Twin-screw extruder and grain processing equipment

Abstract

The embodiment of the utility model discloses a double-screw extruder and grain processing equipment. The double-screw extruder comprises a barrel body, the two mandrels are arranged in the cylinder body in parallel, and the mandrels extend in the axial direction of the cylinder body; the processing module is sleeved on the core shaft; the mandrel is combined and fixed to the output end of the driving mechanism and can drive the machining module to rotate relative to the barrel under the action of the driving mechanism so as to machine the materials; the twin-screw extruder is divided into six processing sections in the material conveying direction, the six processing sections are a feeding section, a conveying section, a mixing section, a cooking section, a melting section and a transfer section in sequence, and a feeding port of the barrel is correspondingly formed in the feeding section; each processing section is provided with a forward conveying module, and the conveying section, the mixing section, the cooking section and the melting section are provided with forward meshing modules; the cooking section and the melting section are respectively provided with a reverse conveying module; the mixing section and the cooking section are respectively provided with a reverse meshing module; and the conveying section and the melting section are both provided with pressure rings, so that the whole grains are extruded.

Description

Technical Field

[0001] The utility model relates to the technical field of grain processing equipment, and more specifically, to a twin-screw extruder and grain processing equipment. Background Art

[0002] High-fiber cereals usually refer to cereal grains, including the germ and cortex. In order to retain its nutritional value, the whole grain is usually crushed during the flour processing. However, during the flour grinding process, the grain's own biological enzymes are activated, and on the other hand, the grains are rich in unsaturated fatty acids and are exposed to oxygen during the flour grinding process. Under the combined action of high temperature, oxygen and highly active enzymes, oxidation and rancidity easily occur, causing quality deterioration.

[0003] At present, extrusion puffing technology is generally used to process grains. Usually, the grains are crushed to a certain fineness and then fed into the extruder. However, under the action of high temperature, high pressure and high shear force of the extruder, the starch is further degraded after gelatinization, and the Maillard reaction occurs with the exposed amino groups, producing a puffed paste taste, which will affect the flavor quality of the final product and reduce the product acceptability. In addition, due to the tough texture of the grain bran, the processed grain bran has a strong bran taste and a rough texture due to the limitations of the process and equipment, which cannot meet the requirements of creative food. Utility Model Content

[0004] In view of the above problems, one purpose of the utility model is to provide a twin-screw extruder that can solve the problems of quality deterioration in the grain crushing process, the sticky taste of grains after extrusion and puffing modification, the destruction of the grain cortex and low degree of degradation, which cause the rough taste of the terminal grain products.

[0005] Another object of the utility model is to provide a grain processing device comprising the above-mentioned twin-screw extruder.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] According to one aspect of the utility model, a twin-screw extruder is provided, comprising:

[0008] A cylinder, the cylinder comprising a feed inlet;

[0009] Two core shafts are arranged in parallel in the cylinder, and the core shafts are extended along the axial direction of the cylinder;

[0010] a processing module sleeved on the mandrel, the processing module comprising a forward conveying module, a reverse conveying module, a forward meshing module, a reverse meshing module and a pressure ring; and

[0011] A driving mechanism, wherein the core shaft is fixedly coupled to an output end of the driving mechanism and can drive the processing module to rotate relative to the cylinder under the action of the driving mechanism to process the material;

[0012] The twin-screw extruder is divided into six processing sections along the conveying direction of the material, namely, a feeding section, a conveying section, a mixing section, a cooking section, a melting section and a transfer section, and the feed port is correspondingly arranged in the feeding section;

[0013] Among them, the feeding section and the transfer section are both equipped with a forward conveying module, the conveying section is equipped with a forward conveying module, a forward meshing module and a pressure ring, the mixing section is equipped with a forward conveying module, a forward meshing module and a reverse meshing module, the cooking section is equipped with a forward conveying module, a forward meshing module, a reverse meshing module and a reverse conveying module, and the melting section is equipped with a forward conveying module, a pressure ring and a reverse conveying module.

[0014] In addition, an optional solution is that the pressure ring, the positive engagement module and the positive conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the conveying section.

[0015] In addition, an optional solution is that the melting section includes a forward meshing module, a forward conveying module, a pressure ring and a reverse conveying module, and the forward conveying module, the pressure ring, the forward meshing module and the reverse conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the melting section.

[0016] In addition, an optional solution is that the forward conveying module, the forward meshing module and the reverse meshing module are sequentially arranged on the core shaft along the conveying direction of the material in the mixing section;

[0017] The forward conveying module, the forward meshing module, the reverse meshing module and the reverse conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the cooking section.

