A method and device for preparing low-purine raw materials for healthy soybean products

Abstract

The present application relates to the field of functional food preparation technology, and particularly relates to a low purine healthy bean product raw material pretreatment preparation method and device, which comprises raw material screening and impurity removal, dry bean raw material is put into a screening assembly from a feeding hopper, a screening motor is started to drive the screening frame to reciprocatingly vibrate, sand, stones, shriveled beans, worm-eaten beans and straw impurities are screened out, and the pure bean material with complete particles is screened out and falls into a collecting hopper to complete the preliminary purification of the raw material, dynamic water washing is performed in the cylinder to separate purine, the pure bean material is sent into a rotating cylinder in the inner part of the outer cylinder through a first spiral conveying cylinder, clean water is supplied into the rotating cylinder to perform dynamic water washing, the connection structure of the combined purine and soybean protein is destroyed, and the purine is separated out. The present application can effectively solve the problem that the traditional high-temperature boiling method causes the raw material to mature and cannot be used to make fresh bean products, and the pretreated bean material can be normally used for the processing of various products such as bean curd, fresh soybean milk, dried tofu and the like.

Description

Technical Field

[0001] This invention relates to the field of soybean fermentation technology, and in particular to a method and apparatus for pre-treatment and preparation of low-purine healthy soybean product raw materials. Background Technology

[0002] Soy products are plant-based protein foods made from soybeans, black beans, and other legumes. With their high protein, low fat, and balanced nutrition, they are widely used in food products such as soy milk, tofu, dried tofu, and bean curd sticks. As the number of people with hyperuricemia and gout continues to grow, low-purine soy products, as a type of functional health food that adjusts the nutritional properties of food, are experiencing increasing market demand.

[0003] Currently, there are significant limitations to purine reduction technologies for soybean raw materials: when using high-temperature boiling for purine removal, water temperatures exceeding 60°C can easily cause denaturation of soybean protein and oxidation of fats, resulting in complete cooking of the raw materials, making them unsuitable for the production of fresh soybean products such as tofu and soy milk. Salting out and adsorption methods are prone to introducing exogenous impurities during the purine removal process, and the adsorbent is difficult to regenerate, leading to high production costs. Ultrasonic purine removal technology not only has high energy consumption but is also difficult to adapt to industrial continuous mass production scenarios. Existing technologies cannot efficiently reduce purine content while preserving the original processing properties of soybean raw materials, thus hindering the industrialization of low-purine functional soybean products. Summary of the Invention

[0004] The purpose of this invention is to address the following shortcomings in existing technologies: when using high-temperature boiling for purine removal, water temperatures exceeding 60°C easily cause denaturation of soybean protein and oxidation of fats, resulting in complete cooking of the raw materials, making them unsuitable for the production of fresh soy products such as tofu and soy milk; salting out and adsorption methods easily introduce exogenous impurities during purine removal, and the adsorbent is difficult to regenerate, leading to high production costs; ultrasonic purine removal processes not only have high energy consumption but are also difficult to adapt to industrial continuous mass production scenarios. Existing technologies cannot efficiently reduce purine content while preserving the original processing properties of soybean raw materials, thus hindering the industrialization of low-purine functional soy products. Therefore, this invention proposes a method and apparatus for pre-treatment and preparation of low-purine healthy soy product raw materials.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for pre-treating and preparing low-purine healthy soy product raw materials includes the following steps: S1: Raw material screening and impurity removal. The dry bean raw materials are fed into the screening component from the feed hopper. The screening motor is started to drive the screening frame to vibrate back and forth, removing sand, shriveled grains, insect-damaged beans, straw and other impurities. The pure beans with intact particles are screened out and fall into the collection hopper, completing the initial purification of the raw materials. S2: Dynamic water washing to remove purines inside the cylinder. The pure soybeans are sent into the rotating cylinder inside the outer cylinder through the first spiral conveyor. Clean water is introduced into the rotating cylinder for dynamic water washing, which breaks the connection structure between the bound purines and soybean protein, and promotes the precipitation of purines. S3: Initial draining and secondary reverse rinsing. After dynamic water washing, the beans are initially drained through the permeable holes, and then transported to the box through the conveying pipe and the second spiral conveyor and fall onto the filter plate. After sealing the space below the filter plate, water is flushed back to the beans through the hose. The rinsing wastewater is discharged through the drain hole to remove residual purines from the surface and crevices of the beans. S4: Low-temperature microbial fermentation and degradation, stop reverse flushing, add food-grade purine-degrading microbial inoculants to the soybeans in the box, turn the soybeans to make full contact between the microbial inoculants and the raw materials, and use microorganisms to decompose the residual bound purines inside the soybeans; S5: Low-temperature hot air drying protects color and nutrients. During the fermentation process, low-temperature hot air at 42-50℃ is introduced simultaneously. Hot air, fermentation waste gas and excess water vapor are discharged from the drain hole, which regulates the moisture content of soybeans and inhibits the activity of polyphenol oxidase, thus preserving the original nutrients of soybeans. S6: Finished product discharge. After the drying and fermentation processes are completed, the box is unsealed, the sealing cover is opened, and the pre-treated low-purine soybeans are taken out, completing the single batch processing and entering the next round of continuous production.

