Grinding device and method

Abstract

TITLE: Grinding device and method The present invention relates to a grinding device characterized in that it comprises a set of pairs of cylinders mounted in series, said pairs of cylinders being divided into three distinct groups, a first group (B1 to B5) used for grinding, a second group (CL1 to CL4) used for breaking and a third group (C1 to C6) used for converting, the grinding device comprising a control module, configured to adjust the rotation speed of each cylinder, the cylinders used for grinding having a speed ratio between the two cylinders of a pair of cylinders of between 2.6 and 3.2, the cylinders used for breaking having a speed ratio between the two cylinders of a pair of cylinders of between 1.26 and 3.1, and the cylinders used for converting having a speed ratio between the two cylinders of a pair of cylinders of between 1.34 and 1.95.Abstract figure: Figure 1.

Description

Title of the invention: Grinding device and method Field of invention

[0001] The present invention relates to a grinding device and method. Prior art

[0002] Historically, grinding in grain mills was carried out on stone millstones.

[0003] Stone milling is a rather brutal and coarse milling (greyer flours with a large part of the grain hulls) to produce wholemeal breads (very thick crusts with a large crumb volume and long shelf life).

[0004] Then, roller milling was developed. Roller milling was a real technical revolution to obtain whiter flours and to end up with new baguette-type breads (less crumb and more crust, short shelf life).

[0005] The idea is to make a progressive grinding without crushing and respecting the different grain sizes: - grinding to remove the cellulosic parts of the grain (the coarse bran), - splitting to isolate the different sizes of semolina, from the largest to the finest, - converting to isolate low flours, white remoulages, brown remoulages and fine bran.

[0006] At each of these passes the flour part is removed and collected in a collection system (flour screw) to make a finished product.

[0007] At the beginning of the 20th century this new mill could include up to thirty milling passes.

[0008] However, it was quickly realized that these processes were too long and ultimately did not produce better quality flours with an excessive energy requirement and were therefore unproductive.

[0009] So the processes were shortened, sometimes to the extreme. Thus, modern milling has become almost as brutal as grinding on stone wheels. Today, mills generally have between eight and twelve grinding passes. This trend is increasing for economic reasons in order to limit investments.

[0010] As a result, flours often need to be corrected after milling and the qualities of the wheat at the inlet need to be standardized.

[0011] Most flours currently produced have high glycemic indices (GI). The glycemic index (GI) is measured as the ratio of the amount under the blood glucose curve during the 2 hours following ingestion of the food studied on that of a reference food (glucose or white bread). Foods with a glycemic index lower than 55 are classified as low glycemic index, those with an index between 56 and 69 are said to have a medium GI and those with an index greater than or equal to 70 are high GI. However, it is now known that a diet rich in high GI foods promotes the development of insulin resistance, type 2 diabetes and also obesity.

[0012] Work has been carried out to optimize bread manufacturing processes in order to reduce the glycemic index, but very little to date has focused on optimizing the raw material: flour.

[0013] All studies agree that it is very important to avoid rough grinding of the grain and to avoid heating it as much as possible so as not to damage the micronutrients and the structure of the starch granule. Damage to the structure of the latter leads to an increase in the glycemic index of the flour. It turns out that current grinding procedures, whether with stone mills or rollers, are not satisfactory and are still too drastic. Maximum grinding speed and temperature instructions not to be exceeded as well as alternatives such as induction mills are proposed in patents (for example in document CN107081189), but the development of a slow and gentle process requires efficient processes / devices and the expertise of the miller.

[0014] Beyond this aspect, recent results of scientific studies tend to show that - in the case of wholemeal flours - the granulosity of the bran particles and their treatment is of prime importance for the nutritional, functional and stability qualities of the flour. A fairly high granulosity (400 - 500 pm in diameter) seems to be the ideal compromise between low disruption of the gluten network and lowering of the glycemic index. On the other hand, it seems that this parameter is little or not controlled in current flour mills. Statement of the invention

[0015] There is therefore a need for a milling process and device which makes it possible to obtain flours of better quality and with a lower GI, while being economically viable.

[0016] These objectives, as well as others which will appear more clearly hereinafter, are achieved using a grinding device characterized in that it comprises a set of pairs of cylinders mounted in series, said pairs of cylinders being divided into three distinct groups, a first group used for grinding, a second group used for breaking and a third group used for converting, the grinding device comprising a control module, configured to adjust the rotational speed of each roll, the rolls used for grinding having a speed ratio between the two rolls of a pair of rolls of between 2.6 and 3.2, the rolls used for breaking down having a speed ratio between the two rolls of a pair of rolls of between 1.26 and 3.1, and the rolls used for converting having a speed ratio between the two rolls of a pair of rolls of between 1.34 and 1.95.

[0017] The set of pairs of cylinders comprises, for example, fifteen pairs of cylinders.

[0018] The first group used for grinding may comprise five pairs of cylinders, the second group used for breakdown may include four pairs of cylinders, and the third group used for conversion may include six pairs of cylinders.

[0019] According to one embodiment of the invention, the rotation values ​​of the fast cylinder (in revolutions / min), of the slow cylinder (in revolutions / minutes) and of the corresponding speed ratio are:

[0020] B1 = 300 / 115 -2.6

[0021] B2 = 300 / 105 - 2.9

[0022] B3 = 330 / 115 -2.8

[0023] B4 = 260 / 80 - 3.2

[0024] B5 = 260 / 80 - 3.25

[0025] Where B1 to B5 respectively denote the five pairs of cylinders of the first group of pairs of cylinders.

