Method and apparatus for grinding grains

Abstract

The invention relates to a machine for grinding grains (1), said machine comprising one or more crushing devices (2), each crushing device comprising a first comb roller (3) rotating about a first axis of rotation (A1) and a second comb roller (4) rotating about a second axis of rotation (A2), the first comb roller comprising a plurality of first tooth (5) radii around the axis of rotation (A1), the second comb roller comprising a plurality of second tooth (6) radii around the axis of rotation (A2), and the second comb roller comprising a plurality of second tooth (7) radii around the axis of rotation (A2). The second combing roller comprises a plurality of second tooth (6) radii about a second axis of rotation (A2), the first tooth radius and the second tooth radius having a complementary overlapping shape, the gap width (W) between the teeth of the rollers being greater than 0, the first combing roller (3) and the second combing roller (4) being driven in rotation by one or more motors, the motor is configured to drive the first tooth at a tangential velocity (V1) greater than a tangential velocity (V2) of the second tooth.

Description

[0001] The present invention relates to a method for grinding vegetable grains, in particular cereal grains, for example for the preparation of bread. The present invention also relates to the preparation of bread using the ground cereal grains.

[0002] In the process of grinding cereal grains to produce flour for making bread, pastries and other foods prepared with cereal flour, millstones are used to break the cereal grains into small pieces by crushing and friction. The shearing and heating action of the flour particles causes most of the cells on the surface of the particles to rupture and thus die.

[0003] In many traditional methods, starch is separated from the germ and pericarp. The starch is ground into fine particles to form white flour, and in the case of whole wheat flour, some or all of the pericarp particles, protein matrix particles, and sometimes germ particles are added.

[0004] Since the flour will be cooked to produce bread or other flour-containing foods, it is not important to maintain the integrity of the cells on the surface of the flour particles. On the contrary, it is believed that the more living cells there are, the higher the activity, which may lead to a shorter shelf life of the flour. However, the method of heating the particles during the grain milling process also leads to the destruction of some heat-sensitive compounds such as polyphenols. Therefore, after adopting the grain milling method, traditional flour will lose some of its taste.

[0005] In the food industry, there is a general desire to improve the taste of products, as well as other factors such as shelf life and ecological balance, which must take into account the entire cycle from the cultivation of the grain to the final consumer product.

[0006] In view of the above, an object of the present invention is to provide an apparatus and method for grinding cereal grains or other cereal grain-like plants (such as chocolate beans, coffee beans and corn kernels) to improve the taste of products such as bread produced using the ground cereal grain flour.

[0007] Flour with a long shelf life is advantageous.

[0008] Advantageously, a method and apparatus for grinding plant grains, such as cereal grains, is provided, which method and apparatus are environmentally friendly.

[0009] Another object of the present invention is to provide bread having a good taste.

[0010] Advantageously, bread is provided that has a good overall ecological balance.

[0011] The objects of the invention are achieved by the independent claims. The dependent claims describe advantageous features of the invention.

[0012] The present invention describes a machine for grinding plant grains (such as grains), the machine comprising one or more crushing devices, the crushing devices comprising a first comb roller rotating around a first rotation axis and a second comb roller rotating around a second rotation axis, the first comb roller comprising a plurality of first tooth radii (radii of first teeth) around the rotation axis (A1), the second comb roller comprising a plurality of second tooth radii around the second rotation axis (A2), the first tooth radii and the second tooth radii having complementary overlapping shapes, the gap width W between the teeth of the rollers being greater than 0, the first comb roller and the second comb roller being driven to rotate by one or more motors, the motors being configured to drive the first teeth at a tangential speed V1 greater than the tangential speed V2 of the second teeth.

[0013] In an advantageous embodiment, the first tooth has a conical shape, the angle (α) of which, seen in section in a radial plane, is in the range of 15 to 45 degrees.

[0014] In an advantageous embodiment, the tops of the teeth have a rounded shape.

[0015] In an advantageous embodiment, the length T1 of the tangent of the first tooth between the leading edge 11 and the trailing edge is greater than the length T2 of the tangent of the second tooth between the leading edge and the trailing edge.

[0016] In an advantageous embodiment, a tangent length ratio T2 / T1 of the second teeth relative to the first teeth is in the range of 0.2 to 0.8.

[0017] In an advantageous embodiment, the first comb roller is configured to rotate at a tangential speed V1 between 1 and 5 times the tangential speed V2 of the second comb roller.

[0018] In an advantageous embodiment, the first tooth of the first comb roller comprises a leading edge which is inclined relative to a radial direction passing through the leading edge base in the rotational direction of the first comb roller.

[0019] In an advantageous embodiment, the inclination angle β1 of the leading edge relative to the radial direction of the first roller is between 5 degrees and 45 degrees, preferably between 10 degrees and 35 degrees.

[0020] In an advantageous embodiment, the second tooth of the second comb roller comprises a trailing edge which is inclined relative to a radial direction passing through the base of the trailing edge in the direction of rotation of the second comb roller.