[0006] As a preferred embodiment, in step S2, clean water is supplied to the rotating drum through the water inlet pipe and the annular pipe connected to the pump. The drive motor drives the rotating drum to alternately rotate forward and backward at low speed. Multiple silicone protrusions on the inner wall of the rotating drum gently rub the surface of the soybeans, continuously breaking the connection structure between bound purines and soybean protein. The water temperature pumped in through the water inlet pipe is controlled at 42-50℃, which is below the critical temperature for protein denaturation throughout the process, thus avoiding damage to the soybeans and fat oxidation.

[0007] As a preferred embodiment, in step S3, the servo motor is started to drive the L-shaped sealing plate to rotate and fit against the lower surface of the filter plate, thereby sealing the space below the filter plate. Clean water is flushed upwards and backwards through the hose to rinse the soybeans above the filter plate, while wastewater carrying residual purines is discharged from the drain hole on the side wall of the box.

[0008] As a preferred embodiment, steps S4 and S5 are performed simultaneously. The reciprocating screw and its matching drive motor drive the T-shaped slider to move back and forth. The rake rod below the T-shaped slider turns the soybeans over the entire area. Low-temperature hot air is blown onto the soybeans through the corrugated pipe and the air outlet at the bottom of the T-shaped slider. A one-way valve at the drain hole prevents the backflow of outside air and bacteria. Hot air, fermentation waste gas, and excess moisture are all discharged from the drain hole. The low-temperature hot air at 42-50℃ dries the soybeans while inhibiting enzymatic browning and retaining nutrients such as B vitamins and unsaturated fatty acids in the soybeans.

[0009] An apparatus for the pretreatment and preparation method of low-purine healthy soy product raw materials includes a base, on which a screening component, a rinsing component, a conveying component and a drying and fermentation component are provided. The screening component includes a screening frame fixedly installed on the base, and a screening frame is slidably connected to the screening frame. The rinsing assembly includes an outer cylinder fixedly mounted on the base, and a rotating cylinder is rotatably disposed inside the outer cylinder; The drying and fermentation assembly includes a box fixedly mounted on the base, a filter plate fixedly connected inside the box, and a hot air blower fixedly connected to the box.

[0010] As a preferred embodiment, the conveying assembly includes a first spiral conveying cylinder and a second spiral conveying cylinder. Both the first and second spiral conveying cylinders are fixedly mounted on the upper surface of the base. A collecting hopper is fixedly connected to the first spiral conveying cylinder, and the collecting hopper is located below the screening frame. A feed inlet for connecting the first spiral conveying cylinder is provided on one side of the rotating cylinder. A feed hole for connecting the second spiral conveying cylinder is provided on the housing. The second spiral conveying cylinder is connected to the rotating cylinder through a conveying pipe, and a solenoid valve is provided on the conveying pipe.

[0011] As a preferred embodiment, the screening frame is fixedly connected to a feed hopper and two symmetrically arranged fixed blocks. A rotating shaft is rotatably connected between the two fixed blocks, and two rotating blocks are fixedly connected to the rotating shaft. A screening motor is fixedly connected to one of the fixed blocks, and the drive end of the screening motor is fixedly connected to the rotating shaft. A hollow protective cylinder is fixedly connected between the two fixed blocks and is sleeved outside the rotating shaft. Both sides of the screening frame have oblique openings, and a blocking plate is slidably connected to each oblique opening. Both blocking plates are fixedly connected to the screening frame. A fixing strip is fixedly connected to one side of each blocking plate, and an I-shaped block is slidably connected to the fixing strip. A protrusion is fixedly connected to one side of the I-shaped block, and the two protrusions are rotatably connected to the two rotating blocks respectively.