[0018] In addition, an optional solution is that, in the conveying section or the melting section, the pressure rings are arranged in pairs on the two core shafts;

[0019] The pressure ring comprises a first structure portion and a second structure portion sequentially arranged along the axial direction of the core shaft, the first structure portion and the second structure portion are coaxially arranged, and the outer diameter of the second structure portion is greater than the outer diameter of the first structure portion;

[0020] The second structural portion of the pressure ring on one of the mandrels is located in front of the first structural portion in the material conveying direction, and the second structural portion of the pressure ring on the other mandrel is located behind the first structural portion in the material conveying direction, and the pressure rings on the two mandrels are meshed with each other.

[0021] In addition, an optional solution is that the second structural portion of the pressure ring located in the conveying section is provided with an overflow groove, and the overflow grooves of the pressure rings respectively located on the two core shafts do not completely overlap during the rotation of the core shafts.

[0022] In addition, an optional solution is that the pressure ring includes three overflow grooves, and the three overflow grooves are evenly distributed on the circumference of the second structural part.

[0023] In addition, an optional solution is that the overflow trough is arranged obliquely, and its inclination direction is the same as the rotation direction of the forward conveying module.

[0024] In addition, an optional solution is that the twin-screw extruder further includes a solid feeder, and the discharge port of the solid feeder faces the feed port of the barrel to provide whole seed grain material.

[0025] According to another aspect of the utility model, there is provided a grain processing device, comprising:

[0026] Flexible peeling device for soft and gentle crushing and cleaning of grains;

[0027] A hot steam treatment device for steam-inactivating enzymes in grains;

[0028] A wheat tempering device is used to temper the grains;

[0029] Twin-screw extruders for texturizing grains;

[0030] The buffer drying device is used to dry the extruded texturized material.

[0031] The beneficial effects of the utility model are as follows:

[0032] The embodiment of the utility model provides a twin-screw extruder and grain processing equipment, in which each functional module is configured on the core shaft corresponding to each processing section according to the function of each processing section, and is used for the extrusion processing of whole grain grains and grain bran. Specifically, a pressure ring is added to the conveying section and the melting section to increase the pressure in the cylinder and enhance the degree of melting and reorganization of each component of the grain to adapt to the direct extrusion processing of whole grain grains and improve the fineness, flavor and stability of high-fiber grain texturized materials. In the conveying section, the pressure ring replaces part of the forward conveying module and the forward meshing module, which not only helps to mix the materials, but also drives the materials to flow forward faster, strengthens the degree of damage to the fiber structure of the whole grain material, and makes the extruded tissue structure obtained by processing uniform and consistent. In addition, the pressure ring is set at one end of the conveying section close to the feeding section, which can prevent backflow and increase the pressure of the forward meshing module on the material, thereby achieving a better shearing effect. In the melting section, the pressure ring replaces part of the forward meshing module to mix and shear the materials, and can also push the materials to flow forward faster, which can increase the flow rate of the materials in the melting section, avoid the problem of unpleasant puffed paste taste of the extruded structured materials caused by excessive gelatinization and caramelization of grain starch at high temperature, and improve the fineness, flavor, color and stability of the structured materials after grain processing. The extrusion of high-fiber grain whole kernels is realized, and stable extruded structured materials with rich nutty flavor and delicate taste are obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings.

[0034] Figure 1 The schematic diagram of the structure of the twin-screw extruder provided by the embodiment of the utility model is shown.

[0035] Figure 2 A schematic structural diagram of each processing section provided in an embodiment of the utility model is shown.

[0036] Figure 3 A schematic structural diagram showing the working module provided by an embodiment of the utility model is installed on the core shaft.

[0037] Figure 4 A schematic structural diagram of a forward conveying module provided in an embodiment of the utility model is shown.

[0038] Figure 5 A schematic structural diagram of a reverse conveying module provided in an embodiment of the utility model is shown.

[0039] Figure 6 A schematic structural diagram of a forward meshing module provided in an embodiment of the utility model is shown.

[0040] Figure 7A schematic structural diagram of a reverse engagement module provided in an embodiment of the utility model is shown.

[0041] Figure 8 An axial view showing a structural form of a positive engagement module provided by an embodiment of the utility model.

[0042] Fig. 9 An axial view showing another structural form of the positive engagement module provided in an embodiment of the utility model.

[0043] Fig.10 An axial view of the reverse engagement module provided by the embodiment of the present utility model is shown.

[0044] Fig.11 A schematic structural diagram of a pressure ring located in a conveying section provided by an embodiment of the utility model is shown.

[0045] Fig.12 A schematic structural diagram of a pressure ring located in the melting section provided by an embodiment of the utility model is shown.

[0046] Fig.13 The physical pictures of the extruded materials of Example 1 and Comparative Example 4 are shown.

[0047] Fig.14 Schematic diagrams of the microstructures of the extruded materials of Example 1 and Comparative Example 4 are shown.

