage of large-particle feed.

[0322] Comparative Example 1: Basically the same as Example 1, except that in step A2, the amount of β-mannanase added is 0.01 wt%, the amount of xylanase added is still 0.10 wt%, the amount of protease added is still 0.06 wt%, and other conditions remain unchanged.

[0323] Comparative Example 2: It is basically the same as Example 1, except that the solid-state fermentation time in step A3 is 18h, and the inoculation amount of Bacillus subtilis and Saccharomyces cerevisiae, fermentation temperature and other conditions remain unchanged.

[0324] Comparative Example 3: It is basically the same as Example 1, except that the amount of protease added in step B2 is 0.02wt%, the enzymatic hydrolysis temperature, pH value and enzymatic hydrolysis time remain unchanged, and other conditions remain unchanged.

[0325] Comparative Example 4: It is basically the same as Example 1, except that the low-antigen soybean meal binding component I-B1 obtained in step B4 is further pulverized and classified by airflow to control the particle size D50 to 25 μm, and then used in step C1 to prepare the coating slurry, with other conditions remaining unchanged.

[0326] Comparative Example 5: It is basically the same as Example 1, except that in step C1, the dry basis mass ratio of porous palm meal particles I-A1 to low antigen soybean meal binding component I-B1 is 100:10, the amount of deionized water added is adjusted so that the solid content of the coating slurry is still 60wt%, and other conditions remain unchanged.

[0327] Comparative Example 6: It is basically the same as Example 1, except that the amount of deionized water added in step C1 is adjusted to the solid content of the coating slurry is 80wt%, the dry basis mass ratio of porous palm meal particles I-A1 to low antigen soybean meal binding component I-B1 is still 100:50, and other conditions remain unchanged.

[0328] Comparative Example 7: It is basically the same as Example 1, except that the spraying time in step C2 is 10 min, while the air inlet temperature, material layer temperature, coating slurry composition and subsequent drying conditions remain unchanged.

[0329] Comparative Example 8: Essentially the same as Example 1, except that steps A1-A4 are omitted. Instead, the raw palm meal is dried at 60°C until the moisture content is no more than 12 wt%, pulverized, and sieved to 0.6 mm, serving as the coating substrate in step C1. The remaining conditions for steps C1-C3 and step S4 remain unchanged. This comparative example is used to verify the synergistic effect of porous palm meal particles I-A1 and low-antigen soybean meal binding component I-B1 in composite coated particles I-AB.

[0330] Comparative Example 9: Essentially the same as Example 1, except that steps B1-B4 are omitted. Instead, the raw soybean meal is dried at 55°C until the moisture content is no higher than 12 wt%, pulverized, and sieved to control the particle size D50 at 175 μm. This pulverized soybean meal is used as the soybean meal component for preparing the coated slurry in step C1. The remaining conditions for steps C1-C3 and step S4 remain unchanged. This comparative example is used to verify the synergistic effect of the low-antigen soybean meal binding component I-B1 and the porous palm meal particles I-A1 in the composite coated particles I-AB.

[0331] Comparative Example 10: This example is essentially the same as Example 1, except that in step S3, instead of using fluidized bed spraying to prepare the composite coated particles I-AB, porous palm meal particles I-A1 and low-antigen soybean meal binder I-B1 are first dry-mixed for 2 minutes, then sprayed into a slurry adjusted to a solid content of 60 wt% and a pH of 6.0. The mixture is then wet-granulated at 20 rpm for 10 minutes in a rotary drum granulator, followed by drying at 52°C for 2 hours, with other conditions remaining unchanged. This comparative example is used to verify the synergistic effect of porous palm meal particles I-A1, low-antigen soybean meal binder I-B1, and the fluidized bed spraying interface construction method.

[0332] Performance testing:

[0333] Samples were taken on a dry basis and pretreated in vacuum at 90℃ for 8 hours. The nitrogen adsorption-desorption isotherm was measured at 77K. The BJH pore size distribution and cumulative pore volume were calculated by adsorption amount and relative pressure P / P0 to verify whether the pore volume and pore size distribution were within the target window and supported digestion accessibility. The isotherm and pore size distribution data were exported after three parallel measurements. The results are expressed as mean ± standard deviation.