[0012] As a preferred embodiment, a drive motor is fixedly connected to the outer cylinder, and the drive end of the drive motor is fixedly connected to the rotating cylinder. A plurality of support balls arranged in a circular array are rotatably connected to the bottom of the rotating cylinder. An annular groove for connecting the support balls is opened on the lower inner wall of the outer cylinder. An annular tube is fixedly connected to the inner wall of the outer cylinder. The annular tube is rotatably connected to the rotating cylinder. A plurality of water inlets are opened on the side of the annular tube near the rotating cylinder. A plurality of water permeable holes are opened on the rotating cylinder. A water inlet pipe is fixedly connected to the annular tube. A plurality of silicone protrusions are fixedly connected to the inner wall of the rotating cylinder.

[0013] As a preferred embodiment, a servo motor is fixedly connected to the housing, a fixed shaft is fixedly connected to the drive end of the servo motor, a sealing plate with an L-shaped cross-section is fixedly connected to the fixed shaft, an electromagnetic brake is provided at the drive end of the servo motor, a flexible hose is fixedly connected to the sealing plate, a sealing cover is connected to one side of the housing by multiple bolts, and multiple drainage holes are provided on the inner wall of the other side of the housing, with one-way valves provided on the flexible hose and each of the drainage holes.

[0014] As a preferred embodiment, a drive motor is fixedly connected to the housing, and a reciprocating lead screw is fixedly connected to the drive end of the drive motor. A T-shaped slider is threaded onto the reciprocating lead screw. The T-shaped slider is slidably connected to the upper inner wall of the housing. The T-shaped slider is connected to the hot air blower through a bellows. Multiple air outlets communicating with the bellows are opened on the lower surface of the T-shaped slider. Multiple rake rods are fixedly connected to the lower surface of the T-shaped slider.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The entire process is carried out at low temperatures, preserving the original processing properties of the raw materials. The temperature of the entire process and equipment is controlled at 42-50℃, which is always below the critical temperature for denaturation of soybean protein and oxidation of fat. This can effectively solve the problem that the raw materials are cooked and cannot be used to make fresh soybean products due to the traditional high-temperature boiling method. The pre-treated soybeans can be used normally for processing various products such as tofu, fresh soy milk, and dried tofu. 2. Pure physical + biological composite depurination, without the introduction of exogenous impurities. It adopts a composite depurination process of "dynamic water washing to break the bond + reverse rinsing to remove residues + microbial-assisted degradation". It eliminates the chemical reagents and adsorption materials required by salting out and adsorption methods, and will not introduce exogenous impurities into the raw materials. At the same time, it eliminates the adsorbent regeneration process, which greatly reduces the production consumables and operation and maintenance costs. 3. Integrated continuous equipment, suitable for industrial mass production and with lower energy consumption. This device integrates screening, multi-stage washing, conveying, fermentation and drying processes. It relies on screw conveying to achieve uninterrupted material flow and form a continuous production line. Compared with high-energy-consuming ultrasonic depurination equipment, this device mainly uses mechanical transmission and conventional hot air, which significantly reduces the overall energy consumption and can be well adapted to large-scale industrial continuous production scenarios. 4. Multi-stage purine removal design, high removal efficiency and stable effect. The free and bound purines are removed through three processes: dynamic water washing of rotating drum, reverse rinsing of the chamber and microbial fermentation. Combined with the structure of silicone bump mechanically breaking purine bonds and rake rod uniform material turning, it ensures that purines are fully removed and the pre-treated quality of different batches of raw materials is uniform and stable. 5. Low-temperature hot air drying protects color and nutrients, improving the quality of raw materials. Using a mobile low-temperature hot air drying system at 42-50℃, the activity of polyphenol oxidase in soybeans can be effectively inhibited, preventing enzymatic browning of raw materials. At the same time, it fully preserves natural nutrients such as B vitamins and unsaturated fatty acids, improving the quality and taste of finished soybean products. 6. Wide range of applications and strong process adjustability: The equipment can be adapted to various soy product raw materials such as soybeans and black beans. At the same time, the washing time, fermentation cycle, hot air temperature and other process parameters can be flexibly adjusted according to the initial purine content of the raw materials and product index requirements. It has strong versatility and can meet the production needs of different types of low-purine soy products. Attached Figure Description