[0048] Fig.15 A schematic diagram showing the microstructure of oat milk produced from the extruded material of Example 1. DETAILED DESCRIPTION

[0049] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0050] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In the present invention, unless otherwise clearly stipulated and limited, the first feature being "on" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them.

[0052] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0053] High-fiber cereals usually refer to cereal grains, including the germ and cortex. In order to retain its nutritional value, the whole grain is usually crushed during the flour processing. However, during the flour grinding process, the grain's own biological enzymes are activated, and on the other hand, the grains are rich in unsaturated fatty acids and are exposed to oxygen during the flour grinding process. Under the combined action of high temperature, oxygen and highly active enzymes, oxidation and rancidity easily occur, causing quality deterioration.

[0054] At present, extrusion puffing technology is generally used to process grains. Usually, the grains are crushed to a certain fineness and then fed into the extruder. However, under the action of high temperature, high pressure and high shear force of the extruder, the starch is further degraded after gelatinization, and the Maillard reaction occurs with the exposed amino groups, producing a puffed paste taste, which will affect the flavor quality of the final product and reduce the product acceptability. In addition, due to the tough texture of the grain bran, the processed grain bran has a strong bran taste and a rough texture due to the limitations of the process and equipment, which cannot meet the requirements of creative food.

[0055] In view of the defects of the prior art, the present invention provides a twin-screw extruder, Figure 1-15 As shown, the twin-screw extruder includes a barrel 1, two core shafts 2 arranged in parallel in the barrel 1, a processing module sleeved on the core shaft 2, and a driving mechanism (not shown). The barrel 1 includes a feed port 10, and the material to be processed enters the barrel 1 through the feed port 10 for subsequent processing. The two core shafts 2 are arranged in parallel in the barrel 1, and the core shafts 2 are extended along the axial direction of the barrel 1. The output end of the driving mechanism is fixedly combined with the core shaft 2, and the core shaft 2 can drive the processing module to rotate in the barrel 1 under the action of the driving mechanism to process the material entering the barrel 1 through the feed port 10.

[0056] The twin-screw extruder can be a co-directional meshing type, a counter-directional meshing type or a non-meshing type. In this embodiment, the co-directional meshing type is used for illustration. The speed of the output end of the drive mechanism can be a fixed speed or a variable speed. In this embodiment, a variable speed drive mechanism is used to meet different usage requirements. More specifically, during the grain processing, the speed of the twin-screw extruder is between 150r / min and 300r / min.

[0057] In one embodiment, the processing module includes a forward conveying module 31, a reverse conveying module 32, a forward meshing module 33, a reverse meshing module 34 and a pressure ring 35. The twin-screw extruder is divided into six processing sections along the conveying direction of the material, namely, a feeding section 41, a conveying section 42, a mixing section 43, a cooking section 44, a melting section 45 and a transfer section 46. The forward conveying module 31, the reverse conveying module 32, the forward meshing module 33, the reverse meshing module 34 and the pressure ring 35 are arranged on the core shaft 2 corresponding to each processing section according to the function of each processing section, and different processing sections are provided with processing modules of different sizes, types and numbers according to different functions.

[0058] The outer surface of the core shaft 2 is provided with grooves or external splines, and the inner wall surface of each processing module is provided with a key corresponding to the grooves or external splines, so that each processing module can be sleeved on the core shaft 2.

[0059] In an optional embodiment, the diameter of the core shaft 2 is 39 mm to 65 mm, and the ratio of length to diameter is 23:1 to 37:1. Specifically, the diameter of the core shaft 2 is 65 mm, and the ratio of length to diameter is 37:1.

[0060] Specifically, Figure 1 As shown, the feed port 10 is correspondingly arranged at the feeding section 41, which is used to convey the whole grain material into the cylinder 1. The function of the feeding section 41 is to feed the whole grain material into the conveying section 42; the function of the conveying section 42 is to preliminarily crush the whole grain material and push it forward, or to stir the powdered material and push the powdered material forward; the function of the mixing section 43 is to further crush the preliminarily crushed material or to mix the powdered material with liquids such as water; the function of the cooking section 44 is to heat, cook and shear the paste material; the function of the melting section 45 is to further heat and crush the molten material; the function of the transfer section 46 is to convey the molten material to the end of the cylinder 1 and transfer it to the next process.

[0061] In a specific embodiment, a forward conveying module 31 is sleeved on the core shaft 2 corresponding to each processing section. Figure 4As shown, the forward conveying module 31 adopts a threaded module, and the forward conveying modules 31 sleeved on the two core shafts 2 are arranged in pairs, and the conveying direction of the forward conveying module 31 is consistent with the extrusion direction of the material. The material can move along the screw groove of the threaded module with the rotation of the core shaft 2 to achieve the conveying and mixing of the material. The forward conveying module 31 can be a single-start screw groove, a double-start screw groove, or a triple-start screw groove, and different pitches can be used according to needs to change the moving speed of the material in the corresponding processing section.