[0334] Neutral detergent fiber content was determined simultaneously in both raw palm meal and treated samples. A uniform dry basis conversion, the same batch of reagents, the same digestion system, and the same blank correction were used. The fiber level was reflected by the weight of the neutral detergent fiber residue. The reduction rate of the treated sample relative to the raw palm meal was calculated. After three parallel determinations, the original mass, residue mass, and reduction rate data were output and reported as mean ± standard deviation.

[0335] The crude protein content of the samples was determined by the Kjeldahl method. The crude protein was obtained by multiplying the total nitrogen by a conversion factor of 6.25. The nitrogen content in the supernatant extracted with 10 wt% trichloroacetic acid was determined by the same method and converted to acid-soluble protein. The raw soybean meal and the treated samples were tested simultaneously using the same digestion, distillation and conversion factor. After three parallel determinations, the total nitrogen, supernatant nitrogen, crude protein and acid-soluble protein ratio data were output.

[0336] The raw soybean meal and the treated samples were compared quantitatively using ELISA with the same antibody system for glycine globulin and β-conglycine globulin. The dry basis conversion, extraction system and plate detection were unified. A standard curve (R²≥0.995) was set, and three parallel determinations were performed using quality control samples. The protein concentration was calculated by the OD450 value and the reduction rate of the treated samples relative to the raw soybean meal was compared. The OD450, concentration and reduction rate data were exported.

[0337] After the coating slurry was prepared, it was allowed to stand to remove bubbles. The apparent viscosity was measured for 60 seconds at a shear rate of 100 s⁻¹ using a rotational rheometer at 25°C. The atomization and film formation stability were evaluated to verify the compatibility window of the spraying process. Before the test, the slurry was continuously stirred to ensure uniformity. After three parallel measurements, the shear rate-viscosity data were exported and the mean ± standard deviation was reported.

[0338] Weigh 100g of sample and sieve for 10min. Calculate the mass percentage of qualified particles in the 0.5-2.5mm range. If necessary, take another sample, disperse it, and use laser diffraction to determine the particle size distribution parameters D10, D50, and D90 to verify the particle size distribution range of the composite coated particles. After three parallel determinations, export the sieving results and particle size distribution data.

[0339] Finished fermented pig feed pellets were subjected to a rotary drum durability test with a uniform sample loading (i.e., using the conventional rotary drum method in feed pellet durability testing). Moisture content was measured simultaneously before and after the test. The pellet durability index (PDI) was calculated by statistically analyzing the retention rate of intact pellets and the mass of fine powder after rotation, which verified the mechanical stability and post-processing retention of the pellets. After three parallel tests, the data of retained mass, fine powder mass, moisture content, and PDI were output.

[0340] Figure 1The figures are nitrogen adsorption-desorption isotherms of porous palm meal particles I-A1 in Examples 1, 1, and 8. The pore structure of the particles was characterized by nitrogen adsorption-desorption. Example 1 showed a higher adsorption capacity and a more obvious hysteresis characteristic, indicating that the synergistic treatment of enzymatic hydrolysis and solid-state fermentation is beneficial to the formation of a more developed mesoporous structure.

[0341] Figure 2 The figures I-A1 show the BJH pore size distribution curves of porous palm meal particles in Example 1, Comparative Example 1, and Comparative Example 8. The pore size distribution was characterized using the BJH pore size analysis method. Example 1 has a more concentrated and higher distribution peak in the mesopore region, indicating that its pore structure is more conducive to the subsequent loading of binder components and interface construction.

[0342] Figure 3 The two-dimensional correlation diagram of the aNDF reduction rate and pore volume of porous palm meal particles I-A1 in Examples 1, 1, and 8 is shown. The correlation analysis method of fiber degradation index and pore structure parameter is used for characterization. The results show that the increase in pore volume and the decrease in aNDF have the same trend, indicating that there is a stable synergistic relationship between fiber degradation and porous structure formation.

