CN109675677B - Flour production process and flour production system - Google Patents

Abstract

The invention discloses a flour production process and a flour production system. The flour production process comprises the following steps: preparing a flour raw material; the method comprises the following steps of putting flour raw materials into a vibration grinding unit comprising a vibration mill and a classifying screen, and grinding and screening the flour raw materials through the vibration mill and the classifying screen to form undersize materials in multiple stages; and obtaining products formed by crushing parts with different looseness in the flour raw materials from the undersize materials in different stages. The staged thinning is realized through the vibration grinding process, the pretreatment procedures such as wheat wetting and the post-treatment procedures such as loosening and cleaning are not needed, and the production efficiency is higher; the stress state of the ground material is short (instantaneous) stress, so that selective crushing is realized, the part which is easy to crush is discharged in advance, and excessive crushing is avoided; the materials are not easy to be oxidized, and no additional antioxidant treatment is needed, so that the process cost is reduced.

Description

Flour production process and flour production system

Technical Field

The invention relates to the field of food processing, in particular to a flour production process and a flour production system.

Background

Roller milling has now become the standard method in the global flour industry since 1886 in place of millstones for thousands of years, and the roller milling process is described in detail below.

The existing roller flour production process consists of four systems, namely a skin mill system, a core mill system, a slag mill system and a flour cleaning system. The wheat bran and wheat kernel extracting system comprises a front path of skin mill and a rear path of skin mill, wherein the front path of skin mill is used for peeling wheat grains and extracting wheat residues and wheat kernels to the maximum extent, and the rear path of skin mill is used for scraping endosperm. The core grinding system is used for grinding endosperm into powder, the powder cleaning system and the slag grinding system are a link connecting a skin mill and the core mill, and play an important role in producing high-precision flour. Therefore, the slag grinding and powder cleaning system plays a role in the fine selection and purification of materials in the powder preparation process.

Although the tasks of the slag mill and the flour cleaning system are consistent in the flour path, the principles of purification and selection of the slag mill and the flour cleaning system are different, the slag mill utilizes the mechanical action of a grinding roller to strip wheat bran on the pericarp endosperm (wheat residue) but cannot purify a material mixture, and the flour cleaning utilizes the combined action of an air screen to purify the material mixture but cannot separate the wheat bran on the residue grains. Therefore, without slag milling, more pure endosperm can not be produced, without powder cleaning, the purest endosperm particles can not be provided, the amount of slag milling can be increased, the quality of powder cleaning can be ensured, the slag milling and the powder cleaning are mutually matched, mutually complement and purify in a cross way, and the slag milling and the powder cleaning share the function of providing more pure endosperm with better quality for the previous heart milling.

In addition, the pretreatment of the existing flour production process basically comprises a wheat wetting procedure, and the main purpose of wheat wetting is to increase the toughness of the cortex and improve the crushing difficulty of the cortex so as to reduce the bran content of the flour. In the post-step of the roller grinding, a flour loosening machine and a flour purifier are required, wherein the flour loosening machine is used for loosening the endosperm adhered to the slices, and the flour purifier is used for grading the light bran, the endosperm with the bran and the endosperm so as to reduce the bran content of the flour and the flour content of the bran.

The existing roller grinding has the following characteristics:

the material is stressed in a short time between the rollers, and the stress direction is single, namely the material is stressed by the shearing force and the positive pressure with fixed directions. The air low pressure along the roller surface layer formed by the rotation of the roller surface is easy to make the sheet material parallelly close to the roller surface and keep the state to enter the gap between the two rollers. The result is that the tough material in the wheat grains is still flaky after more times of crushing, and the thickness and the size of the flaky material are gradually reduced.

Roller milling has the inherent characteristic of selective comminution, i.e., roller milling preferentially comminutes brittle endosperm, whereas tough bran and germ fractions tend to flake under the force of roller milling, thus facilitating separation of endosperm from bran and germ, but not comminute tough materials.

According to the principle of long grinding path of few-grinding, multiple-screen and light-grinding, the roller grinding is combined with wind power/screening classification to reduce over-grinding, so that the grinding efficiency is greatly improved, and the method is suitable for the purposes of low wheat bran powder content, reduction of bran star content of flour, avoidance of starch grain damage, improvement of flour whiteness and the like.

At present, the flour production process adopted at home and abroad is to gradually grind by using roller grinding and distinguish bran flour and endosperm flour by a screening mode. The texture structure of wheat cortex is tight and tough, while the texture structure of wheat endosperm is relatively loose and soft, so that the granularity of the crushed particles of the two is different under the same pressure, shearing force and cutting force, and the cortex flour and the endosperm flour with different granularities are distinguished by using a screening mode, thereby achieving the purposes of removing bran and retaining flour.

The granularity difference between the skin layer and the endosperm after crushing is related to the applied force, the larger the applied force is, such as one-time crushing, the difference degree is very small, the flour and the bran are difficult to screen and separate, while the smaller the applied force is, such as multiple times of applied force, the difference degree is increased, the screening efficiency is improved, the purity of the flour is improved, and the principle of light milling and subdivision of modern flour milling is adopted. It is clear that the process of modern milling is open to the theme of expanding the particle size difference between the broken skin and endosperm, such as wheat wetting, loose flour, smooth roller techniques, etc.

Thus, the existing flour production process using the roller milling technique has the following drawbacks:

firstly, the method comprises a wheat wetting pretreatment process and a flour loosening and cleaning post-treatment process, the number of the processes is large, the production efficiency is low, and the bran content of 85 flour is not low, and the color of the flour is dark;

second, the material (such as wheat) is sufficiently contacted with water in the wheat wetting process and is exposed to air and warm conditions in the subsequent process, so that the material is easily oxidized, and additional anti-oxidation treatment is required, thereby increasing the process cost.

Disclosure of Invention

In order to solve the above technical problems, the present invention aims to provide a flour production process and a flour production system, which have high production efficiency and low production cost.

The invention provides a flour production process, which comprises the following steps: preparing a flour raw material; feeding the flour feedstock into a vibratory grinding unit comprising a vibratory mill and a classifying screen, the flour feedstock forming a plurality of stages of undersize material by grinding and screening of the vibratory mill and the classifying screen; and obtaining products formed by crushing parts with different porosities in the flour raw material from the undersize materials in different stages.

Preferably, the flour feedstock is ground and sieved by the vibratory mill and the classifying screen to form an oversize material from which bran is obtained and a flour is obtained from the undersize material.

Preferably, the bran is put into a first vibration grinding unit to obtain an oversize bran material and an undersize bran material, and the oversize bran material is put into the first vibration grinding unit or another vibration grinding unit again to obtain the next oversize bran material and undersize bran material; when the oversize bran material is no longer screened, the entire undersize bran material is collected to obtain a fine bran product.

Preferably, the flour and the fine bran product are mixed to obtain a fine bran whole wheat flour.

Preferably, the flour raw material is ground and sieved by the vibration mill and the classifying screen to form an oversize material corresponding to the undersize materials of a plurality of stages, and the oversize material is fed into the same vibration grinding unit or different vibration grinding units to form the oversize material and the undersize material of the next stage; the grinding time and the magnitude of stress of the vibratory mill of the vibratory grinding unit are adjusted to obtain the corncob meal first by the undersize material previously screened and to obtain the endosperm meal having a gluten quality slightly inferior to the corncob meal by the undersize material screened later.

Preferably, the flour and the bran are mixed together to obtain a coarse bran whole wheat flour.

Preferably, gas which flows from a feed inlet to a discharge outlet of the vibration mill is introduced into the vibration grinding unit, and the gas passes through the vibration mill.

Preferably, the dried flour feedstock is fed to the vibratory grinding unit.

Preferably, the flour raw materials are: one or more of wheat, barley, oat, corn, rice, rye, triticale, sorghum, millet, buckwheat, quinoa, grain amaranth, highland barley, soybean, black bean, green bean, pea, broad bean, mung bean, red bean and small red bean.

Preferably, the vibration frequency of the vibration mill is 8HZ to 50HZ, the amplitude of the vibration mill is 2mm to 9mm, and the vibration acceleration of the vibration mill is 2g to 10g, so that the bran micro-particles are precisely compounded.

Preferably, the bran contains phytic acid and phytase, the bran is fed into the vibratory grinding unit to precision complex the micro-particles of the bran and place the phytase in an inhibited state, and the phytic acid is released from the bran and redistributed in the fine bran whole wheat flour to achieve phytic acid secondary protection.