[0062] In this embodiment, if Figure 3 As shown, in the conveying section 42, according to its function, in addition to the forward conveying module 31, a forward meshing module 33 and a pressure ring 35 are also configured; in the mixing section 43, according to its function, in addition to the forward conveying module 31, a forward meshing module 33 and a reverse meshing module 34 are also configured; in the cooking section, according to its function, in addition to the forward conveying module 31, a reverse conveying module 32, a forward meshing module 33 and a reverse meshing module 34 are also configured; in the melting section, according to its function, in addition to the forward conveying module 31, a reverse conveying module 32 and a pressure ring 35 are also configured.

[0063] like Figure 5 As shown, the reverse conveying module 32 adopts a threaded module, and the reverse conveying modules 32 sleeved on the two core shafts 2 are arranged in pairs, but the conveying direction of the reverse conveying module 32 is opposite to the extrusion direction of the material. As a resistance module, it hinders the conveying of the material, and is used to form a seal and establish high pressure. The reverse conveying module 32 is arranged in the cooking section 44 and the melting section 45 to increase the residence time of the material in the processing section. In the cooking section 44, it helps to ensure that the material obtains sufficient processing time and heat transfer during the cooking process, and achieves a more uniform cooking effect, which is particularly important for materials that need to reach a specific cooking degree or retain specific nutrients. In the melting section 45, it can increase the melting time and mixing effect of the material, so that the material will be subjected to stronger shearing and mixing in the melting area, thereby accelerating the melting process of the material and improving the uniformity and quality of the melting. Specifically, the reverse conveying module 32 can be a single-start thread groove, a double-start thread groove or a triple-start thread groove, and different leads can be used according to needs to achieve the resistance effect in the corresponding processing section.

[0064] like Figure 6-10 As shown, the forward meshing module 33 and the reverse meshing module 34 are both formed by staggered splicing of a plurality of sheet-shaped meshing blocks or shear blocks, and the staggered angles include 30°, 45°, 60° and 90°. Figure 8 The engagement block 330 shown may include two engagement portions arranged symmetrically to the center, such as Fig. 9As shown, the meshing block 330 may also include only a single-sided meshing portion. Those skilled in the art may select according to their needs. Both the forward meshing module 33 and the reverse meshing module 34 are applicable. The difference between the forward meshing module 33 and the reverse meshing module 34 is that the meshing block 330 is installed in opposite directions. The forward meshing element 33 is mainly used for mixing and shearing of materials, and also has conveying capacity. The reverse meshing element 34 mainly acts as a drag flow, increases back pressure, and increases the circulation flow of materials in the high shear zone, thereby achieving the purpose of strong dispersion and mixing.

[0065] In a specific embodiment, Figure 3 As shown, in the conveying section 42, the pressure ring 35, the forward meshing module 33 and the forward conveying module 31 are sequentially arranged on the core shaft 2 along the conveying direction of the material. The role of the pressure ring 35 at the conveying section 42 is to replace part of the forward conveying module 31, and convey the material transferred from the feeding section 41 to the forward meshing module 33 for mixing and shearing the material, and to perform preliminary crushing on the material. The pressure ring 35 is arranged on the side of the conveying section 42 close to the feeding section 41, and replaces the forward conveying module 31 to convey the material, and can also replace the forward meshing module 33 to mix and shear the material. When the material passes through the pressure ring 35, due to the presence of the ring, the material is compressed and sheared, thereby increasing the density and compactness of the material. This compression effect not only helps the mixing of the material, but also can push the material to flow forward faster, and strengthen the degree of damage to the fiber structure of the whole grain material, so as to adapt to the direct extrusion processing of the whole grain of cereals, so that the extruded tissue structure obtained by the processing is uniform. In addition, the pressure ring 35 is arranged at one end of the conveying section 42 close to the feeding section 41, which can prevent backflow and increase the pressure of the forward meshing module 33 on the material, thereby achieving a better shearing effect.

[0066] Compared with the existing twin-screw extruders, since the existing twin-screw extruders are mostly used to prepare plant protein meat, meat paste or plastic products, the hardness of their principles is lower than that of whole grain cereals. Therefore, during the extrusion process, the resistance encountered by the material is smaller than that of the whole grain cereals, so the risk of backflow in the conveying section 42 is relatively small; the twin-screw extruder provided in the present application is used to extrude whole grain cereals. In order to ensure the fine and uniform processing effect of the cereals, it is necessary to set a pressure ring 35 in the conveying section 42 to increase the flow rate of the material and the crushing effect of the material, while preventing the backflow of the material and increasing the pressure of the forward meshing module 33 on the material, so that the extruded tissue structure obtained is uniform.