[0343] Figure 4 The image shows the ELISA standard curve for soybean globulin I-B1, a binding component of low-antigen soybean meal. The ELISA method was used to establish the quantitative relationship between the concentration of soybean globulin standard and absorbance. The curve fit was good, indicating that this method can be used for the accurate determination of soybean globulin in subsequent samples.

[0344] Figure 5 The standard curve for ELISA of low-antigen soybean meal binding component I-B1 β-conglycin is shown. The quantitative relationship between the concentration and absorbance of β-conglycin standard was established using the ELISA method. The standard response was stable, indicating that this method can support the reliable quantification of β-conglycin in subsequent samples.

[0345] Figure 6 The graph shows the quantitative results of soybean globulin I-B1, the binding component of low-antigen soybean meal in Examples 1, 3, and 9. The residual level of soybean globulin in different samples was characterized by ELISA. The content in Example 1 was significantly lower, indicating that the treatment pathway can effectively reduce the level of the main antigen protein.

[0346] Figure 7 The graph shows the quantitative results of β-conglycinin I-B1, a binding component of low-antigen soybean meal in Examples 1, 3, and 9. The residual level of β-conglycinin in different samples was characterized by ELISA. Example 1 also showed a low residual amount, indicating that low-antigen modification has a synergistic reduction effect on both major antigenic proteins.

[0347] Figure 8 The rotational rheological flow curves of the low-antigen soybean meal binding component I-B1 in Examples 1, 4, and 6 are shown. The rotational rheology method was used to characterize the viscosity change behavior of the slurry at different shear rates. Example 1 showed more suitable shear thinning characteristics in the full shear range, indicating that it is more suitable for conveying and atomizing during the spraying process.

[0348] Figure 9 For Example 1, Comparative Example 4, and Comparative Example 6, the low-antigen soybean meal binding component I-B1 was used in 100 s. -1 The magnified view of the neighborhood shows that the key shear window of the spraying was analyzed locally using the rotational rheology method. In Example 1, the viscosity was more moderate in the target shear range, indicating that its process adaptability was better and it was conducive to forming a stable and uniform coating layer.

[0349] Figure 10 The graphs show the thickness distribution of the outer coating layer of the fluidized bed sprayed particles in Examples 1, 5, and 10. The thickness of the outer coating layer was characterized by cross-sectional image measurement and statistical distribution analysis. The distribution of the outer coating layer in Example 1 is more concentrated and the thickness is more uniform, indicating that its spraying deposition process is more stable and can form a continuous coating interface.

[0350] Figure 11 The thickness distribution curves of the bonding bridges between particles in fluidized bed spraying are shown for Examples 1, 5, and 10. The bonding bridge structure between particles was characterized by cross-sectional image measurement and statistical distribution analysis. The bonding bridge distribution in Example 1 is more complete and uniform, indicating that it is more conducive to effective connection and structural maintenance between particles.

[0351] Figure 12 Box plots and original scatter plots of fluidized bed sprayed particle thickness for Example 1, Comparative Example 5, and Comparative Example 10 were used to comprehensively compare the thickness of the outer coating layer and the bonding bridge using statistical distribution analysis. Example 1 showed smaller dispersion and a more stable median level, indicating that the interface construction had good repeatability and consistency.

[0352] Figure 13 The I-AB differential particle size distribution curves for Example 1, Comparative Example 7, and Comparative Example 10 are shown. The particle size distribution analysis method is used to characterize the changes in the position of the main peak of the particles and the proportion of fine powder. The main peak of Example 1 is more concentrated and the content of fine powder is lower, indicating that its particle size control effect is more stable.

[0353] Figure 14 The cumulative particle size distribution curves of Example 1, Comparative Example 7, and Comparative Example 10 are shown in I-AB. The cumulative particle size analysis method is used to characterize the distribution characteristics of particles within the target particle size range. The cumulative change of Example 1 within the suitable particle size range is more stable, indicating that it is more conducive to obtaining uniform and controllable finished particle size.