Preferably, the bran contains phytic acid and phytase, the undersize material comprising flour and a fine bran product, the flour and the fine bran product being obtained separately such that the phytic acid and phytase are substantially entirely within the fine bran product.

Preferably, the bran comprises phytase, lipase and lipoxygenase, the temperature of the ground material is controlled not to exceed 40 ℃ and/or the dry flour feedstock is fed to the vibratory grinding unit to inhibit the activity of the phytase and/or lipase and/or lipoxygenase.

Preferably, the bran contains lipoxygenase, and an inert gas is injected into the milling drum of the vibratory mill, the fat in the flour feedstock is substantially free of oxygen, and the lipoxygenase is in an inhibited state.

The present invention also provides a flour production system comprising a vibratory grinding unit comprising: the vibration mill comprises a milling cylinder and milling bodies, wherein the milling cylinder performs circular vibration, and a plurality of milling bodies are freely placed in the milling cylinder; a classifying screen connected to a discharge port of the grinding drum to screen the ground flour raw material; the flour raw material is sequentially ground by the vibration mill and sieved by the grading sieve to form undersize materials in different stages, and products formed by crushing various parts with different looseness in the flour raw material are obtained from the undersize materials in different stages.

Preferably, the outer peripheral wall of the grinding cylinder is sleeved with a cooling water jacket, and the cooling water jacket is filled with flowing cooling water which is not higher than room temperature.

Preferably, the grinding cylinder is filled with inert gas.

The technical scheme provided by the invention has the following beneficial effects:

firstly, the grinding (i.e. vibration grinding) is realized by high-frequency vibration, and different flour products, such as an endosperm part, a bran part and a germ part, can be finely ground by stages by using the characteristic of fragility of different parts of a flour raw material, such as wheat grains, without a pretreatment process of wetting wheat and a post-treatment process of loosening the flour, cleaning the flour and the like, so that the production efficiency is high;

secondly, the ground materials in the grinding cylinder are stressed in a short (instant) time, and selective grinding can be effectively realized only by the short (instant) time, so that the parts which are easy to break are discharged in advance, and excessive grinding is avoided;

thirdly, compared with roller type grinding, the power required by the impact provided by vibration grinding is relatively much smaller, the energy consumption of the system is saved, and the cost is reduced;

fourthly, the materials are not easy to be oxidized, and no additional anti-oxidation treatment is needed, so that the process cost is reduced.

Drawings

FIG. 1 is a schematic view of the operation of a vibratory mill of a vibratory finishing unit provided in accordance with the present invention;

FIG. 2 is a diagram illustrating the analysis of the stress state of the vibratory mill of the vibratory grinding unit according to the present invention when processing materials;

FIG. 3 is a flow diagram of one embodiment of a flour production process provided by the present invention;

FIG. 4 is a flow diagram of one example of a continuous production scheme for the flour production process provided by the present invention;

FIG. 5 is a flow diagram of yet another example of a continuous production protocol for the flour production process provided by the present invention;

FIG. 6 is a flow diagram of yet another example of a continuous production protocol for the flour production process provided by the present invention;

FIG. 7 is a flow diagram of another example of a continuous production protocol for the flour production process provided by the present invention;

FIG. 8 is a flow diagram of another example of a continuous production protocol for the flour production process provided by the present invention;

FIG. 9 is a flow diagram of another example of a continuous production protocol for the flour production process provided by the present invention;

FIG. 10 is a flow diagram of another example of a cyclical production scheme for a flour production process provided by the present invention.

Description of reference numerals:

10 vibrating the grinding unit; 100, grinding a cylinder; 200 grinding body; 300, preparing materials; p high acceleration impact force; l shear force.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The invention discloses a flour production process and a flour production system, and firstly introduces the flour production system provided by the invention.

The flour production system is provided with at least one vibration grinding unit, each vibration grinding unit comprises a vibration mill and a grading sieve, the vibration mill is used for performing vibration grinding on flour raw materials, and the grading sieve is used for separating materials with different particle sizes, so that the roller type grinding of the flour in the traditional process is replaced.

The vibration grinding tool is provided with a grinding cylinder and a grinding body, the grinding cylinder can do circular vibration, and the circular vibration means that: the vibration mode is circular, elliptical or other shape similar to circular vibration, so to speak, the grinding cylinder does circular motion while vibrating, or the grinding cylinder forms circular motion track while vibrating. The grinding cylinder is provided with a cylindrical cavity capable of containing materials, a plurality of grinding bodies are freely placed in the grinding cylinder, and the grinding bodies are in a shape with a rotating axis, such as a rod, a short column, a ball and the like.

As shown in fig. 1, when the grinding cylinder 100 is started, the grinding bodies 200 rotate and vibrate around their own axes (i.e., the grinding bodies 200 rotate) along with the circular vibration of the grinding cylinder 100, and at the same time, the group of grinding bodies 200 rotates and vibrates around the axis of the grinding cylinder 100 (i.e., the grinding body group revolves) (the axis is shifted due to the influence of the medium filling rate), and the material 300 between the grinding bodies 200, i.e., the flour material, is collided, pressed and sheared by the grinding bodies 200 in the grinding cylinder 100, and the material is brought into a boiling state, which is called fluidization.

The flour production system has, in addition to the vibratory grinding units, a conveying system for conveying the flour feedstock to and/or from the vibratory grinding units and/or conveying the material between the vibratory grinding units.

The flour production system provided by the invention can isolate external air at least in the vibration grinding unit, and can further preferably fill inert gas such as nitrogen, carbon dioxide, argon and the like and combinations thereof, such as O, in the grinding cylinder and the classifying screen space ₂ +CO ₂ +N ₂ ，N ₂ +CO ₂ ，O ₂ +CO ₂ 。

The grinding cylinder is further sleeved with a cooling water jacket for timely heat dissipation, and flowing cooling water with the temperature not higher than room temperature is introduced into the cooling water jacket, so that the grinding temperature of the materials is not higher than 50 ℃, the optimized temperature is not higher than 40 ℃, and the optimized temperature is not higher than 35 ℃.

In traditional roll-type grinding system, less configuration roller internal cooling water because easily receive the environmental impact to produce uncontrollable comdenstion water under its production condition, form the frictional force difference between roll surface and the material, increase material moisture and the rusty risk in cylinder surface. Therefore, the traditional roller mill mostly adopts an air cooling scheme, the temperature of the roller surface is more than 70 ℃ to 90 ℃, and adverse effects are brought to the quality of flour, including reduction of gluten strength, increase of oxidation risk and the like.

In addition, in the traditional roller type grinding system, air conveying is basically adopted, a plurality of advantages are provided for a roller type grinding main machine system, the open type grinding machine adopts negative pressure dust prevention integration and also has a cooling effect, the water content can be balanced, the pipeline materials are prevented from being attached to stored materials or mildewing, the functions of dispersing the materials are also achieved, the multi-point feeding is convenient to convey, and the technological requirements of equipment (such as a purifier) are met. However, in the open type operation mode, the material is completely exposed to the atmosphere, and if the inert gas protection is required, no practical significance is realized in both the technical angle and the cost angle.

Therefore, in the existing production system, it is expected that the exposed germs are hardly oxidized, and especially under the conditions of moisture (from a wheat wetting process), oxygen (from an open system) and temperature (the surface temperature of a grinding roller reaches 70-90 ℃, materials rapidly pass through the surface of the grinding roller, and the temperature rapidly exceeds the room temperature) which are three vital factors of grains such as wheat, the original cortex protection system of the grains such as the wheat is opened, and the oxidation becomes necessary.

The invention has no specific requirement on a conveying system, and because the cooling water jacket is sleeved outside the grinding cylinder, materials can be cooled by the jacket water, and large air volume cooling (namely air cooling) is not needed. Both the feeding and the discharging can be connected to the vibration grinding unit through a closed flexible connection, and negative pressure dust prevention is not a necessary condition. The material in the grinding cylinder is in a fluidized powder state, and wheat wetting and water balancing are not needed. Due to the fact that the device is provided with a fully-closed device operation foundation, inert gas (such as nitrogen) can be used for protection in the whole production process. Therefore, the system has the capability of avoiding the oxidation of the germ, and the prepared bran can be used as food-grade products.

To avoid oxidation, closed delivery may also be used, and delivery systems may use, but are not limited to: bucket elevators, pipe chain conveyors, screw conveyors, vibratory conveyors, scraper conveyors, pneumatic conveyors, and the like.