[0021] In an advantageous embodiment, the inclination angle of the trailing edge relative to the radial direction of the second roller is Between 0 degrees and 40 degrees, preferably between 5 degrees and 30 degrees.

[0022] In an advantageous embodiment, the machine comprises a mechanism for adjusting the distance between the first axis of rotation A1 and the second axis of rotation A2 in order to adjust the gap width W between the first roller and the second roller.

[0023] In an advantageous embodiment, the machine comprises a plurality of crushing devices, an upstream crushing device having a larger roller gap width W than a downstream crushing device.

[0024] In an advantageous embodiment, the machine comprises a plurality of crushing devices and a plurality of conveying devices, the conveying devices being configured to convey the grain fragments between the crushing devices and from the last crushing device to an outlet of the machine.

[0025] In an advantageous embodiment, the machine comprises a cabin and a neutral gas (such as nitrogen) source connected to the cabin, the cabin is filled with neutral gas, and the crushing device is arranged in the cabin.

[0026] In an advantageous embodiment, the cabin is sealed so that a negative pressure can be generated in the cabin.

[0027] In an advantageous embodiment, the machine comprises a feed device located at the inlet of the machine, the feed device comprising a metering distributor comprising a splined dispensing roller driven in rotation by the motor of the machine.

[0028] In an advantageous embodiment, the machine comprises at least one drying device placed between the two crushing devices, for example a device for drying the grain fragments by radiant heat and / or ventilation.

[0029] The present invention also describes a method for grinding plant grains (such as grains), which includes the step of crushing the grains between a first tooth and a second tooth, wherein the first tooth and the second tooth are separated by a gap with a width W greater than 0 and less than the average particle size of the grains, and the gap is configured to break the grains or grain fragments into fragments by shearing and folding effects, and most of the crushing surface will not rub against the teeth.

[0030] In an advantageous embodiment, a machine as in the above embodiments is used to break up the grains.

[0031] The present invention also describes a cereal crumb powder obtained by the method according to any of the above embodiments, the cereal crumb powder comprising the following features:

[0032] - average size of the debris: between 90 μm and 5 mm, preferably between 0.1 mm and 2 mm, for example 0.2 mm to 1 mm;

[0033] - Number of intact cells on the crushed surface of the debris, on average: greater than 30%, preferably greater than 40%, for example greater than 50%.

[0034] The present invention also describes a bread comprising the above-mentioned grain crumb flour, wherein the dry weight proportion of the grain crumb flour is 5% to 50% of the total dry weight of flour forming the bread, preferably between 20% and 40%, for example between 25% and 35%.

[0035] The present invention also describes a method for making bread according to the aforementioned embodiment, the method comprising:

[0036] - Wet and scald the crumb powder,

[0037] -Prepare bread dough by adding starch flour to crumb flour in proportion,

[0038] -Bake the bread dough in the oven.

[0039] Further objects and advantages of the present invention will become apparent after reading the following claims and / or the detailed description of embodiments of the invention in relation to the accompanying drawings, in which:

[0040] Figure 1 is a schematic perspective view of an apparatus for grinding grain according to one embodiment of the present invention, with the cabin wall removed to see the interior;

[0041] Figure 2 yes Figure 1 a schematic diagram of a portion of the machine shown, showing the feeding and crushing devices;

[0042] Figure 3 yes Figure 2 The device and the perspective view of the conveying device and the drying device;

[0043] Figure 4a is a schematic perspective view of a first comb roller and a second comb roller of a crushing device according to an embodiment of the present invention;

[0044] Figure 4b is a view along the direction of the rotation axis of the first roller and the second roller;

[0045] Figure 4c yes Figure 4a A top view of a first roller and a second roller;

[0046] Figure 5a is a view along the rotation axis direction of the first comb roller;

[0047] Figure 5b yes Figure 5a a top view of a first roller;

[0048] Figure 5c yes Figure 5a and 5b a cross-sectional view of a first roller;

[0049] Figure 6a is a view along the rotation axis direction of the second comb roller;

[0050] Figure 6b yes Figure 6a a top view of a second roller;

[0051] Figure 6c yes Figure 6a and 6b a cross-sectional view of a second roller;

[0052] Figure 7a is a photograph of grain fragments obtained by the method and apparatus according to the invention;

[0053] Figure 7b is a photographic view of a bread slice made using the crumb flour obtained by the method and apparatus according to the present invention;

[0054] Figure 8 It is a schematic diagram of the known structure of grains (here referring to wheat).

[0055] Referring to the attached drawings, from Figures 1 to 3 Initially, the grain grinder 1 comprises at least one crushing device 2 mounted in a chamber 16 having an inlet 19 and an outlet 20. The grinder may also comprise a neutral gas source (e.g., nitrogen source 17) connected to the chamber 16, the neutral gas source being configured to fill the chamber with neutral gas to avoid or limit oxidation of the crushed grain in the machine. The outlet 20 may comprise a channel or conduit directly connected to a container, bag, or other form of container, where the crushed flour leaving the machine is collected while remaining surrounded by the neutral gas in order to preserve the flour in the container at the end of the filling process.