[0067] In this embodiment, if Figure 2-3As shown, an overflow groove 350 is provided on the pressure ring 35 located in the conveying section 42. The overflow groove 350 provides an additional flow channel for the material during the extrusion process. When the material is compressed by the pressure ring 35, part of the material will flow through the overflow groove 350 located on the pressure ring 35 to the forward meshing module 33, thereby reducing the pressure accumulation of the material during the conveying process, which is beneficial to releasing the resistance of the material during the conveying process, allowing the material to move more smoothly and increasing the flow rate of the material.

[0068] The pressure rings 35 are arranged in pairs on the two mandrels 2 and mesh with each other. The overflow grooves 350 of the pressure rings 35 respectively located on the two mandrels 2 do not completely overlap during the rotation of the mandrels.

[0069] In a specific embodiment, Figure 3 As shown, in the melting section 45, the forward conveying module 31, the pressure ring 35 and the reverse conveying module 34 are sequentially arranged on the core shaft 2 along the conveying direction of the material. The role of the pressure ring 35 in the melting section 45 is to replace at least part of the forward meshing module 33 to mix and shear the material. The material is mainly further heated and further crushed in the melting section 45. In this embodiment, the melting section 45 is not provided with a forward meshing module 33, and the pressure ring 35 replaces the forward meshing module 33 to further crush the material. When the material passes through the pressure ring 35, due to the presence of the pressure ring 35, the material is compressed and sheared. This compression not only helps the mixing of the material, but also drives the material to flow forward faster. The shearing action further destroys the limiting structure of the grain, making the extruded organized material more delicate.

[0070] Since the structure of the pressure ring 35 is simpler than that of the forward meshing module 33 and has a shorter stroke, it also has the function of promoting the rapid flow of materials. By replacing the forward meshing module 33 with the pressure ring 35 to further shear the material, the flow rate of the material in the melting section 45 can be increased, and the problem of unpleasant puffed paste taste of the extruded texturized material caused by excessive gelatinization and caramelization of grain starch under high temperature can be avoided, thereby improving the fineness, flavor, color and stability of the texturized material after grain processing.

[0071] The existing twin-screw extruder generally has two groups of forward meshing dies 33 in the melting section 35. In one embodiment, a pressure ring 35 is used to replace a group of forward meshing modules 33 in the melting section 35, that is, the melting section 35 includes a forward meshing module 33, a forward conveying module 31, a pressure ring 35 and a reverse conveying module 32, and the forward meshing module 33, the forward conveying module 31, the pressure ring 35 and the reverse conveying module 32 are sequentially arranged on the core shaft 2 in the order of the forward conveying module 31, the pressure ring 35, the forward meshing module 33 and the reverse conveying module 32 in the conveying direction of the material. When the material passes through the pressure ring 35, due to the existence of the pressure ring 35, the material is compressed and sheared. This compression not only helps the mixing of the material, but also can push the material to flow forward faster, and this shearing action further destroys the limiting structure of the grain. At the same time, the shearing of the material by the forward meshing module 33 makes the extruded structured material more delicate. The pressure ring 35 promotes the rapid movement of the material. Compared with the original design of two sets of positive meshing modules 33, the design of the pressure ring 35 plus a set of positive meshing modules 33 not only shortens the material movement distance, but also increases the flow rate of the material, shortens the time the material stays in the melting section 35, avoids the problem of unpleasant puffed paste taste of the extruded texturized material caused by excessive gelatinization and caramelization of grain starch under high temperature, and improves the fineness, flavor, color and stability of the texturized material after grain processing.

[0072] In a specific embodiment, in the mixing section 43, the forward conveying module 31, the forward meshing module 33 and the reverse meshing module 34 are sequentially arranged on the core shaft 2 along the conveying direction of the material. The reverse meshing module 34 is arranged in the mixing section 43 to increase the back pressure and increase the circulation of the material in the forward meshing module 33, so as to achieve the purpose of strong dispersion and mixing, so that the material can be fully crushed and mixed.

[0073] In the cooking section 44, the forward conveying module 31, the forward meshing module 33, the reverse meshing module 34 and the reverse conveying module 35 are sequentially arranged on the core shaft 2 along the conveying direction of the material. The reverse meshing module 34 is arranged in the cooking section 44 to increase the back pressure and increase the circulation of the material in the forward meshing module 33, so as to achieve the purpose of strong dispersion and mixing, so that the material can be fully crushed, mixed and heated. The reverse conveying module 32 is arranged in the cooking section 44 to hinder the transportation of the material, to form a seal and establish high pressure, to increase the residence time of the material in the cooking section 44, to help ensure that the material obtains sufficient processing time and heat transfer during the cooking process, and to achieve a more uniform cooking effect, which is particularly important for materials that need to reach a specific cooking degree or retain specific nutrients.