[0016] Figure 1 This is a flowchart of a method for preparing low-purine healthy soy product raw materials according to the present invention; Figure 2 This is a front structural schematic diagram of a pretreatment and preparation device for low-purine healthy soy products proposed in this invention. Figure 3 This is a side view of a pretreatment device for preparing low-purine healthy soy products according to the present invention. Figure 4 This is a top view schematic diagram of a pretreatment and preparation device for low-purine healthy soy products proposed in this invention; Figure 5 This is a schematic diagram of the back structure of a pretreatment and preparation device for low-purine healthy soy products proposed in this invention; Figure 6 This is a partial front view of the internal structure of a pretreatment and preparation device for low-purine healthy soy products proposed in this invention. Figure 7 This is a partial frontal internal structural diagram of the housing, filter plate, and hot air blower in this invention. Figure 8 This is a partial front view of the internal structure of the housing, T-shaped slider, and reciprocating lead screw in this invention. Figure 9 for Figure 4 A magnified schematic diagram of the structure of part A in the diagram; Figure 10 for Figure 6 A magnified schematic diagram of the partial structure of B in the diagram; Figure 11 for Figure 7 A magnified schematic diagram of the structure of C.

[0017] In the diagram: 1. Base, 2. Screening frame, 3. Feed hopper, 4. Rotating block, 5. Outer cylinder, 6. First spiral conveyor cylinder, 7. Collection hopper, 8. Box body, 9. Second spiral conveyor cylinder, 10. Support ball bearing, 11. Hot air blower, 12. Water inlet pipe, 13. Sealing cover plate, 14. Screening frame, 15. Hollow protective cylinder, 16. Fixing block, 17. Drain hole, 18. Hose, 19. Filter plate, 20. Rotating cylinder, 21. Sealing block plate, 22. Reciprocating screw, 23. T-shaped slider, 24. Corrugated pipe, 25. Rake rod, 26. Servo motor, 27. Annular pipe, 28. Silicone protrusion, 29. Water permeable hole, 30. Fixing strip, 31. I-shaped block, 32. Protrusion, 33. Rotating shaft, 34. Blocking plate, 35. Conveying pipe. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Reference Figures 1-11 A method for preparing low-purine healthy soy product raw materials through pretreatment includes the following steps: S1: Raw material screening and impurity removal. Dry bean raw materials are fed into the screening component from the feed hopper 3. The screening motor is started to drive the screening frame 14 to vibrate back and forth to remove sand, gravel, shriveled grains, insect-infested beans, straw and other impurities. Pure bean materials with intact particles are screened out and fall into the collection hopper 7 to complete the initial purification of raw materials. S2: Dynamic water washing to remove purines inside the cylinder. Pure soybeans are fed into the rotating cylinder 20 inside the outer cylinder 5 via the first spiral conveyor cylinder 6. Clean water is introduced into the rotating cylinder 20 for dynamic water washing, which breaks the connection structure between bound purines and soybean protein, and promotes the precipitation of purines. The water washing time is controlled at 20-40 minutes. S3: Initial draining and secondary reverse rinsing. After dynamic water washing, the soybeans are initially drained through the permeable holes 29, and then transported to the box 8 through the conveying pipe 35 and the second spiral conveyor 9 and fall onto the filter plate 19. After sealing the space below the filter plate 19, water is flushed back to the soybeans through the hose 18. The rinsing wastewater is discharged through the drain hole 17 to remove residual purines from the surface and crevices of the soybeans. S4: Low-temperature microbial fermentation and degradation, stop reverse flushing, add food-grade purine-degrading bacteria to the soybeans in box 8, the amount of food-grade purine-degrading bacteria added is 0.3%-1.0% of the mass of soybeans, turn the soybeans to make full contact between the bacteria and the raw materials, and use microorganisms to decompose the residual bound purines inside the soybeans. S5: Low-temperature hot air drying protects color and nutrients. During the fermentation process, low-temperature hot air at 42-50℃ is introduced simultaneously. The drying time is 15-30 minutes. Hot air, fermentation waste gas and excess water vapor are discharged from the drain hole 17 to regulate the moisture content of the soybeans. At the same time, the activity of polyphenol oxidase is inhibited to retain the original nutrients of the soybeans. The fermentation time is 10-24 hours. Microorganisms decompose the bound purines and nucleotides inside the soybeans that are difficult to wash away with water. S6: Finished product discharge. After the drying and fermentation processes are completed, the sealing of box 8 is released, the sealing cover 13 is opened and the pre-treated low-purine soybeans are taken out, completing the single batch processing and entering the next round of continuous production.