[0056] The mill further comprises conveying means 26 for conveying the grain fragments from the inlet 19 to the outlet 20 via the one or more crushing means 2. The conveying means 26 may comprise one or more conveyor / vibrating belts, or vibrating pans, such conveying means being known per se.

[0057] The machine 1 preferably comprises a plurality of crushing devices 2 in order to reduce the size of the debris in stages. The crushing devices may be as follows: Figure 2 Place them one after another as shown, or Figure 1 Shown separated by conveying means 26.

[0058] The feed device 21 located at the entrance 19 of the cabin 16 includes a metering distributor 23 for metering the amount of grain introduced into the first crushing device of the machine. The metering distributor 23 can be located below the funnel 22 to guide the grain to the metering distributor 23. In the embodiment shown, the metering distributor 23 includes a distribution roller 24, which includes splines 25, the width and depth of which are adapted to the size and type of grain ground by the machine. When the distribution roller rotates, the splines 25 limit the amount of grain that will be poured into the first crushing device 2, and the rotation speed of the distribution roller 24 is also controlled to adapt the amount of grain provided to the crushing device over time.

[0059] Upstream of the metering distributor 23 and the hopper 22, there may be a conveying device for conveying grain from a grain source.

[0060] The grinding machine 1 may also comprise one or more drying devices 28, which are configured to dry the grain crumbs, in particular during the conveying of the crumbs by the conveying device 26. The drying of the grain crumbs may be carried out between two crushing devices 2 and / or between the last crushing device and the outlet 20. The last crushing device may also be configured to toast the crumbs before they are packaged in a container at the machine outlet 20.

[0061] The crushing device 2 includes a first comb roller 3 and a second comb roller 4. The first comb roller 3 rotates about a rotation axis A1 and is driven by a motor (not shown) configured to rotate the first comb roller at a rotation speed V1, which can be varied depending on the type of grain and the required flow rate. Similarly, the second comb roller 4 is rotatably mounted about a rotation axis A2 parallel to the first rotation axis A1 and is connected to a second motor having a rotation speed V2, which can be varied and controlled independently of the rotation speed V1 of the first comb roller 3. In some embodiments, a single rotating motor can also be connected to the two crushing rollers by a transmission device with a fixed or variable ratio so that the speed of the first roller is different from the speed of the second roller.

[0062] The first comb roller 3 comprises a plurality of first teeth 5 radii arranged in a circle around the rotation axis A1. Adjacent radii of the first teeth are spaced apart by a pitch P. The second comb roller 4 further comprises a plurality of second teeth 6 radii arranged around the rotation axis A2, the second teeth also being spaced apart between adjacent radii by a pitch P. The shapes of the first teeth and tooth grooves and the shapes of the second teeth and tooth grooves are complementary, so that the first teeth and the second teeth can overlap / interlock.

[0063] The first and second teeth each have a conical shape with a rounded top, complementary to the flared shape of the transverse tooth gap with rounded recesses 15 and 16. In a section orthogonal to the axis of rotation, the angle α of the conical shape is preferably between 15 and 55 degrees (15°<α<55°).

[0064] The radii of the rounded corners R1 and R2 are preferably complementary and between 0.5 mm and 2 mm (0.5 mm < R1 < 2 mm and 0.5 mm < R2 < 2 mm).

[0065] In the illustrated embodiment, the maximum diameter D1 of the first roller is the same as or close to the maximum diameter D2 of the second roller, but it is conceivable that the diameter D1 of the first roller is different from the diameter D2 of the second roller.

[0066] The machine comprises an adjustment system (not shown) for adjusting the supports of the first and second rollers of the crushing device to adjust the distance H between the axes of rotation and thus the roller gap width W to correspond to the gap width between the roller teeth.

[0067] When the machine comprises a plurality of crushing devices 2, the roller gap width W downstream of the crushing device is set smaller than the roller gap width W of the crushing device located upstream. Thus, the successive crushing devices reduce the size of the produced flour shreds.

[0068] The first teeth constituting the circumference of the first comb roller 3 each extend in a circular sector between the leading edge 11 and the trailing edge 13 with a tangent length T1. The first teeth are separated from each other by circular spacing sectors with a tangent length E1. The length of the spacing is preferably shorter than the length of the teeth T1>E1.

[0069] For a first roller with a diameter D1 of about 4-20 cm, the tangent length T1 of the first tooth is, for example, about 1-6 cm. The tangent length T1 of the first tooth and the gap length E1 of the first tooth can be different from the tangent length T2 of the second tooth of the second roller and the tangent gap length E2 between the second teeth of the second roller, respectively.

[0070] In an advantageous embodiment, the tangent length T2 of the second teeth of the second roller is smaller than the tangent length T1>T2 of the first teeth of the first roller. Preferably, the ratio T2 / T1 between the tangent length T2 of the second teeth and the tangent length T1 of the first teeth is between 0.2 and 0.8 (0.2<T1 / T2<0.8).

