A soybean dietary fiber purification system and purification process

Abstract

A soybean dietary fiber purification system and purification process, the purification system includes a high-pressure plunger pump, a convergent nozzle, a crushing tank, a mixing tank, a swelling tank, a pipeline mixer and an ion exchange tank, and the purification process includes mechanical crushing, mechanical filtration, primary mixing, swelling, secondary mixing, complexation and post-treatment. The present invention relies on the coordination of the system and the process to effectively remove the residual protein and metal ions in the soybean dietary fiber, so as to achieve the purpose of purifying the soybean dietary fiber. The prepared fiber product is of the same quality as the fiber product imported from abroad, and can meet the standard of domestic substitution.

Description

Technical Field

[0001] The invention relates to the technical field of soybean dietary fiber processing, in particular to a soybean dietary fiber purification system and a purification process. Background Art

[0002] Soybean dietary fiber is a high-quality fiber source with abundant domestic resources. However, due to technical reasons, the soybean dietary fiber products currently produced in China are mixed with a large amount of non-fiber "impurities". The content of pure soybean dietary fiber can only reach more than 50% at most. These "impurities" mainly include about 20% crude protein and about 20% glucose, oligosaccharides and metal ions such as calcium, magnesium, sodium and potassium. As a result, the purity of soybean dietary fiber currently produced in China is not enough and it can only be used as ordinary dietary fiber raw material. Most of it is used in animal feed, and a small part is used as food raw materials after sterilization, crushing and other primary processing. However, some industries that have special requirements for the purity of dietary fiber, such as the pharmaceutical industry, functional food raw materials, nutritional supplement raw materials and other fields, currently rely on imports for their dietary fiber sources.

[0003] The main reason why the purity of domestic soybean dietary fiber is not high is that the soybean protein, calcium, magnesium and other metal ions carried in soybean dietary fiber cannot be effectively controlled, which is the main reason restricting the application of domestic soybean dietary fiber in the high-end market. Among them, the residue of soybean protein in the fiber is mainly limited by the soybean protein extraction process, and the residual content accounts for 16-25% of soybean fiber, including high-polymerization 15S protein and glycoprotein combined with carbohydrates that remain in soybean dietary fiber due to extraction and separation. The residue of metal ions such as calcium and magnesium is due to the molecular bonding of soybean dietary fiber, which makes metal ions such as calcium and magnesium "wrapped and buried" and cannot be effectively removed by ion exchange. The above is the core key to the current problem of the low purity of soybean dietary fiber. How to effectively remove the residual protein and metal ions in soybean dietary fiber and prepare high-purity soybean dietary fiber to break the current situation of product dependence on foreign imports has become an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a soybean dietary fiber purification system and purification process. Relying on the cooperation of the system and the process, the residual protein and metal ions in the soybean dietary fiber can be effectively removed to achieve the purpose of purifying the soybean dietary fiber. The prepared fiber product is of the same quality as the fiber products imported from abroad and can meet the standards for domestic substitution.

[0005] The technical solutions adopted by the present invention to solve the above problems are as follows:

[0006] A soybean dietary fiber purification system comprises a high-pressure plunger pump, a convergent-divergent nozzle, a crushing tank, a mixing tank, a swelling tank, a pipeline mixer and an ion exchange tank, wherein the outlet of the high-pressure plunger pump is connected to the inlet of the convergent-divergent nozzle through a pipeline, the outlet of the convergent-divergent nozzle is connected to the inlet of one side of the crushing tank, a conical wire-wound filter screen is arranged in the crushing tank, the tip of the conical wire-wound filter screen is horizontally placed in the outlet pipe mouth of the convergent-divergent nozzle, the large-diameter open end of the conical wire-wound filter screen is connected to the inlet of one side of the mixing tank, a stirring mechanism is arranged in the mixing tank, the bottom outlet of the mixing tank is connected to the bottom inlet of the swelling tank through a feeding pipeline and a feeding pump, the top outlet of the swelling tank is connected to the pipeline mixer through a pipeline, the outlet of the pipeline mixer is connected to the bottom inlet of the ion exchange tank through a pipeline, and a discharge port is arranged on the top of the ion exchange tank.

[0007] As a preferred embodiment of the above technical solution, the outer circumference of the swelling tank is provided with a heating sleeve with sealed ends, the cavity between the heating sleeve and the swelling tank is a steam heating cavity, and a steam inlet is provided on one side of the heating sleeve.

[0008] As a preferred solution of the above technical solution, the conical wire-wound filter is formed by winding a metal wire along a cone structure, and the gap between any two adjacent circles of the metal wire is the filtering gap.