[0020] In step S2, clean water is supplied to the rotating drum 20 through the water inlet pipe 12 and the annular pipe 27 connected to the pump. The drive motor drives the rotating drum 20 to alternate forward and reverse at low speed. Multiple silicone protrusions 28 on the inner wall of the rotating drum 20 gently rub the surface of the soybeans, continuously breaking the connection structure between bound purines and soybean protein. The water temperature pumped in by the water inlet pipe 12 is controlled at 42-50℃, which is below the critical temperature for protein denaturation throughout the process, thus avoiding damage to the soybeans and fat oxidation.

[0021] In step S3, the servo motor 26 is started to drive the L-shaped sealing plate 21 to rotate and fit against the lower surface of the filter plate 19, thereby sealing the space below the filter plate 19. Clean water is flushed upwards and backwards through the hose 18 to wash the soybeans above the filter plate 19, and the wastewater carrying residual purines is discharged from the drain hole 17 on the side wall of the box 8.

[0022] Steps S4 and S5 are performed simultaneously. The reciprocating screw 22, equipped with a drive motor, drives the T-shaped slider 23 to move back and forth. The rake rod 25 below the T-shaped slider 23 turns the soybeans over the entire area. Low-temperature hot air is blown onto the soybeans through the corrugated pipe 24 and the air outlet at the bottom of the T-shaped slider 23. The one-way valve set at the drain hole 17 prevents the backflow of outside air and bacteria. Hot air, fermentation waste gas, and excess moisture are discharged from the drain hole 17. The low-temperature hot air at 42-50℃ dries the soybeans while inhibiting enzymatic browning and retaining nutrients such as B vitamins and unsaturated fatty acids in the soybeans.

[0023] An apparatus for pre-treatment preparation of low-purine healthy soy product raw materials includes a base 1, on which a screening component, a rinsing component, a conveying component, and a drying and fermentation component are arranged. The screening component includes a screening frame 2 fixedly installed on the base 1, and a screening frame 14 slidably connected to the screening frame 2. The rinsing component includes an outer cylinder 5 fixedly installed on the base 1, and a rotating cylinder 20 rotatably installed inside the outer cylinder 5. The drying and fermentation component includes a box 8 fixedly installed on the base 1, a filter plate 19 fixedly connected inside the box 8, and a hot air blower 11 fixedly connected to the box 8.

[0024] The conveying assembly includes a first spiral conveyor 6 and a second spiral conveyor 9. Both the first spiral conveyor 6 and the second spiral conveyor 9 are fixedly installed on the upper surface of the base 1. A collection hopper 7 is fixedly connected to the first spiral conveyor 6. The collection hopper 7 is used to receive the pure soybeans after screening. The collection hopper 7 is located below the screening frame 14. A feed inlet for connecting the first spiral conveyor 6 is opened on one side of the rotating cylinder 20. A feed hole for connecting the second spiral conveyor 9 is opened on the housing 8. The second spiral conveyor 9 is connected to the rotating cylinder 20 through a conveying pipe 35. The conveying pipe 35 and the second spiral conveyor 9 are fixedly connected. The conveying pipe 35 and the rotating cylinder 20 are rotatably connected and have good sealing performance. A solenoid valve is installed on the conveying pipe 35.

[0025] The screening frame 2 is fixedly connected to a feed hopper 3 and two symmetrically arranged fixed blocks 16. A rotating shaft 33 is rotatably connected between the two fixed blocks 16. Two rotating blocks 4 are fixedly connected to the rotating shaft 33. A screening motor is fixedly connected to one of the fixed blocks 16. The drive end of the screening motor is fixedly connected to the rotating shaft 33. A hollow protective cylinder 15 is fixedly connected between the two fixed blocks 16. The hollow protective cylinder 15 is sleeved on the outside of the rotating shaft 33. Both sides of the screening frame 2 are provided with slanted openings. A blocking plate 34 is slidably connected in each slanted opening. Both blocking plates 34 are fixedly connected to the screening frame 14. A fixing strip 30 is fixedly connected to one side of each blocking plate 34. An I-shaped block 31 is slidably connected in the fixing strip 30. The I-shaped block 31 cannot be separated from the fixing strip 30. The I-shaped block 31 can only slide vertically relative to the fixing strip 30. A protrusion 32 is fixedly connected to one side of the I-shaped block 31. The two protrusions 32 are rotatably connected to the two rotating blocks 4 respectively.