Where the flour production system has a plurality of vibratory grinding units, the classifying screen of each vibratory grinding unit may have a different size mesh, for example, the vibratory grinding units may be arranged along the flour production process line with the mesh of the upstream classifying screen being smaller than or equal to the mesh of the downstream classifying screen. The vibration mill of one vibration grinding unit is connected with the grading sieve of another vibration grinding unit, flour raw materials firstly enter one vibration grinding unit, formed materials on the sieve sequentially enter the subsequent vibration grinding units, and therefore the vibration grinding units sequentially form flour or bran.

The grinding drum of a vibratory mill can have three forms: the first is feeding from one end and discharging from the other end; the second is feeding from the middle and discharging from the two ends; the third is feeding from both ends and discharging from the middle. The grinding cylinders in the above three forms can be combined for use, wherein the second type and the third type can be combined for use along the up-down direction, namely, the materials are fed from the middle of the second type of grinding cylinder, enter the two ends of the third type of grinding cylinder after passing through the two ends of the second type of grinding cylinder, and are discharged from the middle of the third type of grinding cylinder. To separate the grinding bodies from the material, a sieve plate is generally provided at the discharge end.

The flour raw material is sequentially subjected to grinding of the vibration mill and screening of the classifying screen in the vibration grinding unit to form undersize materials of at least one stage, and oversize materials corresponding to the undersize materials of each stage can also be formed.

When the flour raw material is grain such as wheat with bran, the wheat core powder and endosperm powder formed by the wheat core part and the endosperm part with different bulkiness can be obtained by sieving the material, and the bran can be obtained by sieving the material.

When the flour raw material is grains such as rice without bran, powdery products formed by various parts with different porosity can be obtained by sieving the materials.

It is to be understood that reference to flour in the present invention is intended to refer to wheat, barley, oats, corn, rice, rye, triticale, sorghum, millet, buckwheat, quinoa, grain amaranth; or the corresponding powder products produced by taking highland barley, soybean, black bean, green bean, pea, broad bean, mung bean, red bean, small red bean and other grains as raw materials.

The invention will be illustrated below with wheat as the flour raw material.

The mechanism of the vibratory finishing employed in the present invention is analyzed below.

The pulverization can be classified into non-compression pulverization and compression pulverization according to the mode of force. The instantaneous crushing force applied to the material by the non-compression crushing is unidirectional. To achieve a sufficient impulse, the quality is equally important except for the speed according to the formula F Δ t — M Δ V. Taking jet milling as an example, the mass of the material is too small and the impact energy generated is very limited. And the wheat is an elastic body, the materials generated by high-speed airflow collide or impact easily generate rebound of particles rotating at high speed, the energy of the particles is still reflected in a high-speed motion form and is difficult to be changed into surface energy after the particles are refined, and therefore the crushing efficiency is low. During rotor crushing, high-speed friction is formed between materials and equipment rotors, and because the heat conductivity of each component of wheat is poor, the heat capacity is low, the friction force is strong, and in addition, the cooling area of the equipment is too small, and non-contact cooling is performed, the temperature rise of the materials is inevitably too high.

The compression crushing is that the materials are simultaneously extruded by bidirectional (opposite) acting force in the crushing process. This approach is more effective for wheat with low specific gravity, softness, toughness and deformability.

As shown in figure 2, the invention adopts vibration grinding instead of traditional roller grinding, wherein acting force is applied to the flour raw material in a shearing-compression crushing mode, the flour raw material is subjected to the combined action of high-acceleration impact force P and shearing force L, so that the flour raw material is compressed, torn and crushed under the action of bidirectional composite force, and the crushing acting force is not influenced by the mass of the material. When the method is adopted to crush the fibrous materials, the tissue structure and the fibers are easy to damage due to the strong compression tearing acting force. Under the action of external exciting force, the grinding body makes throwing motion of time dispersion and time polymerization. The grinding bodies rotate in the same direction, and the grinding body group revolves. The inner and outer layer grinding bodies exchange positions continuously, and materials are impacted, extruded and sheared continuously between every two grinding bodies, so that the materials are broken and sheared. The particles are broken continuously from large to small. In the crushing process, larger particles are stressed first and are crushed first.

The particles consisting of plant cell groups, whether the particles consist of large cells or small cell groups, are compressed and have equal chances of being impacted as long as the overall size is equivalent. That is, in the process of crushing wheat, the probability of crushing is the same for both large cell groups and small cell groups as long as the whole size is equivalent to the whole size.

In the vibration grinding process, the probability stress times (including uniformity) can be adjusted by adjusting the macroscopic stress time (vibration grinding time), the microscopic stress state can be adjusted by adjusting the macroscopic stress size, namely, the critical impact speed of a grinding body is adjusted by adjusting the vibration acceleration and the frequency of a grinding cylinder, in a momentum calculation formula F delta t of wheat, M is equivalent to the weight of the grinding body, delta V is related to the acceleration of gravity and the frequency, F is equivalent to the product of the weight of the grinding body and the acceleration of gravity, and delta t is limited by the frequency.

Roller grinding and vibration grinding both belong to compression type grinding, the former relies on static positive pressure and shearing force between two rollers, and the latter relies on impact between a grinding body and/or between the grinding body and a grinding cylinder to realize instantaneous positive pressure and shearing force.

Along with the circular vibration of the grinding cylinder, the grinding bodies can rotate around the axis of the grinding cylinder and rotate around the axis of the grinding cylinder, namely, the grinding bodies rotate around the axis of the grinding cylinder and revolve around the axis of the grinding cylinder simultaneously, and flour raw materials are contained in the grinding cylinder, so that the flour raw materials between the grinding bodies are collided, extruded and sheared by the grinding bodies in the grinding cylinder.

The present invention is a series of research and design on the vibratory mill of a vibratory grinding unit.

Based on a mechanical path method calculation principle, basic parameters such as mechanical path impedance, vibration mechanical power, vibration exciter load and the like are checked, stress and running state analysis is carried out, dynamic stiffness and dynamic strength are simulated, optimal vibration frequency and acceleration parameters are selected, and basic data design research of the vibration mill is carried out.

The equation of motion applicable to the present invention, and equations for calculating the vibration speed, amplitude, and amplitude of vibration speed of a grinding cylinder, the power of a vibration machine, the load of a vibration exciter, and the like, can be obtained from the application of the mechanical method in the research on vibration machines, which is the institute of foundry forging and stamping machines, the institute of mechanical industry, denna, in the first national "study on vibration machines and discussion on applied subject matters". The entire contents of this document are incorporated herein by reference and made a part of the disclosure of the present invention.

The flour production process provided by the invention utilizes the flour production system.

As shown in figure 3, by utilizing the vibration grinding principle, the flour production process provided by the invention comprises the following steps:

preparing flour raw materials which can be stored in a storage bin;

putting a flour raw material into a vibration grinding unit 10, specifically a vibration mill, circularly vibrating a grinding cylinder, grinding the flour raw material into a ground material by vibration grinding of the grinding cylinder, and screening the ground material by a classifying screen, so that the ground material is divided into an oversize material and an undersize material;

the undersize material may include a plurality of stages of undersize material, and products (such as wheat core flour and endosperm flour described below) formed by pulverizing various parts of the flour material with different porosities are obtained from the undersize material in different stages, and bran may also be obtained from the oversize material for grains with bran. The vibratory mill and the classifying screen of each vibratory grinding unit 10 cooperate to grind and subsequently screen the material.

In the most basic scheme of the flour production process provided by the invention, wheat is put into a grinding drum, the wheat is crushed under the collision, extrusion and shearing action of a grinding body in the grinding drum to form a ground material comprising endosperm flour and a skin layer, then a classifying screen is used for screening, flour formed by refining endosperm is screened to the undersize through the classifying screen to form an undersize material, and the skin layer is left on the screen of the classifying screen to form an oversize material.

The most basic flour production requirements can be met, namely flour refined by endosperm parts is obtained, and bran is removed completely, generally, about 80-85% of the endosperm parts can be obtained, the rest 15-20% of the endosperm parts are bran, and germs can be contained in the bran.

The production process provided by the invention utilizes the vibration grinding principle, the vibration can also generate high-strength audio frequency, the suspension and the dispersion of particles can be promoted, and meanwhile, the air film is attached to the surface of the powder, so that the good fluidity of the material can be formed.

In the application, the ground material in the grinding cylinder of the vibration mill is subjected to bidirectional force, namely, the particles are subjected to bidirectional force when being crushed, and the two stressed positions are basically symmetrical. The conventional rotor type crushing is typically subjected to unidirectional force, namely, particles are knocked by a high-speed hammer head, and the particles are instantaneously subjected to unidirectional force.