[0009] As a preferred solution of the above technical solution, the vertical cross-section of the metal wire is a trapezoidal structure, and the filtering gap is 15-50 microns.

[0010] As a preferred solution of the above technical solution, a reflux pipe connected to the high-pressure plunger pump is provided at the bottom of the crushing tank.

[0011] As a preferred embodiment of the above technical solution, the crushing tank and the mixing tank are of a square joint structure.

[0012] A soybean dietary fiber purification process comprises the following steps:

[0013] Step 1: Mechanical crushing:

[0014] The material is sent into the convergent-divergent nozzle through a high-pressure plunger pump, and is accelerated by the convergent-divergent nozzle to impact on the conical wire-wrapped filter in the crushing tank to complete mechanical crushing. At the same time, hemicellulose solvent is added to the crushing tank during the crushing process.

[0015] Wherein, the material is a soybean dietary fiber solution obtained by mixing soybean dietary fiber powder and distilled water in a weight ratio of 1:20-25;

[0016] Step 2, mechanical filtration:

[0017] The mechanically crushed materials pass through the filter gap on the conical wire mesh and enter the inner cavity of the conical wire mesh, and naturally flow into the mixing tank. The uncrushed or incompletely crushed materials are re-sent to the high-pressure plunger pump through the return pipe at the bottom of the crushing tank.

[0018] Step 3, one-time mixing:

[0019] Adding ammonium ions into the mixing tank to fully stir and mix them with the materials entering the mixing tank;

[0020] The amount of ammonium ions added is 0.1-0.3% of the total weight of the crushed material, and the pH value of the mixed material in the mixing tank is controlled at 8-9;

[0021] Step 4: Swelling:

[0022] Steam is introduced into the heating sleeve to keep the temperature in the swelling tank at 75-90 degrees Celsius, and then the mixture obtained in step 3 is pressed into the swelling tank in a plug flow manner;

[0023] Among them, the retention time of the material in the swelling tank in a plug flow manner is 30-60 minutes;

[0024] Step 5, secondary mixing:

[0025] The mixed material that has been swollen in step 4 is fed into a pipeline mixer, and a complexing agent is added into the pipeline mixer to be fully mixed with the mixed material in the pipeline mixer;

[0026] Wherein, the added amount of the complexing agent is 0.05-0.1% of the total weight of the crushed material;

[0027] Step 6, complexation:

[0028] The mixed material obtained in step 5 is pressed into the ion exchange tank in a plug flow manner to complete the exchange of metal ions;

[0029] The retention time of the mixture in the ion exchange tank in a plug flow manner is 30-60 minutes;

[0030] Step 7, post-processing:

[0031] The material obtained through the complexation in step six is ​​dehydrated, washed and dried to complete the purification of the soybean dietary fiber.

[0032] In step 1, the hemicellulose solvent is hydrogen peroxide.

[0033] In step 3, the ammonium ion used is ammonia water or ammonium bicarbonate.

[0034] In step five, the complexing agent is a soluble soybean polysaccharide with a low esterification degree, where the low esterification degree means that the carboxyl esterification portion does not exceed 7%. The soluble soybean polysaccharide is essentially water-soluble soybean fiber, which acts as an ion exchange medium. After complexing metal ions, they are removed with the liquid phase, and the residual portion does not affect the purity of the soybean fiber.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The purification system and purification process adopted by the present invention firstly disperse and crush soybean dietary fiber with large particle clusters into small particle molecular structures through mechanical crushing, thereby providing a basic environment for subsequent removal of protein and metal ions; secondly, by adding a hemicellulose cosolvent and coordinating a swelling process, hemicellulose, pectin and the like used for connecting the molecular structure between soybean dietary fiber molecules are dissolved, so that the soybean dietary fiber molecular structure is further opened, most of the metal ions carried on the fiber are exposed, and a favorable environment is provided for the removal of the metal ions; in addition, the addition of ammonium ions can further promote the opening of the soybean dietary fiber molecular structure, and the alkaline environment provided by the ammonium ions can also dissolve most of the alkali-soluble soybean protein carried in the fiber, thereby achieving the purpose of removing the protein; finally, by adding a complexing agent, the metal ions in the fiber are complexed and separated, thereby completely completing the purification of the soybean dietary fiber; the purity of the obtained soybean dietary fiber can reach about 80%, which can fully meet the use of the pharmaceutical industry and some industries with high requirements for the purity of the soybean dietary fiber, and get rid of the current situation that these industries must rely on imported high-purity soybean dietary fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of the system of the present invention;

[0038] Figure 2 Schematic diagram of the partially enlarged structure of the conical wire-wound filter.