[0074] In one embodiment, in the conveying section 42 and the melting section 45, the pressure rings 35 are arranged in pairs on the two mandrels 2. Specifically, the pressure rings include a first structure portion 351 and a second structure portion 352 arranged in sequence along the axial direction of the mandrel 2, the first structure portion 351 and the second structure portion 352 are arranged coaxially, and the outer diameter of the second structure portion 352 is greater than the outer diameter of the first structure portion 351. The second structure portion 352 of the pressure ring 35 on one mandrel 2 is located in front of the first structure portion 351 in the conveying direction of the material, and the second structure portion 352 of the pressure ring 35 on the other mandrel is located behind the first structure portion 351 in the conveying direction of the material, that is, the second structure portion 352 of one pressure ring 35 is arranged corresponding to the first structure portion 351 of the other pressure ring 35, so that the pressure rings 35 on the two mandrels 2 are meshed with each other, so that during the rotation of the two mandrels 2, due to the meshing relationship between the two pressure rings 35, the material is subjected to shear force and driving force, which can not only shear and mix the material, but also promote the rapid flow of the material.

[0075] In this embodiment, the overflow groove 350 is formed in the second structure portion 352 , and the overflow groove 350 is only formed on the pressure ring 35 located in the conveying section 42 .

[0076] Three overflow grooves 350 are formed on the pressure ring 35 located in the conveying section 42 . The three overflow grooves 350 are evenly distributed around the second structure portion 352 .

[0077] In one embodiment, the overflow trough 350 is disposed obliquely, and its inclination direction is the same as the rotation direction of the forward conveying module 33, which can promote the flow of materials in the same direction.

[0078] In one embodiment, the twin-screw extruder further includes a solid feeder 5, the discharge port of the solid feeder 5 is toward the feed port 10 of the barrel 1, so as to provide whole seed grain materials. The solid feeder 5 can be a horizontal screw feeder, including a drive motor, a housing and a screw shaft, and the housing is provided with a loading port and a discharge port, and the screw shaft is driven by the drive motor to rotate, thereby conveying the material. The number of screw shafts can be one or more, and in this embodiment, two screw shafts are used as an example for explanation. The use of a double-shaft solid feeder 5 to convey whole seed grain materials can ensure uniform mixing of multiple raw materials, while avoiding material agglomeration and ensuring the efficiency of material conveying.

[0079] The advantages of the twin-screw extruder provided by the embodiment of the utility model are described below by comparative examples:

[0080] Embodiment 1:

[0081] The twin-screw extruder provided by the embodiment of the utility model, wherein the conveying section 42 includes a pressure ring 35, a forward meshing module 33 and a forward conveying module 31, and the melting section 45 includes a forward conveying module 31, a pressure ring 35 and a reverse conveying module 32. The pressure ring 35 located in the conveying section 42 is provided with an overflow groove 350. Each working module is mounted on the mandrel 2 and placed in the barrel 1, and connected with a die head with an 8mm die hole. The temperature of different processing sections of the twin-screw extruder is set for preheating. The whole grain oats are treated with water (3.5% water by weight of oats), stirred with water for 2.5 minutes, fed into the solid feeder, and the twin-screw extruder is started. The organization of the oats is completed during the extrusion process to obtain the oat extrusion organization material. Specific operating parameters: extrusion temperature 170-190°C, screw speed 275r / min, material flow rate of the solid feeder 120kg / h. The properties of the prepared oat extruded texturized material are as follows: white in color, without oat grains, low hardness, uniform structure, and rich cereal aroma and nutty flavor.

[0082] Comparative Example 1:

[0083] Compared with Example 1, the pressure ring 35 located at the conveying section 42 and the melting section 45 is provided with an overflow groove 350, and the remaining structures and processing conditions are the same as those of Example 1. The properties of the prepared oat extruded texturized material are compared with those of Example 1: the color is yellow-brown, the color of the oat grain part is similar to that of the part without oat grains, it has a light cereal aroma, no flavor such as nuts, and the oat grains are more obvious.

[0084] Comparative Example 2:

[0085] Compared with Example 1, each processing section is not provided with a positive meshing module 33, and the remaining structures and processing conditions are the same as those of Example 1. The properties of the prepared oat extruded texturized material are compared with those of Example 1: the color is dark, yellow-brown, and uneven, mixed with white oat grains, presents an oat bran flavor, has no nut flavor, and has more oat grains.