In the application, the stress state of the ground material in the grinding cylinder is short (instantaneous) stress, and selective crushing can be effectively realized only by short (instantaneous) stress, so that the part which is easy to crush is discharged in advance, and excessive crushing is avoided.

Because of the one-dimensional stress characteristic of roller grinding, selective crushing (endosperm crushing and bran removing) can be realized only by multiple times of force application under the matching of wheat wetting, flour loosening, flour cleaning and other processes; the acting force generated by the invention is a multidimensional stress state (the combined action of positive pressure, high shear force, high-frequency alternating force and full fluidized particle flow), and the optimization of selective crushing can be realized by adjusting the excitation parameters and the motion state of the material.

In the existing roller grinding, because the roller grinding is limited by the roller speed difference, the positive pressure is large, the stress time is not short enough, and the shearing force is not enough, the crushing selectivity is not strong (the bran is broken early or the endosperm is not dispersed) after the particles are crushed, and particularly, the bran is damaged greatly in the process of carrying the raw materials into the roller gap by using a toothed roller in the skin grinding process, so the roller passing times are not too many. A flour loosening machine (for loosening the endosperm adhered to the pieces) and a flour cleaning machine (for classifying the light bran, the endosperm with the bran and the endosperm) must be added in the subsequent processes to reduce the bran content of the flour and the flour content of the bran.

In the existing roller grinding, although the tasks of a slag grinding system and a powder cleaning system are consistent in a powder path, the principles of purification and selection of the slag grinding system and the powder cleaning system are different, the slag grinding system utilizes the mechanical action of a grinding roller to strip wheat bran on pericarp endosperm (wheat residue) but cannot purify a material mixture, and the powder cleaning system utilizes the combined action of an air screen to purify the material mixture but cannot separate the wheat bran on the wheat residue. Therefore, the pure endosperm can not be produced without slag grinding, the purest endosperm particles can not be provided without powder cleaning, the amount of slag grinding can be increased, the quality of the endosperm particles can be guaranteed by powder cleaning, and the slag grinding, the powder cleaning and the quality guarantee are mutually matched, complement and purified in a cross way, and share the function of providing the pure endosperm with large amount and good quality for the front-route heart grinding.

The invention applies instantaneous high pressure to endosperm by controlling the parameters of the vibration mill, and utilizes the instantaneous explosion effect formed by the internal stress rebound of starch particle groups in the endosperm to automatically disintegrate starch grains, the stress form of the invention is far superior to that of the traditional roller type grinding, and the damage degree of starch is lower. Meanwhile, materials in the grinding cavity are completely fluidized, two particle groups of crushed fine particles and incompletely crushed particles can be basically formed, and the particles can be clearly distinguished through one-time screening and classification, so that the system flow does not need a powder loosening machine and a powder cleaning machine in the existing flow.

The pretreatment of the existing flour production process basically adopts a wheat wetting procedure, and the main purpose is to increase the toughness of the cortex and improve the crushing difficulty of the cortex so as to reduce the bran content of the flour.

The vibration grinding mode adopted by the invention can accurately control the stress state of the particles and effectively realize selective crushing. In the flour production process provided by the invention, during grinding, ground materials, such as flour raw materials or oversize materials needing to be ground again, are subjected to high-frequency instantaneous impact, under the condition of sufficient impact force and impact speed, when particles are not deformed yet, the impact force is withdrawn, the internal stress of the particles still exists, and the explosion effect can occur due to the release of the stress. The advantages brought by the stress characteristic are as follows: the damage to the cortex is less, the particles in the inner part (pomegranate state formed by starch particles) can be exploded by stress, the damage to the starch particles is effectively avoided, the exploded particles are quickly dispersed due to the complete fluidization state in the vibration mill, and the endosperm and the cortex can be effectively separated without adding water to moisten the wheat under the condition of excellent selective crushing by the method due to the texture difference of the cortex and the endosperm. Therefore, the wheat wetting procedure for increasing the toughness of the bran is not a necessary condition of the method, and the flour cleaning process is not a necessary condition.

Moreover, in the flour production process of the present invention, the flour raw material (such as wheat) may be cleaned in a dry manner; or cleaning the flour raw material (such as wheat) by a wet method, and drying the wheat, namely quickly dehydrating the wheat, and further adopting a microwave drying mode which can further realize enzyme deactivation; further, a quick air drying mode can also be adopted.

In the flour production process of the present invention, the dry flour feedstock is fed into a vibratory grinding unit without the need for a wheat conditioning process.

Compared with the impact times, the vibration grinding mode provided by the invention realizes impact and shearing at the frequency of 16.7 times/s, and the crushing time of 10min is equivalent to that of 1 ten thousand times of roller grinding of materials.

Compared with critical stress, the positive pressure of the vibration grinding on the material is realized by impact force, and when the vibration acceleration of the grinding cylinder is 2-7 times of the gravity acceleration and even 7-10 times of the gravity acceleration, the material can obtain ideal impact force and be crushed. While roller grinding is achieved by static pressure, the power required for the impact provided by the vibratory grinding of the present invention is much less under conditions where the material achieves the same positive pressure.

In a further embodiment, the oversize material obtained from the flour raw material is subjected to at least one "grinding and subsequent sieving" as described above to obtain the next oversize material and undersize material, i.e. the oversize material obtained from the previous sieving is fed to a vibratory grinding unit for regrinding and rescreening, the undersize material from each sieving is collected to obtain flour, and the oversize material from the last sieving is collected to obtain bran. Each regrinding and rescreening process is a process of grinding and sifting oversize material obtained from the last sifting.

The scheme is a continuous production process, namely taking oversize materials obtained by last screening as raw materials for next vibration grinding, putting the oversize materials obtained by each time (each stage) into different vibration grinding units, grinding and then screening the oversize materials formed by each time (except for the last time), collecting undersize materials of each time of screening, namely refined flour, and collecting oversize materials of the last screening, namely bran.

The invention also provides a circulating production process, compared with the continuous production process, in the circulating production process, oversize materials in different stages are put into the same vibration grinding unit.

As shown in fig. 4, the ground material of the first grinding is subjected to sifting to obtain a first undersize material (flour 1) and an oversize material, the oversize material of the first grinding and then sifted to obtain a second undersize material (flour 2) and an oversize material, the oversize material of the second grinding and then sifted to obtain a third undersize material (flour 3) and an oversize material … … the oversize material of the (n-1) th grinding and then sifted to obtain an undersize material (flour n) and an oversize material of the nth time, the oversize material of the last grinding to obtain bran, and the undersize material of each time is collected to obtain flour.

As shown in fig. 4 and 5, the flour 1, the flour 2, the flour 3 … … and the flour n can be collected separately to form the finished flour product, or can be mixed together to form the finished flour product.

The classifying screen used for each screening may have a different mesh size, for example, in the case of a scheme in which three times of grinding and subsequent screening are performed, the classifying screen for the first screening may be 69 mesh, the classifying screen for the second screening may be 76 mesh, and the classifying screen for the third screening may be 91 mesh; in the case of a scheme in which four grinding and subsequent sifting are performed, the classifying screens for four sifting may be: 69 meshes, 76 meshes, 91 meshes and 91 meshes.

The mesh of the classifying screen of the next screening can be larger than that of the classifying screen of the previous screening, so that the flour with smaller granularity can be screened step by step.

According to the invention, qualified fine powder can be separated out in time through the combination of continuous vibration grinding and grading screening, so that over-crushing is avoided, the system efficiency is improved, and the energy consumption is reduced; and moreover, with the system efficiency as a target, the combined relation of crushing and screening is researched, the reasonable particle size distribution and the screening time before screening after crushing are searched, and the system design is carried out by taking the reasonable particle size distribution and the screening time as basic parameters, so that the aim of high efficiency and reasonability is fulfilled.

The damage degree of the starch is controlled through reasonable grinding and screening cooperation (namely, the cooperation of the grinding degree of the vibration grinding and the screening fineness), the lower the grinding degree of the vibration grinding and the coarser the screening fineness are, the lower the damage degree of the starch is, the times of grinding and subsequent screening carried out on the process can be correspondingly increased, and vice versa.