[0354] Figure 15The graphs show the PDI decay curves of the I-AB particle durability index for Examples 1, 7, and 10. The particle durability test method was used to characterize the particle integrity retention ability under cyclic action. Example 1 showed a smaller PDI decrease and less fine powder generation, indicating that a stable spray interface and bonding structure can effectively improve particle mechanical retention.

[0355] Figure 16 The macroscopic morphology of porous palm meal particles I-A1 prepared in Example 1 of this invention is shown. The sample is a light brown to brownish-red irregular powder with a distinct fermented soybean aroma. Macroscopic observation shows that the particles are uniformly distributed overall, without obvious clumps or agglomerations. After hot air drying at 60℃ and sieving by 0.6 mm, the particle size distribution is concentrated, and the surface exhibits a slightly rough, matte texture, which is related to the porous structure generated by the degradation of cellulose and hemicellulose during enzymatic hydrolysis and fermentation. Compared to the dark brown of the original palm meal, the color of this sample is slightly lighter, which can be attributed to a 25% reduction in neutral detergent fiber (NDF) and changes in surface composition due to the accumulation of microbial metabolites.

[0356] Figure 17 This image shows the macroscopic morphology of the low-antigen soybean meal binding component I-B1 prepared in Example 1 of this invention. The sample is a light yellow to beige fine powder with no obvious color difference or localized discoloration. After fermentation, the sample has a slightly warm, pale yellow hue, which is related to the trace amounts of Maillard reaction products and protein hydrolysis during fermentation. Soybean meal is light yellow to light brown, and the color of this sample falls within this range. The powder has good flowability, moderate bulk density, a slight fermented sour aroma, and a pH of 5.2, indicating sufficient lactic acid bacteria fermentation.

[0357] Figure 18 The final fermented pig feed prepared in Example 1 of this invention is a cylindrical pellet, 4.0 mm in diameter and approximately 6-10 mm in length, ranging in color from light brown to yellowish-brown. The pellet surface is smooth and dense, with a mixed aroma of natural grains and fermented acidity. After conditioning and granulation at 70℃ and cooling and drying, the finished pellets have moderate hardness, with no obvious powdering or cracking, and no oil seepage is observed on the surface. The pellets have a uniform color overall, without color variations or patches, indicating good mixing uniformity. The finished product has a moisture content of 10.5 wt% and excellent storage stability.

[0358] Figure 19 Image a is a scanning electron microscope (SEM) image of porous palm meal particles I-A1 prepared in Example 1 of this invention. It shows that the sample exhibits a highly loose three-dimensional porous network structure, with uniform coverage and no large-area dense agglomeration. Figure 19The mid-magnification image (b) reveals that the pore walls are composed of a fibrous residual skeleton, exhibiting a network or sheet-like morphology, with good pore connectivity forming an open-pore structure. It also shows that spherical or rod-shaped bacterial residues adhere to the pore wall surface, proving that the combined enzymatic hydrolysis and co-fermentation with Bacillus subtilis and Saccharomyces cerevisiae effectively degraded the fiber bundle structure in palm meal, achieving a pore volume of 0.30 cubic centimeters per gram and reducing the content of neutral detergent fiber by 25%, thus providing sufficient pore space for subsequent coating treatment and nutrient adsorption. Figure 19 c is a scanning electron microscope image of the composite coated particles I-AB prepared in Example 1 of this invention. The low-magnification image clearly shows the double-layer structure. The inner palm meal core layer has a loose and porous morphology, while the outer soybean meal binding component forms a continuous coating layer. In some areas, multiple core layer particles are seen to be bonded into aggregates, showing a coexistence of mononuclear and multinuclear aggregated coated particles. The interface between the coating layer and the core layer is tightly bonded without obvious delamination or gaps. Figure 19 The high-magnification image reveals that the coating layer surface is formed by densely packed soybean meal particles with a surface roughness of submicron level. Some areas exhibit interparticle bonding bridge structures, achieving uniform coating and multi-nucleus aggregation of the palm meal core layer by the soybean meal binding components, which meets the design requirements.