[0071] The leading edge 11 of the first tooth 5 is inclined in the rotational direction relative to the radial direction passing through the minimum radius point of the leading edge (i.e., at the tooth base). In one embodiment, the angle β1 of the leading edge relative to the radial direction (of the first roller) is between 5 degrees and 45 degrees (5°<β1<45°), preferably between 10 degrees and 35 degrees (10°<β1<35°).

[0072] The trailing edge 13 of the second tooth 5 is inclined in the rotational direction relative to the radial direction passing through the point of minimum radius of the trailing edge (i.e. at the tooth base). In one embodiment, the angle of the trailing edge relative to the radial direction (of the first roller) is Between 0 and 40 degrees Preferably between 5 and 30 degrees

[0073] The first roller is driven in rotation at a rotation speed Vr1, resulting in a tangential speed V1 of the first teeth that is greater than the tangential speed V2 of the second teeth of the second roller driven at a rotation speed Vr2, with the result that the leading edge 11 of the first teeth clamps the grain against the trailing edge 14 of the second teeth, taking into account the gap width W separating the rollers 3, 4. The seed wedged between the leading edge 11 of the first tooth 5 and the trailing edge 14 of the second tooth 6 is subjected to shearing, folding and tensile forces. Due to the configuration of the teeth and the gap, these seed-tearing forces have the effect of separating part of the grain into fragments, leaving most of the cells on the shattering surface intact, as there is no direct friction on most of the shattering surface. It is inevitable that some cells will be broken by shearing and friction, especially in the part that is in direct contact with the teeth, but most of the shattering surface will not be in contact with the teeth, and in any case, the friction and shattering forces are much lower than those of conventional grinding stone systems to maintain the integrity of most of the cells in the shattering surface.

[0074] When the grain is broken in a first stage, it is advantageous to dry these fragments in order to improve the quality of the crushing in the subsequent crushing stage, thereby producing smaller fragments. The drying method can be carried out by a drying device 28 arranged between the two crushing devices 2 along the conveying device 26. The drying device can, for example, include a radiant heating body and / or a drying gas and / or hot air sprayed on the passing grain fragments.

[0075] In one embodiment, the cabin 16 can be sealed so that there can be a negative pressure in the cabin. This negative pressure is conducive to faster drying of the debris.

[0076] The rotation of the two rollers 3, 4 so as to have a downward tangential velocity component at the interface between the rollers ensures that the upstream grain or debris passes the interface between the first comb roller 3 and the second comb roller 4. This prevents grain and debris from accumulating above the rollers.

[0077] Angle of the first tooth (of the first roller) The shape of the trailing edge 14, as well as the angle β2 of the second tooth (of the second roller) and the shape of the leading edge 12 are less important than the leading edge of the first tooth and the trailing edge of the second tooth. In one embodiment, the angle of the trailing edge 14 of the first tooth and the leading edge 12 of the second tooth can vary in the direction of rotation, for example between 0° and 40° ( and 0°<β2<40°).

[0078] Since the first roller rotates faster than the second roller, it is advantageous that the tangent length T2 of the circular sector of the second roller's teeth is smaller than the tangent length T1 of the circular sector of the first roller's teeth. This ensures that the leading edge 11 of the first tooth intersects the trailing edge 14 of the second tooth and wedges into the grain to break it.

[0079] In one embodiment, in particular for grinding grain, the radial height hd of the first and second teeth is between 2 mm and 20 mm (2 mm < hd < 20 mm), preferably between 3 mm and 10 mm (3 mm < hd < 10 mm).

[0080] During the breaking process, the grain or grain fragments are retained by the trailing edge 14 of the second comb roller 4, because the second roller rotates slower than the first roller, and the teeth of the first roller catch the grain and fragments as they pass the trailing edge, causing the grain and fragments to break. The grain and fragments driven by the first roller 3 are thrown onto the second roller 4 and then captured by the subsequent teeth during the rotation of the first roller faster than the second roller.

[0081] The grinder may also include a device for separating different sizes of crumbs by using a vibrating screen device having a grid that retains crumbs of a certain size and allows smaller sizes to pass through a conveying or receiving system. The separation of crumb sizes allows for better control of the metering and composition of the crumb flour for subsequent production of bread or other flour-based food products.

[0082] The following table summarizes the preferred value ranges for the parameters of embodiments of the present invention:

[0083]

[0084] Advantageously, the grain crumbs produced by the method of the invention can absorb more water, since the proportion of live cells on the crumb surface is greater than in conventional methods, where the friction and crushing and heating of the friction surface destroy most of the cells. In fact, live cells can accumulate and retain more water than dead cells.

[0085] When making dough, especially bread dough, the grain crumbs ground by the method of the present invention are first wetted to increase the moisture content of the crumb flour, and then cooked to kill the cells when the cells are saturated with water. The scalded crumb flour is then mixed with conventional flour, such as white flour, whose starch and gluten content can make the dough bind.