As shown in fig. 6, the oversize material obtained by vibrating and grinding the flour raw material is fed into the vibratory grinding unit again to form the next oversize material and undersize material, the oversize material obtained by each screening is fed as a raw material into the vibratory grinding unit to be ground and re-screened a plurality of times, and the process of each re-grinding and re-screening is a process of grinding and screening the oversize material obtained by the previous screening.

Adjusting the grinding time of each vibration grinding and the stress of the grinding cylinder, such as amplitude and vibration frequency, so that undersize materials formed after the flour raw materials are subjected to primary grinding and screening by a grading screen are wheat core powder; feeding the oversize material subjected to the first screening into another vibration grinding unit 10, and grinding for the second time and screening by a grading screen to form undersize material which is endosperm powder; and (3) putting the oversize material sieved for the second time into a second vibration grinding unit 10, putting the undersize material formed after the third grinding and the screening by a grading sieve into the vibration grinding unit 10, taking the oversize material sieved for the (n-1) th time into endosperm flour … …, and putting the undersize material formed after the nth grinding and the screening by the grading sieve into an endosperm flour finished product, wherein the oversize material formed by the current screening is bran.

In the case of flour materials other than wheat, such as rice, a first flour product corresponding to a wheat core flour and a second flour product corresponding to an endosperm flour can be formed by the above-described method, and flour products corresponding to a fine bran whole wheat flour (described in detail below) can be obtained by directly mixing undersize materials formed by respective siftings.

The endosperm flour may be sieved using a finer mesh classifying screen, while the wheat core flour may be sieved using a coarser mesh classifying screen. The wheat core powder is mixed with endosperm powder with slightly poor gluten quality to form common flour, and the proportion of the wheat core powder in the common flour is equivalent to that of the wheat core in the wheat grains.

In the scheme, in the first grinding and subsequent screening, the wheat is put into a grinding drum, the integrity of wheat grains is damaged after the wheat is subjected to instantaneous high-speed force, the wheat core part with the most loose structure is preferentially refined, and the wheat core part in endosperm can be separated through screening.

In the second and subsequent grinding and subsequent sieving, the remaining grains with the wheat core removed are further subjected to vibration grinding, the endosperm part with better grindability is preferentially refined, and the flour with refined endosperm in the first stage can be separated from the skin layer by sieving.

The scheme realizes the following aims: refining wheat core part (endosperm powder with good gluten quality), refining endosperm part with slightly poor gluten quality, and separating cortex.

The flour production process has the advantages of enhanced fluidization capability and lower crushing temperature, and selective crushing is realized due to the enhanced fluidization capability, the lower crushing temperature and the explosion effect, so that the flour production process does not need complex processes of loosening, cleaning and the like in the traditional process, and the wheat core flour is firstly produced in the process and is produced at one time, so that the excessive crushing is avoided, and the damage to the gluten is small.

As shown in fig. 7, the grinding time and the stress of the grinding cylinder of each vibration grinding can be adjusted to make the undersize material of the first screening and the undersize material of the second screening both be wheat core powder, the two materials can be mixed to form a wheat core powder finished product, or the wheat core powder finished product can be formed separately, and the undersize material of each screening after the third time is general endosperm flour.

In a further approach, bran and flour may be mixed to obtain a coarse bran whole meal, i.e., a whole meal comprising flakes of bran.

As shown in fig. 8, bran may be fed into the vibratory grinding unit 10 to grind and then sift the bran to obtain an oversize bran material and an undersize bran material, the oversize bran material may be fed into the vibratory grinding unit again to form a next oversize bran material and undersize bran material, and the oversize bran materials obtained from each sifting may be fed into the vibratory grinding unit to be reground and rescreened a plurality of times. Each regrinding and rescreening process is a process of grinding and sifting the oversize bran material obtained from the previous sifting.

Undersize materials including fine bran products can be obtained by screening through adjusting the grinding time of the vibration grinding, the vibration frequency of the grinding cylinder and the mesh size of the classifying screen, oversize materials are put into the vibration grinding unit 10 to be continuously ground and screened until oversize materials are not screened out after grinding, and undersize materials obtained by screening after grinding bran are mixed to form the fine bran products.

The scheme realizes crushing (namely vibration grinding) through high-frequency vibration, and realizes staged refining by utilizing the characteristic of fragility of different parts of wheat grains, namely the endosperm part and the bran part can be pulverized in stages.

As shown in fig. 9, the flour and the fine bran product may be mixed to form a fine bran whole wheat flour, i.e., a flour comprising powdered bran.

As mentioned above, the production process provided by the invention can also be used for producing whole wheat flour, and the whole wheat flour produced by adopting the process has the following advantages:

in the aspect of optimizing the fineness of the non-endosperm part, the good taste requirement is directly related to the fineness and the particle property, the fineness of the non-endosperm part in the scheme is based on that the non-endosperm part completely passes through the sieve mesh CQ16, preferably the sieve mesh CQ20, further preferably the sieve mesh CQ27, further preferably the sieve mesh CB30, and further preferably the sieve mesh CB36, so that the prepared steamed bread can not see the bran particles by naked eyes, and has no slag particle taste.

In the aspect of obtaining good fiber taste, the high-frequency vibration is used for crushing, the high impact frequency is very easy to realize the fatigue of the fiber material, and once the fatigue period is crossed, the fiber strength is immediately reduced, so that the fiber material is easy to form isovolumetric particles, and the contribution to the taste is very large. For bread, biscuits and the like characterized by western-style pastries, the bran fiber may remain in a coarse particle state. Different from other stress forms, the fibers generate cracks under the condition of high-frequency vibration, once the fibers absorb water in the application process (dough kneading), the fibers expand, and the viscosity state in the dough kneading process is just suitable for dispersing the fibers with the cracks, so that more refined fiber particles are formed, and the palatability is improved.

In the aspect of protecting starch particles, instantaneous high pressure is applied to endosperm through the control of water and the parameter control of a vibration mill, and the instantaneous explosion effect formed by the internal stress rebound of starch particle clusters in the endosperm is utilized to automatically break starch particles, so that the stress form of the starch particle clusters is far superior to that of the traditional roller grinding, the starch damage degree is lower, the whole wheat steamed bun is beneficial to fermentation, the mouthfeel is smooth and non-sticky, and the mouthfeel and texture of the prepared whole wheat steamed bun are not inferior to those of the common steamed bun.

In the aspect of stabilizing non-endosperm parts, the production process can realize the precise composite stabilization of micro-particles, namely, the grains themselves contain natural antioxidant/preservative including phytic acid to protect unsaturated fat and other unstable components, thereby realizing the stabilization of whole wheat.

The safe endosperm part is taken out in advance in the previous production stage, and the materials including the unsaturated oil and fat to be protected, the enzyme and the protective agent phytic acid are continuously treated in the later production stage.

The wheat germ is the most nutrient part in the wheat grain, is protected by the cortex in a natural state, has no damaged cell wall, and can keep relatively stable after being stored for a long time.

The phytase is the first line of defense for wheat seed germination unlocking, once the phytase is activated by moisture, the internal phytic acid is hydrolyzed, and other active enzymes start to form effective activity by water. Existing roller milling strips the wheat kernels during the initial milling process and scrapes off the endosperm particles, leaving the bran intact as much as possible for subsequent separate processing. In order to realize the integrity of the bran, the wheat is moistened in advance, and the bran absorbs water and is softened. The process of roll milling is exposed to air and the material temperature is relatively higher than ambient temperature.

The waxy layer of wheat is opened, phytase can be activated under the conditions of water, air and temperature, phytic acid is hydrolyzed, the enzyme system is unprotected, namely the self germination system of wheat is quickly activated, lipase and lipoxygenase are activated to take effect, and hydrolysis and oxidation reaction of fat begin. Under the condition, the materials are stabilized in the modes of microwave, hydrothermal reaction, acid protection and the like, and peculiar smell in the materials is difficult to avoid.

The invention prevents the activation of the activity of enzyme (such as phytase), the concrete proposal can be that the water contact is avoided in the production process, for example, the external water addition and the condensed water generation are avoided, and the proposal for avoiding the external water addition is that, for example, the wheat wetting is not carried out, and the water is prevented from permeating into the cortex; the scheme for avoiding the generation of the condensed water is to prevent the grinding temperature from being too high, for example, by controlling the grinding temperature, so as to avoid the moisture of the grains from evaporating and condensing again when meeting the cold.