[0086] Comparative Example 3:

[0087] Compared with Example 1, the melting section 45 includes a forward conveying module 31, a pressure ring 35, a forward meshing module 33 and a reverse conveying module 32, and the remaining structures and processing conditions are the same as those of Example 1. The properties of the prepared oat extruded texturized material are compared with those of Example 1: the color is light yellow-brown, the flavor is rich in cereal and nut flavor, and no oat grains are present.

[0088] Comparative Example 4:

[0089] After the whole oat kernels are crushed, a conventional twin-screw extruder without a meshing module and a pressure ring is used, and the extrusion temperature is set at 170-180°C, the screw speed is set at 275r / min, and the material flow rate of the solid feeder is set at 160kg / h to obtain an extruded expanded material.

[0090] The material pictures obtained in Example 1 and Comparative Example 4 are as follows: Fig.13 As shown. It can be seen that the left side is the extrusion material obtained in comparative example 4, which is columnar, thin, and has a honeycomb structure, poor color uniformity, and is yellowish brown. The right side is the extrusion material obtained in Example 1, which is columnar, thick, white in color, and has a uniform structure without a honeycomb structure.

[0091] Comparing the microstructures of the extruded materials of Example 1 and Comparative Example 4, the microstructures were observed at 3000 times magnification. Fig.14 As shown. The left side is the microstructure diagram of the extrudate obtained in comparative example 4. From the diagram, it can be seen that the starch is gelatinized, a small amount of starch particles still exist, and the structure is dense; the right side is the microstructure diagram of the extrudate obtained in Example 1. From the diagram, it can be seen that the microstructure of the extrudate shows holes, loose structure, and small particles. It can be seen that the grain fiber structure processed by the twin-screw extruder provided by the embodiment of the utility model has holes, loose structure, small particles, and a large degree of starch degradation, which improves the processing suitability of oat bran.

[0092] The extruded materials obtained in Example 1 and Comparative Example 4 were respectively used to prepare oat milk, and the specific steps were as follows: cooking, pumping in hot water (above 90° C.) 2-3 times the weight of the texturized material, stirring and steaming for 5 minutes; adding room temperature water 1-2 times the weight of the texturized material to cool down, adding liquefying enzyme 1-2‰ of the texturized material after mixing, and feeding the grinding equipment after beating evenly, and wet grinding using two-stage refining, the aperture of the first-stage screen plate is 0.18-0.25 mm, and the aperture of the second-stage wet grinding screen plate is 0.04-0.08 mm; pumping in In the enzymolysis tank, heat to 60-65°C, add 1%-2% alpha-amylase by weight of whole grain oats, add 0.09%-0.18% amyloglucosidase by weight of whole grain oats after enzymolysis for 10-15 minutes, enzymolysis for 40-45 minutes, heat to 90-95°C, inactivate enzyme for 5-15 minutes; pump into low-pressure jet mill, set pressure to 40-60MPa, further pump into high-pressure jet mill, pressure is 80MPa-150MPa; preferably 100MPa-130MPa. Finally, mix, homogenize and sterilize to obtain whole grain oat milk.

[0093] The sensory evaluation of whole grain oat milk prepared by different processing methods showed that the oat milk prepared by the extrusion material of comparative example 4 had a strong puffed paste flavor, while the oat milk prepared by the extrusion material of example 1 had a strong grain flavor, nut flavor, and sweet flavor, no raw oat flavor and puffed paste flavor, smooth taste, and smaller particle size. It can be seen that the twin-screw extruder provided by the embodiment of the utility model is better than the traditional twin-screw extruder in processing oats.

[0094] Furthermore, the microstructure of the oat milk obtained from the extruded material of Example 1 was observed. The whole grain oat milk was freeze-dried using a freeze dryer, and the microstructure of the whole grain oat milk was observed using a scanning electron microscope. Fig.15 It can be seen that the whole grain oat milk is full of spherical or irregular shaped particles, and the particle diameter is small, indicating that the whole grain oat milk prepared by the texturized material obtained by the twin-screw extruder provided in the embodiment of the utility model is more delicate.

[0095] Furthermore, the stability of the oat milk obtained from the extruded material of Example 1 was compared with the stability of commercially available oat milk. The instability index was determined using a stability analyzer, the prepared sample was shaken evenly, a quantitative sample was accurately weighed, and added to the sample tank. The measurement parameters were set as follows: centrifugation at a speed of 4000 rpm for 1 hour at a temperature of 25°C, scanning every 10 seconds, and the instrument automatically recorded the scanning results. The instability index refers to the change in light transmittance of each part of the sample over time during the centrifugation process. The smaller the instability index, the less likely the sample is to be stratified and has better stability. The experimental results show that the instability coefficient of commercially available oat milk is 0.578, and the instability coefficient of oat milk obtained from the extruded material of Example 1 is 0.426. According to the experimental results, the instability index of the oat milk obtained from the extruded material of Example 1 is significantly lower than that of commercially available oat milk, indicating that the whole grain oat milk prepared from the organized material prepared by the twin-screw extruder provided in the embodiment of the utility model has good stability.