[0359] Table 1 Performance summary of examples and comparative examples

[0360] As can be seen from the performance of the embodiments and comparative examples in Table 1, Examples 1-4 show a synergistic improvement in key structural parameters, soybean meal functionalization indicators, and particle stability indicators. Among them, Example 1 exhibits the most balanced pore structure, coating processing window, and finished product durability; Example 2 is more biased towards high pore volume and high fiber reduction; and Examples 3 and 4 are more prominent in the control of acid-soluble proteins and low-allergenic proteins. In the conventional comparative examples, deviations from a single variable will weaken pore structure formation, protein modification, slurry rheology, or coating quality, respectively. The synergistic effect comparative examples further show that retaining only a single advantageous component or destroying the interface construction mode is difficult to maintain both qualified particle size ratio and particle durability index at the same time, indicating that the advantage of the present invention comes from the combined effect of porous core layer, low antigen binding phase, and spray interface construction.

[0361] 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 it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any equivalent structural transformations made under the concept of the present invention and using the contents of the specification and drawings of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A fermented pig feed based on palm meal and soybean meal, characterized in that, Based on the total dry weight of the final product, it includes 20-40 wt% porous palm meal particles I-A1, 10-25 wt% low-antigen soybean meal binding component I-B1, 5-18 wt% composite coated particles I-AB, and the balance being corn, wheat or a mixture of corn and wheat. The 20-40 wt% porous palm meal particles I-A1 and the 10-25 wt% low-antigen soybean meal binding component I-B1 are the portions of the final product that do not enter the composite coated particles I-AB. The composite coated particles I-AB are formed by another portion of the porous palm meal particles I-A1 and another portion of the low-antigen soybean meal binding component I-B1. The composite coated particles I-AB are mononuclear or multinuclear aggregated coated particles with one or more of the porous palm meal particles I-A1 as the core layer and the low-antigen soybean meal binding component I-B1 as the outer coating layer or agglomerated binding layer or both the outer coating layer and the agglomerated binding layer. The outer coating layer is a continuous shell or a discontinuous shell formed on the surface of the core layer, and the agglomerated binding layer is an interparticle bonding bridge structure. The porous palm meal granules I-A1 have a pore volume of 0.15-0.45 cm³ / g, and their neutral detergent fiber content is reduced by 15-35% compared to the original palm meal used in preparing the porous palm meal granules I-A1.

2. The fermented pig feed according to claim 1, characterized in that, The acid-soluble protein in the low-antigen soybean meal binding component I-B1 accounts for 15-35 wt% of its crude protein, and the total amount of glycinin and β-conglycinin is reduced by 70-95% compared with the original soybean meal used to prepare the low-antigen soybean meal binding component I-B1; the particle size of the composite coated particles I-AB after preparation and before addition to the fermented pig feed is 0.5-2.5 mm, and at least one of the outer coating layer thickness and the characteristic thickness of the agglomeration binding layer is 10-60 μm.

3. The fermented pig feed according to claim 1, characterized in that, The porous palm meal granules I-A1 are obtained through the following steps: A1. Mix palm meal with deionized water at a mass ratio of 100:(30-45); A2. Add β-mannanase, xylanase, and protease to the mixture obtained in step A1, wherein the amount of β-mannanase added is 0.05-0.30 wt%, the amount of xylanase added is 0.02-0.20 wt%, and the amount of protease added is 0.02-0.10 wt% relative to the mass of palm meal. The amounts added are based on the mass of commercial enzyme preparations. Enzymatic hydrolysis is carried out at 45-55℃ and pH 4.5-6.5 for 4-10 hours. A3. Inoculate the material obtained in step A2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 10 g each. 6 -10 8 CFU / g and 10 5 -10 7 CFU / g, the inoculum amount is based on the total mass of the fermented wet material, and solid-state fermentation is carried out at 32-37℃ under aerobic conditions for 24-48h; A4. The fermented product obtained in step A3 is dried at 55-65℃ until the moisture content is no more than 12wt%, pulverized and sieved to 0.3-1.0mm to obtain the porous palm meal particles I-A1.