While avoiding activation including, but not limited to, lipase, lipoxygenase (also known as lipoxygenase), both of which are targeted control points for stabilization. As with phytase inhibition, enzyme activity is inhibited by avoiding moisture and temperature. Meanwhile, phytic acid is also an important link, so that not only is the activity of enzyme inhibited, but also the activity of microorganisms can be inhibited, the oxidation of germs is avoided, and the stabilization of whole grains is realized. In addition, the activity of other enzymes is inhibited by adopting the scheme.

In addition, the invention adopts a fine particle precise composite stabilizing method: when the skin layer fibers are refined by adopting vibration grinding, more phytic acid can be liberated by breaking cell walls; meanwhile, unsaturated grease of the germ is extruded out of oil bubbles and is adsorbed by cellulose components; because the compression type crushing force of the grinding process is favorable for discharging gas in and among cells, the phytic acid is coated on the surface of the fiber with higher probability, the secondary distribution of the phytic acid is realized, and the unsaturated grease adsorbed on the cellulose can be protected. In addition, the active enzyme enclosed in the cortex and embryo has the opportunity to be liberated and protected after attachment by contact with phytic acid. These processes (including the process of cell wall breaking followed by the process of phytic acid protection) can be considered to be performed almost simultaneously.

Compared with whole wheat flour in the prior art, the whole wheat flour does not need curing to inactivate enzyme, is low in cost, and can be stored for one year at normal temperature since the materials are isolated from external oxygen in the process from the production process to the packaging completion. Furthermore, in the production process of the present invention, the dried flour raw material is fed into the vibratory grinding unit, and a wheat wetting process is not required.

In the aspect of solid emulsification, proteins in non-endosperm parts can also participate in the stabilizing process, and the hydrophilic/lipophilic characteristics of the proteins help to complete protection so as to eliminate interference of grease. Once secondary protection of phytic acid has been established, stabilization is complete. The advantage of the large core technology of the invention is the stabilization of the self-recombination of the components.

The invention realizes a complete method, which is established on the level of the current technology and equipment, completes the preparation on the basis of preserving all the due components of the whole wheat flour, and realizes good particle size distribution and the due wheat flavor and taste. The invention takes whole wheat flour as a target product, applies unique self-selection crushing and efficiency advantages of vibration grinding, directly uses wheat as a raw material and adopts a short process to crush whole components.

The vibratory grinding unit is fully enclosed and/or the production system is fully enclosed to avoid air contact to reduce the chance of oxidation. On the premise of reaching a good quality guarantee period, the enzyme is cured/inactivated without using additives, other hydrothermal methods and the like, and can be stored for one year at normal temperature.

When the method is adopted to crush the fibrous materials, the tissue structure and the fibers are easy to damage due to the strong compression tearing acting force, so that the moisture (including crystal water), oil, volatile matters and air in the tissue structure are extruded out (the oxidation probability of germs is reduced), the internal porosity of the tissue is reduced, and the compactness of the materials is increased.

Because the substances in the tissue structure are extruded and adsorbed on the surface of the tissue fragments, the viscosity of the particles is increased, the particles are continuously kneaded and torn under the action of strong compression tearing force, the substances adsorbed on the surface of the tissue structure mutually migrate, and the oily components and the aqueous components are promoted to form an emulsified combination under the action of a biosurfactant (generally, the biological tissue contains substances with surface activity, such as saponin, protein and the like), which is called as solid emulsification.

At the same time of the action, along with the continuous damage and thinning of the tissue structure in the crushing process, under the action of compression, kneading and tearing, through the viscosity action of the migrating substances in the tissue, the thinned different tissue structure fragments continuously form a new combination, which is called as 'precise compounding'.

Phytic acid is the most popular novel food preservative, antioxidant and antistaling agent in the market at present, and the wheat is reported to contain 0.673 percent of phytic acid. The phytic acid also has antioxidant synergist effect in whole wheat flour.

Through the specific fine particle precise complexing effect of vibration grinding, phytic acid in the aleurone layer is dissociated and uniformly dispersed in whole wheat flour particles while the wheat germ is crushed, so that the protection of wheat germ components is realized by effectively utilizing the anticorrosive and antioxidant effects of the phytic acid, the activities of microorganisms and enzymes in the whole wheat flour are inhibited, and the stabilization is realized. Compared with the prior art, the method for extracting the non-endosperm part by adopting the dry heating method, the wet heating method, the microwave method, the extrusion method, the infrared baking method, the gamma irradiation method, the acid protection and the like has more practical application value.

The secondary distribution of the phytic acid in the whole wheat flour effectively inhibits the activity of enzymes carried by wheat, more importantly inhibits the activity of enzymes such as lipase and lipoxygenase (super-oxidase) which promote fat oxidation/rancidity, and the secondary distribution of the phytic acid in the whole wheat flour is taken as the most important stabilizing means to further realize a unique stabilizing combination method by combining with the protection of inert gas (such as nitrogen). This is also one of the technical cores of the present invention.

The invention adopts a full-closed flow from the beginning of grinding to the packaging to obtain a finished product, has low consumption of nitrogen and effectively prevents unsaturated fatty acid of the germ from being oxidized in the production process. The mode also has practical significance for the storage of the packaged finished products, and the packaging bag is filled with nitrogen, so that the oxidation of germs is avoided, and insects and mould fungi can be avoided. Wheat contains only a small amount of oxygen, which is consumed in the storage process in the previous period through the respiration of the flour.

Experiments have proved that: the whole wheat flour prepared by the method is stored for more than one year under the condition of room temperature (or normal temperature) in common packages, and the signs of rancidity and oxidation do not appear.

The package used in the invention is a sealed package, and a multi-layer paper bag (such as three layers of paper separated by one or two layers of films) or a plastic film bag can be selected. The packaging machine is hermetically connected with the finished product bin in a sealed pipeline mode, and the packaging machine preferably selects a valve bag and self-made bag equipment to ensure that the valve bag and the self-made bag are not contacted with the outside air as far as possible. The packaging material should have light-blocking properties to reduce the chance of photosensitive oxidation of the fat.

Due to secondary protection caused by phytic acid, the whole wheat flour is unpacked within the shelf life and can be stored for 1-3 months (time difference is related to temperature, humidity, illumination and the like) without flavor change at normal temperature.

The whole wheat flour prepared by the process has a fatty acid value (calculated by wet basis) (calculated by KOH) of 20-40 mg/100g, and the industrial standard of the whole wheat flour is less than 116mg/100 g.

During the grinding process, the high-frequency compression grinding alternating acting force of the vibration grinding main machine has a breathing effect, original air in grains can be discharged, inert gas (nitrogen) in the system can permeate into the interior of the grains and be adsorbed on the surfaces of the grains, and oxygen in the whole wheat flour grains and around the whole wheat flour grains is partially or completely replaced by the inert gas, so that the direct element of oxidation, namely oxygen, is effectively avoided, and the further synergistic promotion effect is generated on the stabilization of germs.

Alkylresorcinols (ARs) are a particular class of phenolic lipids found in large amounts in wheat and rye bran. It, alpha-tocopherol, anthocyanin, SOD (superoxide dismutase) and the like belong to natural antioxidants. After the cell tissue structure is destroyed through vibration grinding, the components in the cell tissue are released, and due to the precise compound effect of the micro-particles of the vibration grinding unit, the natural antioxidants are distributed secondarily, and good synergistic protection is realized on the easily oxidized components in the whole wheat flour. Taking the alkyl resorcinol with amphipathy as an example, the method is helpful for realizing solid emulsification, improves the better contact probability of the protective component and the protected component, and further improves the effect of fine particle precise composite stabilization.

The phytase contained in the whole wheat flour can hydrolyze phytic acid in the dough fermentation and curing processes, so as to release the preservative effect and lock the nutrient components, namely self-unlocking (preservative release).

There are indications in the french national project of research: phytic acid (phytic acid) is mainly enriched in aleurone layer cell tissues. 10% to 15% of the total phytic acid present in the embryo. This is different from the conventional idea that phytic acid mainly exists in the cortex, but in practical application, aleurone layer, cortex and wheat germ enter wheat bran together, so the results are not different in principle. The key corresponding to the phytic acid, the distribution of the phytase in the wheat grains is as follows: 39.5% of aleurone layer, 34.1% of endosperm and 15.3% of scutellum (cotyledon).