[0039] Markings in the figure: 1. High-pressure plunger pump, 2. Zoom-in nozzle, 3. Crushing tank, 4. Mixing tank, 5. Swelling tank, 6. Pipeline mixer, 7. Ion exchange tank, 8. Conical wire-wound filter, 9. Heating sleeve, 10. Return pipe. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with specific embodiments.

[0041] First, the present invention provides a soybean dietary fiber purification system, comprising a high-pressure plunger pump 1, a convergent-divergent nozzle 2, a crushing tank 3, a mixing tank 4, a swelling tank 5, a pipeline mixer 6 and an ion exchange tank 7, wherein the outlet of the high-pressure plunger pump 1 is connected to the inlet of the convergent-divergent nozzle 2 through a pipeline, the outlet of the convergent-divergent nozzle 2 is connected to the inlet of one side of the crushing tank 3, and a reflux pipeline 10 connected to the high-pressure plunger pump 1 is arranged at the bottom of the crushing tank 3; a conical wire-wound filter screen 8 is arranged in the crushing tank 3, the tip of the conical wire-wound filter screen 8 is horizontally placed in the outlet pipe mouth of the convergent-divergent nozzle 2, and the large-diameter open end of the conical wire-wound filter screen 8 is connected to the inlet of one side of the mixing tank 4, and the crushing tank 3 and the mixing tank 4 are a square joint structure; a stirring mechanism is arranged in the mixing tank 4, see Figure 1 The stirring mechanism includes a stirring motor arranged on the top of the tank body and a stirring rod arranged in the tank body, the stirring rod is provided with a stirring blade, and generally the stirring blade is further provided with a through hole to promote the mixing effect; the bottom outlet of the mixing tank 4 is connected to the bottom inlet of the swelling tank 5 through a feeding pipe and a feeding pump, the outer circumference of the swelling tank 5 is sleeved with a heating sleeve 9 with sealed ends, the cavity between the heating sleeve 9 and the swelling tank 5 is a steam heating cavity, and a steam inlet is provided on one side of the heating sleeve 9; the top outlet of the swelling tank 5 is connected to the pipeline mixer 6 through a pipeline, the outlet of the pipeline mixer 6 is connected to the bottom inlet of the ion exchange tank 7 through a pipeline, and the top of the ion exchange tank 7 is provided with a discharge port.

[0042] In this embodiment, the conical wire-wound filter 8 is formed by winding a metal wire along a cone structure, and the gap between any two adjacent circles of the metal wire is the filtering gap; the vertical cross-section of the metal wire is a trapezoidal structure, and the filtering gap is 15-50 microns. The conical wire-wound filter 8 under this structure has the best crushing effect.

[0043] The mixed material solution is accelerated and dispersed after passing through the high-pressure plunger pump 1 and the convergent-divergent nozzle 2 and is pumped onto the conical wire-wound filter screen 8. The soybean dietary fiber clusters impact the conical wire-wound filter screen 8 head-on, so that the large particles of the clusters are impacted and broken into small particle molecular structures. The broken fiber molecules pass through the filtering gap on the conical wire-wound filter screen 8 and flow into the mixing tank 4. The fibers that are not broken or not completely broken fall down, circulate back through the reflux pipe 10 and enter the high-pressure plunger pump 1, and are crushed after being pumped out again.

[0044] On the one hand, the soybean dietary fiber entering the crushing tank 3 is first mixed with the hemicellulose cosolvent, under the action of which the hemicellulose and pectin used to connect the soybean dietary fiber molecules are gradually dissolved, so that the soybean dietary fiber molecules are freed from the constraints, and then the structure of the fiber molecules is opened, and the metal ions carried on the fiber are exposed, providing a good foundation for the subsequent complexation and removal of metal ions; at the same time, in this process, a part of the metal ions existing in the hemicellulose and pectin will be synchronously separated from the soybean dietary fiber molecules as the hemicellulose and pectin are dissolved; in the crushing tank 3, under the dual action of mechanical impact crushing and hemicellulose cosolvent, the fiber molecular structure of the soybean dietary fiber is opened, and most of the metal ions are exposed.

[0045] On the other hand, the soybean dietary fiber that enters the mixing tank 4 after being crushed is mixed with the ammonium ions and then enters the swelling tank 5 together. Since the crystalline area of ​​the soybean dietary fiber is dense, there are substances such as semi-fiber and protein between the fibers, and some of them are even chemically bonded. After the ammonium ions are added, during the high-temperature swelling process in the swelling tank, the ammonium ions can destroy the hydrogen bond structure between the fiber molecules, and the hydrogen bond structure between the soybean dietary fiber molecules is further broken, the connection between the fiber molecules is further opened, the metal ions are further exposed, and the system ion strength is enhanced, creating conditions for the control of the inorganic mineral content. At the same time, the alkaline environment provided by the ammonium ions can gradually dissolve the protein.