[0026] A drive motor is fixedly connected to the outer cylinder 5. The drive end of the drive motor is fixedly connected to the rotating cylinder 20. Multiple support balls 10 arranged in a ring array are rotatably connected to the bottom of the rotating cylinder 20. An annular groove for connecting the support balls 10 is opened on the lower inner wall of the outer cylinder 5. An annular tube 27 is fixedly connected to the inner wall of the outer cylinder 5. The annular tube 27 is rotatably connected to the rotating cylinder 20. Multiple water inlets are opened on the side of the annular tube 27 near the rotating cylinder 20. Multiple water permeable holes 29 are opened on the rotating cylinder 20. A water inlet pipe 12 is fixedly connected to the annular tube 27. Multiple silicone protrusions 28 are fixedly connected to the inner wall of the rotating cylinder 20. The silicone protrusions 28 are used for stirring and rubbing the beans.

[0027] A servo motor 26 is fixedly connected to the housing 8. A fixed shaft is fixedly connected to the drive end of the servo motor 26. A sealing plate 21 with an L-shaped cross-section is fixedly connected to the fixed shaft. An electromagnetic brake is provided at the drive end of the servo motor 26. A hose 18 is fixedly connected to the sealing plate 21. A sealing cover 13 is connected to one side of the housing 8 by multiple bolts. Multiple drainage holes 17 are provided on the inner wall of the other side of the housing 8. A one-way valve is provided on the hose 18 and each drainage hole 17.

[0028] A drive motor is fixedly connected to the housing 8. A reciprocating lead screw 22 is fixedly connected to the drive end of the drive motor. A T-shaped slider 23 is threadedly connected to the reciprocating lead screw 22. The T-shaped slider 23 is slidably connected to the upper inner wall of the housing 8. The T-shaped slider 23 is connected to the hot air blower 11 through a bellows 24. Multiple air outlets communicating with the bellows 24 are opened on the lower surface of the T-shaped slider 23. Multiple rake rods 25 are fixedly connected to the lower surface of the T-shaped slider 23.

[0029] The operator feeds the dried bean raw materials into the screening frame 14 through the feed hopper 3, starts the screening motor, and the motor drives the rotating shaft 33 and the rotating block 4 to rotate back and forth synchronously. When the rotating block 4 rotates, it drives the protrusion 32 to move. The protrusion 32 drives the I-shaped block 31 and the fixed strip 30 to slide relative to each other. The fixed strip 30 will drive the blocking plate 34 to slide. Through the linkage of the protrusion 32, the I-shaped block 31 and the fixed strip 30, the blocking plate 34 and the screening frame 14 are pulled to vibrate back and forth along the inclined opening. Using the principle of vibrating screening, impurities such as sand, shriveled grains, insect-damaged beans, and straw are removed. The whole and pure bean material falls into the collection hopper 7, completing the raw material purification.

[0030] The soybeans in the collection hopper 7 are fed into the rotating drum 20 by the first spiral conveyor 6. External clean water enters the rotating drum 20 through the water inlet pipe 12, the annular pipe 27, the water inlet, and the water permeable hole 29 under the action of the water pump, completely submerging the soybeans. The drive motor drives the rotating drum 20 to alternately rotate forward and backward at low speed. The silicone protrusions 28 inside the rotating drum 20 gently rub the surface of the soybeans, breaking the connection structure between the bound purines and soybean protein, and promoting the precipitation of purines. The water temperature is controlled at 42-50℃ throughout the process, so as not to cause denaturation of soybean protein or oxidation of fat. The water generated from washing is initially drained through the water permeable hole 29.

[0031] After washing, the solenoid valve on the conveying pipe 35 is opened, and the soybeans are conveyed through the conveying pipe 35 and the second spiral conveying cylinder 9 into the box 8 and fall above the filter plate 19. The servo motor 26 is started to drive the sealing plate 21 to rotate and adhere to the lower surface of the filter plate 19, that is, to seal the area below the filter plate 19. The water flows through the hose 18 and flows in the opposite direction to the soybeans above the filter plate 19, gradually washing away the residual purines on the surface and in the gaps of the soybeans. The rinsing wastewater is discharged from the drain hole 17, further improving the purine removal rate.

[0032] After the reverse rinsing is completed, food-grade purine-degrading bacteria are added to the soybeans in the chamber 8. The drive motor of the reciprocating screw 22 is started, which drives the T-shaped slider 23 to move back and forth along the reciprocating screw 22. The rake rod 25 continuously turns the soybeans to ensure that the bacteria and raw materials are in full contact and degrade residual bound purines. At the same time, the hot air blower 11 is started, and low-temperature hot air of 42-50℃ is blown out evenly through the corrugated pipe 24 and the air outlet at the bottom of the T-shaped slider 23 to provide oxygen for the aerobic bacteria and maintain the fermentation temperature. The moving air supply, together with the rake rod 25, turns the soybeans over the entire area, which inhibits the activity of polyphenol oxidase while drying the soybeans, avoids browning of the soybeans, and retains various original nutrients of the soybeans. Fermentation waste gas and water vapor can be discharged through the drain hole 17, and the one-way valve effectively prevents the backflow of external bacteria.