The grains have the capability of germination, contain various enzymes, and can be bred by applying self nutrition and energy through enzymatic reaction under the condition (proper water, temperature and air). Due to the unique process conditions of the method, the secondary 'sealing' of the enzyme carried by the grains can be realized, namely, the enzyme is not damaged as much as possible and the activity of the enzyme is inhibited, which radically inhibits the enzymatic oxidation effect of the germ, and particularly, the active ingredients are protected by keeping the material at low temperature, protecting the material with inert gas (such as nitrogen) and precisely compounding fine particles with phytic acid. This is also the core mechanism of the present invention for germ stabilization. The secondary 'sealing' of the enzyme is a necessary condition for realizing the self-unlocking (the phytic acid is hydrolyzed by the phytase carried by the whole wheat flour) of the grains in the application process (water is added for mixing flour).

And (3) secondary sealing of the enzyme is realized, and the enzyme is prevented from contacting water in the milling process if the enzyme is prevented from being activated. The whole wheat flour production process does not need the traditional procedure of adding water to moisten wheat, and the cleaning process can adopt dry cleaning in an enhanced mode.

Phytic acid is uniformly distributed in bran and is a natural preservative, and once water is available and invades through a waxy surface layer, the inherent phytase starts to be activated, the phytic acid (reaction substrate) is also wetted, and the phytic acid is hydrolyzed by the phytase when the temperature is proper. Upon completion of this process, the enzymes originally inhibited by phytic acid in the grain are replenished with water, i.e., activated, and the biochemical reaction of the grain begins (germination).

In summary, the flour production process provided by the present invention has the following aspects in terms of stabilization:

firstly, the phytic acid (shield) carried by the grains is used for inhibiting the activity of enzymes in the grains, so that the shelf life is prolonged, and the self-protection is realized. When the phytase is used, water is added for kneading, and phytase (lance) is activated, so that phytic acid is hydrolyzed, and self-unlocking is realized.

Secondly, self-protection is realized, activation of phytase is avoided, and activation conditions are controlled: water, temperature.

Thirdly, the effective application of the phytic acid: both the protector (phytic acid) and the protected body (various enzymes) are concentrated in bran (containing embryo). The technical scheme of the patent can simply and clearly separate the endosperm part from the bran in the early stage of flour making, and the endosperm part (flour) is not stained with more bran and/or germ like a common flour process. In fact, the endosperm flour of the traditional flour process, due to moisture, temperature and the large amount of external displaced air, has already started the oxidation process of the fat mixed in the endosperm flour, and since the enzymes are not consumed by the reaction under normal conditions, the fatty acid value of the whole grain flour is high even after the thermal reaction of the bran is completed. According to the Chinese industry standard, the fatty acid value takes 116 as a critical point, and the detection value of the invention is 33.2.

The following table 1 is a table of the test data for flours produced according to the flour production process of the present invention:

TABLE 1

In the patent, after endosperm flour is preferentially taken out, the rest bran and germ are basically remained, and relatively speaking, the natural preservative/enzyme inhibitor (phytic acid) and enzyme are both in a high-concentration state, so that the phytic acid is easier to inhibit the enzyme.

In the whole production process, the materials are controlled to be at a lower temperature, water is not added, and oxygen deficiency is realized in a sealed space, so that the activation of the enzyme can be effectively avoided, and meanwhile, the activity of the enzyme is inhibited through the precise compounding of the microparticles and the secondary protection of the phytic acid. This method is called "fine particle precision composite stabilization", a stabilization method which is quite different from the conventional technique.

Experiments prove that the whole grain powder prepared by the method has no rancidity after being stored for one year under the condition of normal-temperature sealed storage.

In the patent, after the endosperm flour is preferentially taken out, the rest is basically bran and embryo, and relatively speaking, the natural preservative/enzyme inhibitor (phytic acid) and the enzyme are both in a high-concentration state, so that the phytic acid is easier to inhibit the enzyme.

The method disclosed by the patent is low in temperature, free of water and poor in oxygen realized by a sealed space in the whole production process, the activation of the enzyme is effectively avoided, and meanwhile, the activity of the enzyme is inhibited through the fine particle precise compounding and the secondary protection of the phytic acid. This method, which we call "fine particle precision composite stabilization", is a stabilization method that is quite different from the conventional technique.

The whole grain powder prepared by the method is stored for one year without rancidity under the sealed storage condition at normal temperature.

Further, the gas is introduced to improve the fluidization state of the material, which results in more chance of oxidation. Still further, an inert gas is introduced.

Experiments prove that after the package of the whole wheat flour is opened within the shelf life, the product can be placed for 1-3 months (the time difference is related to temperature, humidity, illumination and the like) at normal temperature without flavor change. Therefore, the activity of lipase and lipoxygenase is effectively inhibited due to the secondary protection formed by phytic acid under the condition that the nitrogen protection is lost, and the stabilization, namely the precise compound stabilization of the microparticles, is realized.

The whole wheat produced by the process has the following health advantages:

in order to avoid the oxidation of germs, the grains have a self-protection system, and the surface layer (from seed coat to aleurone layer) contains various natural antioxidants (phenolic acid, anthocyanin, SOD and the like). The aleurone layer contains protein, B vitamins, minerals and a small amount of cellulose. From the perspective of nutrition, the aleurone is a part of wheat grains which is rich in nutritional ingredients, particularly B vitamins are necessary for human bodies, and beriberi can be caused if the B vitamins are deficient. These valuable cells are surrounded by thick cell walls and cannot be digested and absorbed by humans without destroying the cell walls. The invention adopts a vibration grinding mode, and the compression crushing stress mode can effectively destroy cell walls and cell tissues and release valuable substances. Because the technical scheme realizes the sealing storage of the enzyme system and avoids the enzyme activation in the production process, the original nutrient components of the grains can be effectively protected. Also included are protection of the non-starch polysaccharides from hydrolysis by endogenous enzymes of the grain.

The cell wall of the grains is mainly composed of non-starch polysaccharide. The non-starch polysaccharides in wheat mainly comprise Arabinoxylan (AX), beta-glucan and small amounts of arabinogalactan and glucomannan, wherein the highest content is arabinoxylan. The method of vibration grinding can break cell walls, the water-soluble polysaccharide can be liberated, and under non-fermentation conditions (such as noodles), the water-soluble polysaccharide (hemicellulose) preferentially holds water to form a high-viscosity colloid to wrap starch. Since the hemicellulose is not hydrolyzed by human digestive juice, amylase in human body is prevented from contacting reaction substrate (starch), thereby forming starch slow release. This is of great significance to the diabetic.

After the water-insoluble fibers are refined by the method, a multi-particle fiber brush is formed, so that the small intestine can be effectively stimulated to promote peristalsis to improve constipation, and grease (including redundant cholesterol) can be adsorbed. This is most evident in noodle products. The noodles entering gastrointestinal tract show needle-like/sheet-like fiber after surface starch corrosion inhibition, and stimulate duodenal mucosa and intestinal villus while adsorbing oil and fat with the function similar to fiber brush. The secretion of digestive glands is wakened through stimulation, the blood circulation of a digestive tract is accelerated, the intestinal peristalsis is promoted, defecation is accelerated, the emptying of the intestinal tract is accelerated, the abdominal cavity pressure is reduced, the external pressure of digestive juice extruded by a gallbladder and a pancreas is reduced, and the secretion of the digestive juice including insulin is promoted.

Most of the current studies on phytic acid, non-starch polysaccharides, are directed to feed or beer. The phytase is used as feed, and is used for hydrolyzing phytic acid to facilitate the absorption of phosphorus and other trace elements; it is desirable to hydrolyze hemicellulose with xylanases to improve digestion and absorption of the enzymes into the feed. The whole aim is to improve the feed conversion ratio and ensure that the livestock can grow meat quickly and can be slaughtered.

And vice versa for humans. In the current living environment, people need balanced nutrition and do not need to grow meat quickly, and the small intestine of people needs hemicellulose to help form a good microbial environment. People domesticate grains for ten thousand years, and people have gene requirements on grains, especially people in farming culture systems (Chinese people). The large-area diabetes (the incidence rate is 11.7 percent and the pre-diabetes is 50 percent) in China in recent ten years, 1 million people suffer from cancer every day, which is not a medical problem, and the direct relationship is provided between the wheat core powder which is fully popularized to date ten years ago and the over-fine staple food of five throw rice. In recent ten years, the rapid change of the dietary state can continuously obtain nutrients from bran and germ every meal, and the nutrients disappear in a whole time in several years. This is a catastrophic impact on the health of chinese people, especially the flooding of diabetes. The current development trend of data predicts that the number of diabetes patients in China will reach 6 hundred million by 2035.

People are animals domesticated by nature, need balanced nutrition, and for an agro-farming culture system with extremely high dependence on grain staple food, the balance of the body can be realized only by returning to the natural balanced nutrition intake, so that the basic elements of health can be achieved.