[0096] According to the comparison results of the above-mentioned comparative examples with Example 1, it can be seen that the extruded texturized material produced by the twin-screw extruder provided by the embodiment of the utility model has a bright color, a large degree of starch degradation, a low degree of starch gelatinization, no puffed paste smell, a smooth taste, and a smaller particle size.

[0097] Another embodiment of the utility model provides a grain processing equipment, including a flexible peeling device for flexibly lightly grinding and cleaning grains; a hot steam treatment device for steam-inactivating enzymes in grains; a wheat tempering device for tempering grains; a twin-screw extruder for extruding and texturizing grains; a buffer drying device for drying the extruded texturized material; and a storage tank for storing the obtained extruded texturized material.

[0098] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A twin-screw extruder, characterized in that: include: A cylinder, the cylinder comprising a feed inlet; Two core shafts are arranged in parallel in the cylinder, and the core shafts are extended along the axial direction of the cylinder; a processing module sleeved on the mandrel, the processing module comprising a forward conveying module, a reverse conveying module, a forward meshing module, a reverse meshing module and a pressure ring; and A driving mechanism, wherein the core shaft is fixedly coupled to an output end of the driving mechanism and can drive the processing module to rotate relative to the cylinder under the action of the driving mechanism to process the material; The twin-screw extruder is divided into six processing sections along the conveying direction of the material, namely, a feeding section, a conveying section, a mixing section, a cooking section, a melting section and a transfer section, and the feed port is correspondingly arranged in the feeding section; Among them, the feeding section and the transfer section are both equipped with a forward conveying module, the conveying section is equipped with a forward conveying module, a forward meshing module and a pressure ring, the mixing section is equipped with a forward conveying module, a forward meshing module and a reverse meshing module, the cooking section is equipped with a forward conveying module, a forward meshing module, a reverse meshing module and a reverse conveying module, and the melting section is equipped with a forward conveying module, a pressure ring and a reverse conveying module.

2. The twin-screw extruder according to claim 1, characterized in that The pressure ring, the positive engagement module and the positive conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the conveying section.

3. The twin-screw extruder according to claim 1, characterized in that The melting section comprises a forward meshing module, a forward conveying module, a pressure ring and a reverse conveying module, wherein the forward conveying module, the pressure ring, the forward meshing module and the reverse conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the melting section.

4. The twin-screw extruder according to claim 1, characterized in that The forward conveying module, the forward meshing module and the reverse meshing module are sequentially arranged on the core shaft along the conveying direction of the material in the mixing section; The forward conveying module, the forward meshing module, the reverse meshing module and the reverse conveying module are sequentially arranged on the core shaft along the conveying direction of the material in the cooking section.

5. The twin-screw extruder according to claim 1, characterized in that In the conveying section or the melting section, the pressure rings are arranged in pairs on the two core shafts; The pressure ring comprises a first structure portion and a second structure portion sequentially arranged along the axial direction of the core shaft, the first structure portion and the second structure portion are coaxially arranged, and the outer diameter of the second structure portion is greater than the outer diameter of the first structure portion; The second structural portion of the pressure ring on one of the mandrels is located in front of the first structural portion in the material conveying direction, and the second structural portion of the pressure ring on the other mandrel is located behind the first structural portion in the material conveying direction, and the pressure rings on the two mandrels are meshed with each other.

6. The twin-screw extruder according to claim 5, characterized in that The second structural part of the pressure ring located in the conveying section is provided with an overflow groove, and the overflow grooves of the pressure rings respectively located on the two core shafts do not completely overlap during the rotation of the core shafts.

7. The twin-screw extruder according to claim 6, characterized in that The pressure ring includes three overflow grooves, and the three overflow grooves are evenly distributed on the circumference of the second structural part.

8. The twin-screw extruder according to claim 6, characterized in that The overflow trough is arranged obliquely, and its inclination direction is the same as the rotation direction of the forward conveying module.

9. The twin-screw extruder according to claim 1, characterized in that The twin-screw extruder further comprises a solid feeder, wherein the discharge port of the solid feeder faces the feed port of the barrel to provide whole seed grain materials.

10. A grain processing device, characterized in that: include: Flexible peeling device for soft and gentle crushing and cleaning of grains; A hot steam treatment device for steam-inactivating enzymes in grains; A wheat tempering device is used to temper the grains; A twin-screw extruder as claimed in any one of claims 1 to 9, used for extrusion texturization of grains; The buffer drying device is used to dry the extruded texturized material.

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