[0086] Advantageously, the cereal crumb flour produced according to the invention is used to make bread, the cereal crumb flour being mixed with baking white flour in an amount of 5% to 50% by dry weight. White wheat flour for bread has the following typical characteristics: an average particle size of about 90 to 100 microns and a typical moisture content of about 14.5 max%.

[0087] When the ratio of the grain crumb powder prepared by the method of the present invention reaches a specified ratio, the taste and shelf life of the bread will be improved.

[0088] Cereal crumbs such as wheat, rye, spelt, barley, oats, etc. are best prepared by blanching in water at about 90°C, as they absorb more water than traditional starch flours.

[0089] Thus, they expand more and the oxygen released captures different polyphenols and other aromas. For example, when baking bread composed of a greater or lesser amount of this crumb flour according to an embodiment of the invention, the still living cells are neutralized and the resulting bread tastes more natural, thicker and lasts longer.

[0090] The greater the amount of crumb flour in the dough, the less salt is needed and the healthier the bread is for the consumer.

[0091] Example of rye bread

[0092]

[0093] Components:

[0094]

[0095] Crushed rye flour is very advantageous to bakers because it makes the bread heavier (has more water content) with the same amount of flour.

[0096] Examples of spelt or durum wheat bread

[0097]

[0098] Components:

[0099]

[0100] Like cracked rye flour, spelt and durum wheat flours can also be beneficial.

[0101] In both embodiments, the bread is 20 cm to 30 cm long, 7 cm to 10 cm wide and 8 cm to 10 cm high. The air bubbles in the white part of the bread are 2 mm to 5 mm and are intact. Under the action of pressure, they retain all their initial shapes. The crust has become hardened by cooking, with a medium roughness, but is resistant to pressure. Therefore, the bread can be stacked without losing its shape. If the dough is covered with spelt crumbs, the upper crust of the bread will tear during baking, giving it a fresh appearance. The crust is crispy and protects the fragrant inner white part, which does not contain any additives.

[0102] Since the white part of the bread with the crumb flour according to the invention is more moist (amount of water absorbed by the grain crumbs), the back quickly returns to its original shape before compression.

[0103] Photograph of a bread slice according to the second embodiment ( Figure 7b ) shows the brightness of the white portion and the thickness of the protective crust.

[0104] Characteristic example of crushed powder according to one embodiment

[0105] Wheat, spelt and / or rye grains are composed approximately of the following components (see Figure 8 ):

[0106] - 85% of the starch contained in the kernel of the grain;

[0107] -6% bran, which is the protective seed coat of the grain, has no nutritional value, but is useful for intestinal transit;

[0108] -9% protein matrix (aleurone + clear layer + seed coat + germ), containing many vitamins and food supplements that are very useful for human health;

[0109] -at last

[0110] -The germ or embryo, which is the living cell in the grain of a plant.

[0111] Cracked durum wheat kernels (eg Figure 7a The largest particles come from the kernel of the cereal, which, unlike conventional milling, resists breaking without pressure, and the finest particles come from the protein matrix, varying for example from 50 μm to 150 μm.

[0112] During the preparation of this crumb flour by scalding at about 90-100°C, these cells absorb a large amount of water and swell more than starch cells. The oxygen in the water breaks up the proteins in the cells and produces the aroma and quality of these grains. During baking, the living cells that have been damaged by scalding are destroyed and the development of mold or other changes is slowed, thereby extending the shelf life of the bread. In addition, compared with traditional bread, the white part of the bread containing the crumb flour according to the present invention has a higher moisture content, which advantageously extends the shelf life of the bread.

[0113] List of numbers in the accompanying drawings

[0114] Machines for grinding cereals, such as grains1

[0115] Cabin 16

[0116] Neutral gas (nitrogen) source 17

[0117] Entrance 19

[0118] Exit 20

[0119] Feeding device 21

[0120] Funnel 22

[0121] Metering dispenser 23

[0122] Distribution roller 24

[0123] Spline 25

[0124] Conveying device 26

[0125] Conveyor belt / vibrating belt 27

[0126] Crushing device 2

[0127] First comb roller 3

[0128] Rotation axis A1

[0129] First tooth 5

[0130] Conical shape

[0131] Rounded top 9

[0132] Circular sector of teeth

[0133] Circular gap sector

[0134] Leading Edge 11

[0135] Trailing Edge 13

[0136] Transverse tooth clearance 7

[0137] Flared shape

[0138] Rounded groove 15

[0139] Second comb roller 4

[0140] Rotation axis A2

[0141] Second tooth 6

[0142] Conical shape rounded groove 10

[0143] Circular sector of teeth

[0144] Tangent gap circular sector

[0145] Leading Edge 12

[0146] Trailing Edge 14

[0147] Tooth clearance 8

[0148] Conical shape rounded groove 16

[0149] Drying device 28

[0150] Grain 30

[0151] Core (starch, gluten)