[0046] Secondly, the present invention provides a soybean dietary fiber purification process, comprising the following steps:

[0047] Step 1: Mechanical crushing:

[0048] The material is sent into the convergent-divergent nozzle 2 through the high-pressure plunger pump 1, and is accelerated by the convergent-divergent nozzle 2 to hit the conical wire-wound filter 8 in the crushing tank 3 to complete mechanical crushing. At the same time, hemicellulose co-solvent is added to the crushing tank 3 during the crushing process;

[0049] Wherein, the material is a soybean dietary fiber solution obtained by mixing soybean dietary fiber powder and distilled water in a weight ratio of 1:20-25; in this embodiment, the soybean dietary fiber powder and distilled water are in a weight ratio of 1:20;

[0050] Step 2, mechanical filtration:

[0051] The mechanically crushed material passes through the filter gap on the conical wire mesh 8 and enters the inner cavity of the conical wire mesh 8, and naturally flows into the mixing tank 4. The uncrushed or incompletely crushed material is re-sent to the high-pressure plunger pump 1 through the return pipe 10 at the bottom of the crushing tank 4;

[0052] Step 3, one-time mixing:

[0053] Add ammonium ions into the mixing tank 4, and stir and mix them with the materials entering the mixing tank 4;

[0054] The amount of ammonium ions added is 0.1-0.3% of the total weight of the crushed material, and the pH value of the mixed material in the mixing tank 4 is controlled at 8-9;

[0055] Step 4: Swelling:

[0056] Steam is introduced into the heating sleeve 9 to keep the temperature in the swelling tank 5 at 75-90 degrees Celsius, and then the mixture obtained in step 3 is pressed into the swelling tank 5 in a plug flow manner;

[0057] The retention time of the material in the swelling tank 5 in a plug flow manner is 30-60 minutes;

[0058] Step 5, secondary mixing:

[0059] The mixed material that has been swollen in step 4 is fed into the pipeline mixer 6, and a complexing agent is added into the pipeline mixer 6 to be fully mixed with the mixed material in the pipeline mixer 6;

[0060] Wherein, the added amount of the complexing agent is 0.05-0.1% of the total weight of the crushed material;

[0061] Step 6, complexation:

[0062] The mixed material obtained in step 5 is pressed into the ion exchange tank 7 in a plug flow manner to complete the exchange of metal ions;

[0063] The retention time of the mixture in the ion exchange tank 7 in a plug flow manner is 30-60 minutes;

[0064] Step 7, post-processing:

[0065] The material obtained through the complexation in step six is ​​dehydrated, washed and dried to complete the purification of the soybean dietary fiber.

[0066] In step 1, the hemicellulose solvent is hydrogen peroxide.

[0067] In step 3, the ammonium ion used is ammonia water or ammonium bicarbonate.

[0068] In step 5, the complexing agent is a soluble soybean polysaccharide with a low esterification degree, and the low esterification degree means that the carboxyl esterification part does not exceed 7%.

[0069] The core idea of ​​the soybean dietary fiber purification process described in the present invention is that the clustered soybean dietary fiber structure is opened by mechanical crushing of fiber particles and chemical crushing such as swelling of fiber crystal regions, thereby exposing the metal ions and proteins doped in the fiber, and providing a basis for controlling the sodium ion, potassium ion, calcium ion, iron ion, magnesium ion, phosphate ion and protein content in the soybean fiber. Among them, the protein is dissolved and removed by alkaline environment, and the metal ions are removed by complexing with carboxyl-containing soluble soybean polysaccharides. The soluble soybean polysaccharides need to maintain a low degree of esterification so that the carboxyl groups in their molecular structure are as many as possible, so as to adsorb as many metal ions as possible through the carboxyl groups. In addition, the soluble soybean polysaccharides themselves are a kind of water-soluble soybean fiber. The soybean polysaccharides are used as complexing agents. While complexing metal ions, other impurities will not be introduced into the molecular structure of the soybean dietary fiber, thereby ensuring the purity of the soybean dietary fiber.