Under the conditions of the product technology with the staple whole wheat and the environment with wide health appeal of the current market, the whole wheat product which meets the Chinese diet characteristics is produced in a low-cost industrialized mode, not only meets the health concept of the current whole wheat food, but also directly increases the yield by 30 percent compared with the traditional flour production mode. The method has great significance for guaranteeing food supply and health of the whole people.

As shown in fig. 10, the present invention also provides a recycling flour production process which may include two stages, a first stage producing flour and a second stage producing fine bran products, after completion of the first stage production task, the bran obtained from the screening being fed multiple times to a vibratory grinding unit for re-grinding and re-screening, and when the oversize material is no longer screened, the entire undersize material, i.e., the fine bran products, obtained from the second stage are collected to form a finished fine bran product.

The parameters such as vibration acceleration, vibration displacement, multi-temperature (such as raw material temperature, finished product temperature, water jacket temperature and the like), gas pressure, power, material flow, bin weight and the like can be monitored in real time in the flour production process, and the production running state can be monitored in real time through monitoring pictures, trends, alarm conditions and the like of a host machine vibration state diagram, a power system running diagram, a material running diagram, a cold water system running diagram, a safe air supply system running diagram, an oxygen and nitrogen gas system running diagram and the like.

The vibrating mill can be connected with the feeding machine, so that flour raw materials enter the vibrating mill from the feeding machine, gas can be introduced between the feeding machine and the vibrating mill, the feeding machine (such as a star-shaped feeding machine) can have certain gas locking capacity, the gas penetrates through the milling barrel, the flowing direction and the flowing speed of the gas are reasonably set, the materials can be automatically classified in a fluidization state, and fine particles are discharged preferentially. The gas introduced may be compressed air or an inert gas, including but not limited to nitrogen, carbon dioxide, argon, etc., and combinations thereof, such as O ₂ +CO ₂ +N ₂ ，N ₂ +CO ₂ ，O ₂ +CO ₂ 。

It will be appreciated that the inert gas may contain a certain amount of oxygen, but the oxygen content is not preferably too high, preferably not more than 15% of the total gas.

In the present invention, the abrasive body filling rate may be: 30-95% (volume filling rate), preferably 40-80%, and preferably 50-70%; the grinding time for each vibration grinding can be: 1-30 minutes; the mesh of the classifying screen is at least mesh CQ 16.

The invention adopts a vibration grinding method, and the vibration frequency of the grinding cylinder is controlled to be 8-50 Hz under the condition that the power frequency is 50Hz (the vibration frequency can be correspondingly changed under the condition of other power frequencies such as 60 Hz), the optimized frequency is 10-30 Hz, the optimized frequency is 12-26 Hz, and the optimized frequency is 12-13 Hz, 15-17 Hz or 23-26 Hz. In another example, under the condition that the power frequency is 50Hz, the vibration frequency can be 10-31 Hz, preferably 12-26 Hz, and preferably 12-15 Hz, 16-20 Hz or 24-29 Hz.

The amplitude (single amplitude) of the grinding cylinder can be 2-9 mm, and is optimized to be 3-5 mm, 5-8 mm or 4-6 mm. The vibration mode of the grinding cylinder can be circular vibration or elliptical vibration.

The oxygen content in the milling drum is not more than 15%, more preferably not more than 10%, more preferably not more than 5%, more preferably not more than 3%, more preferably not more than 1%.

The invention is also suitable for preparing oriental characteristic food materials, namely rice flour and glutinous rice flour, which comprise different varieties of white, purple, black and the like. Under the condition of dry production process, the effect of wet grinding is achieved, and the wet grinding is free from water pollution and does not need drying.

The method can realize the preparation of low-gluten flour, namely, the strengthened grinding realizes the gluten fracture and reduces the gluten degree of the flour, and is a scheme for preparing the flour with relatively low gluten degree by adopting relatively strong wheat as a raw material.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice in the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (14)

1. A flour production process is characterized by comprising the following steps:

preparing a dried flour raw material;

feeding the dried flour raw material into a vibration grinding unit comprising a vibration mill and a grading sieve without wheat wetting, grinding and screening the dried flour raw material by the vibration mill and the grading sieve to form undersize materials in multiple stages, and automatically disintegrating starch granules by utilizing an instantaneous explosion effect formed by the internal stress rebound of starch granule clusters in endosperm;

obtaining products formed by crushing parts with different porosities in the flour raw material from the undersize materials in different stages,

the flour comprises the following raw materials: the content of the wheat is as follows,

the flour raw material is ground and sieved by the vibration mill and the classifying screen to form an oversize material, bran is obtained from the oversize material, and flour is obtained from the undersize material, wherein the steps of loosening and cleaning flour are not included.

2. Process for the production of flour according to claim 1,

feeding the bran into a first vibratory grinding unit to obtain an oversize bran material and an undersize bran material, and feeding the oversize bran material into the first vibratory grinding unit or another vibratory grinding unit to obtain a next oversize bran material and an undersize bran material;

when the oversize bran material is no longer screened, the whole undersize bran material is collected to obtain a fine bran product.

3. A flour production process according to claim 2, characterized in that the flour and the fine bran product are mixed to obtain a fine bran whole wheat flour.

4. Flour production process according to claim 1,

grinding and screening the flour raw material by the vibration mill and the classifying screen to form oversize materials corresponding to undersize materials in multiple stages, and feeding the oversize materials into the same vibration grinding unit or different vibration grinding units to form oversize materials and undersize materials in the next stage;

the grinding time and the force of the vibration mill of the vibration grinding unit are adjusted to obtain the corncob meal first through the undersize material previously screened and to obtain the endosperm meal having a gluten quality slightly inferior to that of the corncob meal through the undersize material screened later.

5. A flour production process according to claim 1, characterized in that the flour and the bran are mixed together to obtain a coarse bran whole wheat flour.

6. The flour production process according to claim 1, wherein the vibrating grinding unit is fed with gas which is circulated from a feed inlet to a discharge outlet of the vibrating mill, and the gas passes through the vibrating mill.

7. A flour production process according to claim 3, wherein: the vibration frequency of the vibration mill is 8HZ to 50HZ, the amplitude of the vibration mill is 2mm to 9mm, and the vibration acceleration of the vibration mill is 2g to 10g, so that the wheat bran micro-particles are precisely compounded.

8. A flour production process according to claim 3, characterized in that the bran contains phytic acid and phytase, the bran is fed into the vibratory grinding unit to precision-complex the micro-particles of bran and put the phytase in an inhibited state, and the phytic acid is released from the bran and redistributed in the fine bran whole wheat flour to achieve phytic acid secondary protection.

9. A flour production process according to claim 3 wherein the bran contains phytic acid and phytase, the undersize material comprises flour and a fine bran product, the flour and the fine bran product being obtained separately such that substantially all of the phytic acid and phytase are in the fine bran product.

10. A flour production process according to claim 3, wherein the bran contains phytase, lipase and lipoxygenase, the temperature of the ground material is controlled not to exceed 40 degrees celsius and/or the dry flour feedstock is fed to the vibratory grinding unit to inhibit the activity of phytase and/or lipase and/or lipoxygenase.

11. A process for producing flour as claimed in claim 3, wherein the bran contains lipoxygenase, and wherein the inert gas is injected into the barrel of the vibratory mill, the fat in the flour feedstock is substantially free of oxygen, and the lipoxygenase is in an inhibited state.

12. A wheat flour production system comprising a vibratory grinding unit, the vibratory grinding unit comprising:

the vibration mill comprises a milling cylinder and milling bodies, wherein the milling cylinder performs circular vibration, and a plurality of milling bodies are freely placed in the milling cylinder;

a classifying screen connected to a discharge port of the grinding drum to screen the ground flour raw material;

and under the condition of not moistening wheat, sequentially grinding the dried flour raw material by the vibration mill and screening by the grading sieve to form undersize materials in different stages, automatically disintegrating starch granules by utilizing an instantaneous explosion effect formed by the internal stress rebound of starch particle groups in endosperm, and obtaining a product formed by crushing various parts with different looseness in the flour raw material from the undersize materials in different stages.

13. The wheat flour production system as claimed in claim 12, wherein the outer peripheral wall of the grinding drum is sheathed with a cooling water jacket filled with flowing cooling water not higher than room temperature.

14. A wheat flour production system as claimed in claim 12 in which the grinding drum is filled with an inert gas.

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