[0152] cell

[0153] Germ

[0154] Seed coat

[0155] Protein Matrix

[0156] comb

[0157] Debris 31

[0158] parameter

[0159] Transverse tooth pitch (pitch) P

[0160] Roll gap width (between roll teeth) W

[0161] The first roller diameter D1

[0162] The second roller diameter D2

[0163] Tooth taper angle α

[0164] The tangent length T1 of the first roller tooth

[0165] The tangent length of the first roller tooth gap E1

[0166] The tangent length T2 of the second roller's teeth

[0167] The tangent length of the tooth gap of the second roller is E2

[0168] Top fillet radius R

[0169] The leading edge angle of the first roller (relative to the radial direction) β1

[0170] Trailing edge angle of the first roller (relative to the radial direction)

[0171] The second roller front edge angle (relative to the radial direction) β2 The second roller rear edge angle (relative to the radial direction) The circular sector angle σ1 of the teeth of the first roller

[0172] The circular sector angle ω1 of the tooth gap of the first roller

[0173] The circular sector angle σ2 of the teeth of the second roller

[0174] Circular sector angle of the tooth gap of the second roller ω2 Tangential speed of the first roller (at maximum diameter) V1 Tangential speed of the second roller (at maximum diameter) V2 Speed ​​ratio V1 / V2

Claims

1. A machine for grinding cereal grains (1), the machine comprising a plurality of crushing devices (2), each crushing device comprising a first comb roller (3) rotating about a first rotation axis (A1) and a second comb roller (4) rotating about a second rotation axis (A2), the first comb roller comprising a plurality of first tooth (5) radii about the rotation axis (A1), the second comb roller comprising a plurality of second tooth (6) radii about the second rotation axis (A2), the first tooth radii and the second tooth radii having complementary overlapping shapes, the gap width (W) between the teeth of the rollers being greater than 0, the first comb roller (3) and the second comb roller (4) being driven in rotation by one or more motors, the motors being configured to drive the first teeth at a tangential speed (V1) greater than the tangential speed (V2) of the second teeth, the one or more upstream crushing devices having a larger roller gap width (W) than the downstream crushing device.

2. A machine according to the preceding claim, It is characterized in that The first tooth (5) has a conical shape, and the angle (α) of the conical shape is in the range of 15 degrees to 45 degrees when viewed in cross section on a radial plane.

3. A machine according to any one of the preceding claims, It is characterized in that The tops of the teeth have a rounded shape.

4. A machine according to any one of the preceding claims, It is characterized in that A tangent length (T1) of the first tooth between the leading edge (11) and the trailing edge (13) is greater than a tangent length (T2) of the second tooth (6) between the leading edge (12) and the trailing edge (14), for example, a tangent length ratio (T2 / T1) of the second tooth (6) relative to the first tooth (5) is in the range of 0.2 to 0.

8.

5. A machine according to any one of the preceding claims, It is characterized in that The first comb roller (3) is configured to rotate at a tangential speed (V1) between 1 and 5 times the tangential speed (V2) of the second comb roller.

6. A machine according to any one of the preceding claims, It is characterized in that The first tooth of the first comb roller comprises a leading edge (11) inclined relative to a radial direction passing through the leading edge base along the rotation direction of the first comb roller (3), for example, the inclination angle (β1) of the leading edge relative to the radial direction of the first roller is between 5 degrees and 45 degrees, preferably between 10 degrees and 35 degrees.

7. A machine according to any one of the preceding claims, It is characterized in that The second tooth (6) of the second comb roller comprises a trailing edge (13) inclined relative to a radial direction passing through the base of the trailing edge in the direction of rotation of the second comb roller (4), for example, the trailing edge has an inclination angle relative to the radial direction of the second roller of Between 0 degrees and 40 degrees, preferably between 5 degrees and 30 degrees.

8. A machine according to any one of the preceding claims, It is characterized in that The machine comprises a mechanism for adjusting the distance between the first axis of rotation (A1) and the second axis of rotation (A2) in order to adjust the gap width (W) between the first roller and the second roller.

9. Machine according to any of the preceding claims, comprising a plurality of conveying devices (26) configured to convey grain fragments between the crushing devices and from the last crushing device to an outlet (20) of the machine.

10. A machine according to any one of the preceding claims, It is characterized in that The machine comprises a cabin (16) and a neutral gas source (17) such as nitrogen connected to the cabin (16). The cabin is filled with neutral gas. The crushing device (2) is arranged in the cabin (16). Optionally, the cabin is sealed so that negative pressure can be generated in the cabin.

11. A machine according to any one of the preceding claims, It is characterized in that The machine comprises a feed device (21) located at the machine inlet (19), the feed device comprising a metering distributor (23), the metering distributor comprising a distribution roller (24) with splines (25), the distribution roller (24) being driven in rotation by the machine's motor.

12. A machine according to any one of the preceding claims, It is characterized in that The machine comprises at least one drying device (28) placed between the two crushing devices, for example a device for drying the grain crumbs by radiant heat and / or ventilation, optionally at least one drying device is arranged before the machine outlet (20) for toasting the crumbs.