[0033] After the finished product is discharged, fermented, and dried, all power equipment is shut down, the sealing cover 13 is removed, and the pre-treated low-purine soybeans are taken out. After the equipment is reset, the next batch can be processed, realizing industrial continuous cycle production.

[0034] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for pre-treating and preparing low-purine healthy soy product raw materials, characterized in that, Includes the following steps: S1: Raw material screening and impurity removal. Dry bean raw materials are fed into the screening component from the feed hopper (3). The screening motor is started to drive the screening frame (14) to vibrate back and forth to remove sand, shriveled grains, insect-damaged beans, straw and other impurities. Pure bean material with intact particles is screened out and falls into the collection hopper (7) to complete the initial purification of raw materials. S2: Dynamic water washing to remove purines in the cylinder. The pure soybean material is sent into the rotating cylinder (20) inside the outer cylinder (5) through the first spiral conveyor cylinder (6). Clean water is introduced into the rotating cylinder (20) for dynamic water washing, which breaks the connection structure between the bound purine and soybean protein and promotes the precipitation of purine. S3: Initial draining and secondary reverse rinsing. After dynamic water washing, the soybeans are initially drained through the permeable holes (29), and then transported to the box (8) through the conveying pipe (35) and the second spiral conveying cylinder (9) and fall onto the filter plate (19). After sealing the space below the filter plate (19), the soybeans are flushed in reverse through the hose (18). The rinsing wastewater is discharged through the drain hole (17) to remove residual purines from the surface and crevices of the soybeans. S4: Low-temperature bacterial fermentation and degradation, stop reverse flushing, put food-grade purine-degrading bacteria into the soybeans in the box (8), turn the soybeans to make the bacteria and raw materials fully contact each other, and use microorganisms to decompose the residual bound purines inside the soybeans; S5: Low-temperature hot air drying protects color and nutrition. During the fermentation process, low-temperature hot air at 42-50℃ is introduced simultaneously. Hot air, fermentation waste gas and excess water vapor are discharged from the drain hole (17) to regulate the moisture content of soybeans and inhibit the activity of polyphenol oxidase, thus preserving the original nutrients of soybeans. S6: Finished product discharge. After the drying and fermentation process is completed, the box (8) is unsealed, the sealing cover (13) is opened and the pre-treated low-purine soybeans are taken out to complete the single batch processing and enter the next round of continuous production.

2. The method for preparing low-purine healthy soy product raw materials according to claim 1, characterized in that, In step S2, clean water is supplied to the rotating drum (20) through the water inlet pipe (12) and the annular pipe (27) connected to the pump. The drive motor drives the rotating drum (20) to alternate forward and reverse at low speed. Multiple silicone protrusions (28) on the inner wall of the rotating drum (20) gently rub the surface of the soybean grains, continuously destroying the connection structure between bound purines and soybean protein. The water temperature pumped in by the water inlet pipe (12) is controlled at 42-50℃, which is lower than the critical temperature for protein denaturation throughout the process, thus avoiding damage to the soybean grains and fat oxidation.

3. The method for preparing low-purine healthy soy product raw materials according to claim 2, characterized in that, In step S3, the servo motor (26) is started to drive the L-shaped sealing plate (21) to rotate and fit against the lower surface of the filter plate (19), thereby sealing the space below the filter plate (19). Clean water is flushed upwards and backwards through the hose (18) to wash the soybeans above the filter plate (19), and wastewater carrying residual purines is discharged from the drain hole (17) on the side wall of the box (8).

4. The method for preparing low-purine healthy soy product raw materials according to claim 3, characterized in that, Steps S4 and S5 are performed simultaneously. The reciprocating screw (22) and the matching drive motor drive the T-shaped slider (23) to move back and forth. The rake rod (25) below the T-shaped slider (23) turns the soybeans over in the whole area. Low-temperature hot air is blown onto the soybeans through the corrugated pipe (24) and the air outlet at the bottom of the T-shaped slider (23). The one-way valve set at the drain hole (17) prevents the backflow of external air and bacteria. Hot air, fermentation waste gas and excess water vapor are discharged from the drain hole (17). The low-temperature hot air at 42-50℃ dries the soybeans while inhibiting enzymatic browning and retaining the B vitamins, unsaturated fatty acids and other nutrients of the soybeans.

5. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, Includes a base (1), on which a screening component, a rinsing component, a conveying component and a drying and fermentation component are provided. The screening component includes a screening frame (2) fixedly installed on the base (1), and a screening frame (14) is slidably connected to the screening frame (2). The rinsing assembly includes an outer cylinder (5) fixedly installed on the base (1), and a rotating cylinder (20) is rotatably disposed inside the outer cylinder (5). The drying and fermentation assembly includes a box (8) fixedly mounted on the base (1), a filter plate (19) fixedly connected inside the box (8), and a hot air blower (11) fixedly connected to the box (8).

6. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, The conveying assembly includes a first spiral conveying cylinder (6) and a second spiral conveying cylinder (9). The first spiral conveying cylinder (6) and the second spiral conveying cylinder (9) are both fixedly installed on the upper surface of the base (1). A collection hopper (7) is fixedly connected to the first spiral conveying cylinder (6). The collection hopper (7) is located below the screening frame (14). A feed port for connecting the first spiral conveying cylinder (6) is opened on one side of the rotating cylinder (20). A feed hole for connecting the second spiral conveying cylinder (9) is opened on the box body (8). The second spiral conveying cylinder (9) is connected to the rotating cylinder (20) through a conveying pipe (35). A solenoid valve is provided on the conveying pipe (35).

7. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, The screening frame (2) is fixedly connected to a feed hopper (3) and two symmetrically arranged fixed blocks (16). A rotating shaft (33) is rotatably connected between the two fixed blocks (16). Two rotating blocks (4) are fixedly connected to the rotating shaft (33). A screening motor is fixedly connected to one of the fixed blocks (16). The drive end of the screening motor is fixedly connected to the rotating shaft (33). A hollow protective cylinder (15) is fixedly connected between the two fixed blocks (16). The hollow protective cylinder (15) is sleeved on the rotating shaft (4). Outside the shaft (33), both sides of the screening frame (2) are provided with slanted openings. Each slanted opening is slidably connected to a blocking plate (34). Both blocking plates (34) are fixedly connected to the screening frame (14). Each blocking plate (34) is fixedly connected to one side with a fixing strip (30). An I-shaped block (31) is slidably connected inside the fixing strip (30). A protrusion (32) is fixedly connected to one side of the I-shaped block (31). The two protrusions (32) are rotatably connected to the two rotating blocks (4) respectively.

8. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, A drive motor is fixedly connected to the outer cylinder (5). The drive end of the drive motor is fixedly connected to the rotating cylinder (20). A plurality of support balls (10) arranged in a ring array are rotatably connected to the bottom of the rotating cylinder (20). An annular groove for connecting the support balls (10) is opened on the lower inner wall of the outer cylinder (5). An annular tube (27) is fixedly connected to the inner wall of the outer cylinder (5). The annular tube (27) is rotatably connected to the rotating cylinder (20). A plurality of water inlets are opened on the side of the annular tube (27) near the rotating cylinder (20). A plurality of water permeable holes (29) are opened on the rotating cylinder (20). A water inlet pipe (12) is fixedly connected to the annular tube (27). A plurality of silicone protrusions (28) are fixedly connected to the inner wall of the rotating cylinder (20).

9. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, A servo motor (26) is fixedly connected to the housing (8). A fixed shaft is fixedly connected to the drive end of the servo motor (26). A sealing plate (21) with an L-shaped cross-section is fixedly connected to the fixed shaft. An electromagnetic brake is provided at the drive end of the servo motor (26). A hose (18) is fixedly connected to the sealing plate (21). A sealing cover plate (13) is connected to one side of the housing (8) by multiple bolts. Multiple drainage holes (17) are opened on the inner wall of the other side of the housing (8). A one-way valve is provided on the hose (18) and each of the drainage holes (17).

10. An apparatus for preparing low-purine healthy soy product raw materials according to claim 4, characterized in that, A drive motor is fixedly connected to the housing (8), and a reciprocating lead screw (22) is fixedly connected to the drive end of the drive motor. A T-shaped slider (23) is threadedly connected to the reciprocating lead screw (22). The T-shaped slider (23) is slidably connected to the upper inner wall of the housing (8). The T-shaped slider (23) is connected to the hot air blower (11) through a bellows pipe (24). The lower surface of the T-shaped slider (23) is provided with multiple air outlets communicating with the bellows pipe (24). Multiple rake rods (25) are fixedly connected to the lower surface of the T-shaped slider (23).

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