4. The fermented pig feed according to claim 1, characterized in that, The low-antigen soybean meal binding component I-B1 is prepared through the following steps: B1. Mix soybean meal and deionized water at a mass ratio of 100:(25-40); B2. Add protease to the mixture obtained in step B1, wherein the amount of protease added is 0.05-0.30 wt% relative to the mass of soybean meal, the amount added being based on the mass of a commercial enzyme preparation, and enzymatic hydrolysis is performed at 40-55°C and pH 5.5-7.0 for 2-6 hours. B3. Inoculate the material obtained in step B2 with Bacillus subtilis and Saccharomyces cerevisiae, such that the inoculation amounts of Bacillus subtilis and Saccharomyces cerevisiae are 10 g each. 6 -10 8 CFU / g and 10 5 -10 7 CFU / g, the inoculum amount is based on the total mass of the fermented wet material, solid fermentation is carried out at 30-38℃ under aerobic conditions for 24-60h, and the final pH value of the fermentation is 4.5-6.0; B4. The fermented product obtained in step B3 is dried at 50-60℃ until the moisture content is no more than 12wt%, pulverized and sieved to obtain the low-antigen soybean meal binding component I-B1.

5. The fermented pig feed according to claim 1, characterized in that, Composite coated particles I-AB are prepared through the following steps: C1. A coating slurry is obtained by mixing low-antigen soybean meal binder component I-B1 with deionized water, and porous palm meal particles I-A1 are provided as the coating substrate. The dry basis mass ratio of the porous palm meal particles I-A1 to the low-antigen soybean meal binder component I-B1 is 100:(20-80). The amount of deionized water added is adjusted to make the solid content of the coating slurry 45-75wt%. The coating slurry is kept uniformly stirred during the spraying process, and the pH value of the coating slurry is 5.0-7.

0. C2. The coating slurry obtained in step C1 is sprayed onto the surface of the substrate provided in step C1 by fluidized bed spraying under the conditions of air inlet temperature of 55-70℃ and material layer temperature of 35-45℃, to perform spray coating or spray granulation, and the spraying time is 20-60 minutes. C3. The material obtained in step C2 is dried at 45-60℃ for 1-3 hours until the moisture content is 9-12wt% to obtain the composite coated particles I-AB, the thickness of the outer coating layer and / or the characteristic thickness of the agglomeration and bonding layer is 10-60μm, and the particle size is 0.5-2.5mm.

6. The fermented pig feed according to claim 1, characterized in that, The fermented pig feed is pelleted feed with a pellet diameter of 2.0-6.0 mm and a finished product moisture content of 9-12 wt%.

7. A method for preparing fermented pig feed based on palm meal and soybean meal as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Provides porous palm meal pellets I-A1; S2. Provides low-antigen soybean meal binding component I-B1; S3. Provides composite coated particles I-AB; S4. The porous palm meal granules I-A1 provided in step S1 and the portion of the low-antigen soybean meal binding component I-B1 provided in step S2 that was not used to prepare the composite coated granules I-AB in step S3 are mixed with the composite coated granules I-AB provided in step S3 and corn, wheat or a mixture of corn and wheat according to the final product ratio, and the mixture is adjusted to a moisture content of 14-18 wt%. The mixture is then granulated at 65-75°C, cooled and dried to a finished product moisture content of 9-12 wt% to obtain the fermented pig feed.

8. The preparation method according to claim 7, characterized in that, The composite coated particles I-AB provided in step S3 are prepared by fluidized bed spraying, and the conditioning time in step S4 is 20-60s. After granulation in step S4, the material temperature is cooled to 25-40℃.

9. The preparation method according to claim 7, characterized in that, The low-antigen soybean meal binding component I-B1 provided in step S2 has a particle size D50 of 50-300 μm.

10. The preparation method according to claim 7, characterized in that, The porous palm meal granules I-A1 provided in step S1 and the low-antigen soybean meal binding component I-B1 provided in step S2 are both obtained by solid-state fermentation using Bacillus subtilis and Saccharomyces cerevisiae, wherein the Bacillus subtilis is prepared with a viable count of 10-1. 9 -10 11 Commercially available starter culture powder with a CFU / g concentration, using brewer's yeast with a live cell count of 10-10. 8 -10 10 Commercial dry yeast at CFU / g.

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