[0070] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A soybean dietary fiber purification system, characterized in that: The invention comprises a high-pressure plunger pump (1), a convergent-divergent nozzle (2), a crushing tank (3), a mixing tank (4), a swelling tank (5), a pipeline mixer (6) and an ion exchange tank (7), wherein the outlet of the high-pressure plunger pump (1) is connected to the inlet of the convergent-divergent nozzle (2) through a pipeline, the outlet of the convergent-divergent nozzle (2) is connected to the inlet of one side of the crushing tank (3), and a conical wire-wound filter screen (8) is arranged in the crushing tank (3), and the tip of the conical wire-wound filter screen (8) is horizontally placed in the outlet pipe opening of the convergent-divergent nozzle (2). The large-diameter open end of the conical wire-wound filter (8) is connected to the inlet on one side of the mixing tank (4), a stirring mechanism is provided in the mixing tank (4), the bottom outlet of the mixing tank (4) is connected to the bottom inlet of the swelling tank (5) through a feeding pipeline and a feeding pump, the top outlet of the swelling tank (5) is connected to the pipeline mixer (6) through a pipeline, the outlet of the pipeline mixer (6) is connected to the bottom inlet of the ion exchange tank (7) through a pipeline, and the top of the ion exchange tank (7) is provided with a discharge port; The outer circumference of the swelling tank (5) is provided with a heating sleeve (9) with sealed ends; the cavity between the heating sleeve (9) and the swelling tank (5) is a steam heating cavity; and a steam inlet is provided on one side of the heating sleeve (9); The conical wire-wound filter (8) is formed by winding a metal wire along a conical structure, and the gap between any two adjacent turns of the metal wire is a filtering gap; A return pipe (10) connected to the high-pressure plunger pump (1) is provided at the bottom of the crushing tank (3).

2. A soybean dietary fiber purification system as claimed in claim 1, characterized in that: The vertical cross section of the metal wire is a trapezoidal structure, and the filtering gap is 15-50 microns.

3. A soybean dietary fiber purification system as claimed in claim 1, characterized in that: The crushing tank (3) and the mixing tank (4) are of a square joint structure.

4. A process for purifying soybean dietary fiber using the system according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: Mechanical crushing: The material is fed into the divergent nozzle (2) through a high-pressure plunger pump (1), and is accelerated through the divergent nozzle (2) to impact the conical wire mesh filter (8) in the crushing tank (3), thereby completing mechanical crushing. At the same time, a hemicellulose solvent is added to the crushing tank (3) during the crushing process; Wherein, the material is a soybean dietary fiber solution obtained by mixing soybean dietary fiber powder and distilled water in a weight ratio of 1: (20-25); Step 2, mechanical filtration: The mechanically crushed material passes through the filter gap on the conical wire mesh filter (8) and enters the inner cavity of the conical wire mesh filter (8), and naturally flows into the mixing tank (4). The material that has not been crushed or has not been completely crushed is re-sent to the high-pressure plunger pump (1) through the return pipe (10) at the bottom of the crushing tank (3); Step 3, one-time mixing: Adding ammonium ions into the mixing tank (4) to fully stir and mix the ammonium ions with the materials entering the mixing tank (4); The amount of ammonium ions added is 0.1-0.3% of the total weight of the crushed material, and the pH value of the mixed material in the mixing tank (4) is controlled at 8-9; Step 4: Swelling: Steam is introduced into the heating sleeve (9) to maintain the temperature in the swelling tank (5) at 75-90 degrees Celsius, and then the mixture obtained in step 3 is pressed into the swelling tank (5) in a plug flow manner; The retention time of the material in the swelling tank (5) in a plug flow manner is 30-60 minutes; Step 5, secondary mixing: The mixed material that has been swollen in step 4 is fed into the pipeline mixer (6), and at the same time, a complexing agent is added into the pipeline mixer (6) so that the complexing agent and the mixed material are fully mixed in the pipeline mixer (6); Wherein, the complexing agent is a low-esterification soluble soybean polysaccharide with a carboxyl esterification part of no more than 7%; the amount of the complexing agent added is 0.05-0.1% of the total weight of the crushed material; Step 6, complexation: The mixed material obtained in step 5 is pressed into the ion exchange tank (7) in a plug flow manner to complete the exchange of metal ions; The retention time of the mixed material in the ion exchange tank (7) in a plug flow manner is 30-60 minutes; Step 7, post-processing: The material obtained through the complexation in step six is ​​dehydrated, washed and dried to complete the purification of the soybean dietary fiber.

5. A soybean dietary fiber purification process as claimed in claim 4, characterized in that: In step 1, the hemicellulose solvent is hydrogen peroxide.

6. A soybean dietary fiber purification process as claimed in claim 4, characterized in that: In step 3, the ammonium ion used is ammonia water or ammonium bicarbonate.

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