13. A method for grinding plant grains (such as grains) using a machine, the machine comprising a crushing device (2), the crushing device comprising a first comb roller (3) rotating about a first rotation axis (A1) and a second comb roller (4) rotating about a second rotation axis (A2), the first comb roller comprising a plurality of first tooth (5) radii about the rotation axis (A1), the second comb roller comprising a plurality of second tooth (6) radii about the second rotation axis (A2), the first tooth radius and the second tooth radius having a complementary overlapping shape, the first comb roller (3) and the second comb roller (4) being driven to rotate by one or more motors, the motor being configured to drive the first tooth at a tangential speed (V1) greater than the tangential speed (V2) of the second tooth, the method comprising the step of crushing the grains between the first tooth (5) and the second tooth (6), the first tooth and the second tooth being separated by a gap having a width W greater than 0.09 mm and less than the average grain size of the grains, the gap being configured to crush the grains or grain fragments into fragments by shearing and folding effects, with a large part of the crushing surface not rubbing against the teeth.

14. The method according to the preceding claim, It is characterized in that The machine comprises one or more of the additional features of a machine according to any one of claims 1 to 12, for crushing cereals.

15. Cereal crumb flour obtained by the method according to any one of the two preceding claims, comprising the following characteristics: - average size of the debris: between 90 μm and 5 mm, preferably between 0.1 mm and 2 mm, for example 0.2 mm to 1 mm; - Number of intact cells on the crushed surface of the debris, on average: greater than 30%, preferably greater than 40%, for example greater than 50%.

16. Bread comprising the cereal crumb flour according to the preceding claim in a proportion by dry weight of 5% to 50%, preferably between 20% and 40%, for example between 25% and 35%, of the total dry weight of flour forming the bread.

17. A method of making bread according to the preceding claim, wherein the method include: - Wet and blanch the crumb powder, -Prepare bread dough by adding starch flour to crumb flour in proportion, -Bake the bread dough in the oven.

18. A machine for grinding cereal grains (1), the machine comprising one or more crushing devices (2), the crushing devices comprising a first comb roller (3) rotating about a first rotation axis (A1) and a second comb roller (4) rotating about a second rotation axis (A2), the first comb roller comprising a plurality of first tooth (5) radii about the rotation axis (A1), the second comb roller comprising a plurality of second tooth (6) radii about the second rotation axis (A2), the first tooth radius and the second tooth radius having a complementary overlapping shape, the gap width (W) between the teeth of the rollers being greater than 0, the first comb roller (3) and the second comb roller (4) being driven in rotation by one or more motors, the motors being configured to drive the first teeth at a tangential speed (V1) greater than the tangential speed (V2) of the second teeth, the first teeth of the first comb roller comprising a leading edge (11) inclined relative to a radial direction passing through the leading edge base in the rotation direction of the first comb roller (3).

19. Machine according to the preceding claim, It is characterized in that The inclination angle (β1) of the leading edge relative to the radial direction of the first roller is between 5 degrees and 45 degrees, preferably between 10 degrees and 35 degrees.

20. A machine according to claim 18 or 19, It is characterized in that The first tooth (5) has a conical shape, and the angle (α) of the conical shape is in the range of 15 degrees to 45 degrees when viewed in cross section on a radial plane.

21. A machine according to any one of the preceding claims 18 to 20, It is characterized in that The tops of the teeth have a rounded shape.

22. A machine according to any one of the preceding claims 18 to 21, It is characterized in that A tangent length (T1) of the first tooth between the leading edge (11) and the trailing edge (13) is greater than a tangent length (T2) of the second tooth (6) between the leading edge (12) and the trailing edge (14), for example, a tangent length ratio (T2 / T1) of the second tooth (6) relative to the first tooth (5) is in the range of 0.2 to 0.

8.

23. A machine according to any one of the preceding claims 18 to 22, It is characterized in that The first comb roller (3) is configured to rotate at a tangential speed (V1) between 1 and 5 times the tangential speed (V2) of the second comb roller.

24. A machine according to any one of the preceding claims 18 to 23, It is characterized in that The second tooth (6) of the second comb roller comprises a trailing edge (13) inclined relative to a radial direction passing through the base of the trailing edge in the direction of rotation of the second comb roller (4), for example, the trailing edge has an inclination angle relative to the radial direction of the second roller of Between 0 degrees and 40 degrees, preferably between 5 degrees and 30 degrees.

25. A machine according to any one of the preceding claims 18 to 24, It is characterized in that The machine comprises a mechanism for adjusting the distance between the first axis of rotation (A1) and the second axis of rotation (A2) in order to adjust the gap width (W) between the first roller and the second roller.

26. Machine according to any one of the preceding claims 18 to 25, It is characterized in that The machine comprises a plurality of crushing devices, wherein the upstream crushing device has a larger roller gap width (W) than the downstream crushing device.

27. A machine according to any one of the preceding claims 18 to 26, It is characterized in that The machine comprises a cabin (16) and a neutral gas source (17) such as nitrogen connected to the cabin (16). The cabin is filled with neutral gas. The crushing device (2) is arranged in the cabin (16). Optionally, the cabin is sealed so that negative pressure can be generated in the cabin.

28. A machine according to any one of the preceding claims 18 to 27, It is characterized in that The machine comprises a feed device (21) located at the machine inlet (19), the feed device comprising a metering distributor (23), the metering distributor comprising a distribution roller (24) with splines (25), the distribution roller (24) being driven in rotation by the machine's motor.

29. A machine according to any one of the preceding claims 18 to 28, It is characterized in that The machine comprises at least one drying device (28) placed between the two crushing devices, for example a device for drying the grain crumbs by radiant heat and / or ventilation, optionally at least one drying device is arranged before the machine outlet (20) for toasting the crumbs.

30. A machine for grinding cereal grains (1), the machine comprising one or more crushing devices (2), the crushing devices comprising a first comb roller (3) rotating about a first rotation axis (A1) and a second comb roller (4) rotating about a second rotation axis (A2), the first comb roller comprising a plurality of first tooth (5) radii about the rotation axis (A1), the second comb roller comprising a plurality of second tooth (6) radii about the second rotation axis (A2), the first tooth radii and the second tooth radii having complementary overlapping shapes, the gap width (W) between the teeth of the rollers being greater than 0, the first comb roller (3) and the second comb roller (4) being driven to rotate by one or more motors, the motors being configured to drive the first teeth at a tangential speed (V1) greater than the tangential speed (V2) of the second teeth, the machine comprising a cabin (16) and a neutral gas source (17) such as nitrogen connected to the cabin (16), the cabin being filled with the neutral gas, the crushing device (2) being arranged in the cabin (16).

31. Machine according to the preceding claim, It is characterized in that The cabin is sealed so that a negative pressure can be created within the cabin.

32. A machine according to claim 30 or 31, It is characterized in that The first tooth (5) has a conical shape, and the angle (α) of the conical shape is in the range of 15 degrees to 45 degrees when viewed in cross section on a radial plane.

33. A machine according to any one of the preceding claims 31 to 32, It is characterized in that The tops of the teeth have a rounded shape.

34. A machine according to any one of the preceding claims 31 to 33, It is characterized in that A tangent length (T1) of the first tooth between the leading edge (11) and the trailing edge (13) is greater than a tangent length (T2) of the second tooth (6) between the leading edge (12) and the trailing edge (14), for example, a tangent length ratio (T2 / T1) of the second tooth (6) relative to the first tooth (5) is in the range of 0.2 to 0.

8.

35. A machine according to any one of the preceding claims 31 to 34, It is characterized in that The first comb roller (3) is configured to rotate at a tangential speed (V1) between 1 and 5 times the tangential speed (V2) of the second comb roller.

36. A machine according to any one of the preceding claims 31 to 35, It is characterized in that The first tooth of the first comb roller comprises a leading edge (11) inclined relative to a radial direction passing through the leading edge base along the rotation direction of the first comb roller (3), for example, the inclination angle (β1) of the leading edge relative to the radial direction of the first roller is between 5 degrees and 45 degrees, preferably between 10 degrees and 35 degrees.

37. A machine according to any one of the preceding claims 31 to 36, It is characterized in that The second tooth (6) of the second comb roller comprises a trailing edge (13) inclined relative to a radial direction passing through the base of the trailing edge in the direction of rotation of the second comb roller (4), for example, the trailing edge has an inclination angle relative to the radial direction of the second roller of Between 0 degrees and 40 degrees, preferably between 5 degrees and 30 degrees.

38. A machine according to any one of the preceding claims 31 to 37, It is characterized in that The machine comprises a mechanism for adjusting the distance between the first axis of rotation (A1) and the second axis of rotation (A2) in order to adjust the gap width (W) between the first roller and the second roller.

39. A machine according to any one of the preceding claims 31 to 38, It is characterized in that The machine comprises a plurality of crushing devices, wherein the upstream crushing device has a larger roller gap width (W) than the downstream crushing device.

40. Machine according to any one of the preceding claims 31 to 39, comprising a plurality of crushing devices (2) and a plurality of conveying devices (26), the conveying devices being configured to convey grain fragments between the crushing devices and from the last crushing device to the outlet (20) of the machine.

41. A machine according to any one of the preceding claims 31 to 40, It is characterized in that The machine comprises a feed device (21) located at the machine inlet (19), the feed device comprising a metering distributor (23), the metering distributor comprising a distribution roller (24) with splines (25), the distribution roller (24) being driven in rotation by the machine's motor.

42. A machine according to any one of the preceding claims 31 to 41, It is characterized in that The machine comprises at least one drying device (28) placed between the two crushing devices, for example a device for drying the grain crumbs by radiant heat and / or ventilation, optionally at least one drying device is arranged before the machine outlet (20) for toasting the crumbs.

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