[0026] According to one embodiment of the invention, the rotation values ​​of the fast cylinder (in revolutions / min), of the slow cylinder (in revolutions / minutes) and of the corresponding speed ratio are:

[0027] CL1 = 250 / 80 - 3.12

[0028] CL2 = 215 / 170- 1.26

[0029] CL3 = 215 / 165- 1.3

[0030] CL4 = 145 / 110- 1.32

[0031] Where CL1 to CL4 respectively designate the four pairs of cylinders of the second group of pairs of cylinders.

[0032] According to one embodiment of the invention, the rotation values ​​of the fast cylinder (in revolutions / min), of the slow cylinder (in revolutions / minutes) and of the corresponding speed ratio are:

[0033] 01=215 / 110-1.95

[0034] 02 = 270 / 215- 1.25

[0035] 03 = 215 / 160- 1.34

[0036] 04 = 215 / 160- 1.34

[0037] 05 = 215 / 160- 1.34

[0038] C6 = 215 / 160- 1.34

[0039] Where C1 to C6 respectively denote the six pairs of cylinders of the third group of pairs of cylinders.

[0040] The invention also relates to a grinding method intended to be implemented by the grinding device described above, characterized in that it comprises:

[0041] - a grain feeding step, in which the raw grains are fed to the grinding device from a feed module,

[0042] - a grinding step, in which the grains are introduced into the pairs of cylinders of the first group of pairs of cylinders where they undergo an initial grinding,

[0043] - a breakdown step, in which the resulting grind of the initial grinding is transferred into the cylinder pairs of the second group of cylinder pairs,

[0044] - a converting step, in which the slammed grind is conveyed to the pairs of cylinders of the third group of pairs of cylinders, and

[0045] - a flour removal step, in which the flour obtained is removed from the grinding device and ready for packaging or use in various food applications.

[0046] The grinding, breaking and converting steps can be repeated several times, preferably sixteen times.

[0047] List of figures

[0048] The invention will be better understood on reading the following description of preferred embodiments, given as a simple figurative and non-limiting example, and accompanied by the figures among which: - [Fig.l] is a partial functional view of a grinding device according to one embodiment of the invention; and - [Fig.2] is a diagram of the steps of a milling process according to a method of realization of the invention. Detailed description of embodiments of the invention 1. Device

[0049] [Fig.l] represents a grain grinding device.

[0050] The grinding device comprises a set of pairs of cylinders connected in series. The set of pairs of cylinders comprises, for example, fifteen pairs of cylinders.

[0051] The purpose of the milling device is to efficiently perform the initial grinding, intermediate breaking, and final conversion of the grains, thereby achieving uniform particle size and the desired conversion of raw materials (grains) into finished products (flours).

[0052] The pairs of cylinders are mounted in series with respect to each other, in a horizontal plane.

[0053] Each cylinder is rotatably mounted around its axis.

[0054] The pairs of cylinders are divided into three distinct groups: a first group used for grinding, a second group used for breaking down and a third group used for converting. For example, the first group used for grinding comprises five pairs of cylinders B1 to B5, the second group used for breaking down comprises four pairs of cylinders CL1 to CL4, and the third group used for converting comprises six pairs of cylinders C1 to C6.

[0055] The cylinders of each pair are spaced apart from each other, the distance between the two cylinders of the pair being adjustable. The distance between the cylinders of each pair is adjusted using precise adjustment mechanisms, allowing precise control of the particle size and the degree of grain conversion at each stage of the process.

[0056] The milling device comprises a feed module 1, configured to convey the grains to the first pair of cylinders B1. The device comprises a discharge module 2, configured to discharge the flour at the outlet of the last pair of cylinders C6.

[0057] The grains to be treated are thus introduced into the first group of cylinders B1 to B5, where they undergo initial grinding. The resulting grind is transferred to the second group of cylinders CL1 to CL4 for intermediate breaking, then finally to the third group of cylinders C1 to C6 for final conversion.

[0058] The cylinders are, for example, made of metal and have grinding surfaces adapted to the different stages of the process. Their surfaces can be smooth or grooved.

[0059] The grinding device includes a safety module to prevent any accidents during its operation. Cleaning and maintenance modules may also be provided to facilitate its maintenance in good working order.

[0060] The grinding device comprises a control module, configured to adjust the rotational speed of each cylinder B1 to B5, CL1 to CL4 and C1 to C6. The cylinders of each pair of cylinders are adjusted to rotate at different speeds, thus creating a specific grinding action. The speed of the cylinders and the speed ratio between the fast cylinder and the slow cylinder of each pair, substantially determines the quality of the grinding.

[0061] The grinding cylinders B1 to B5 have a speed ratio between the two cylinders of each pair of between 2.6 and 3.2.

[0062] Thus, the fast cylinder of pair B1 rotates at 300 rpm and the slow one at 115 rpm, i.e. a ratio of 2.6. For grinder B5 this ratio is 3.25.

[0063] Grinding at a relatively slow speed promotes a gentle progressive decomposition of the ground material to obtain clean, uncovered bran and separation rapid crushing of the floury part of the ground material.

[0064] An example of the rotation values ​​of the fast cylinder (in revolutions / min), the slow cylinder (in revolutions / minutes) and the corresponding speed ratio is given below: B1 = 300 / 115-2.6 B2 = 300 / 105 - 2.9 B3 = 330 / 115 -2.8 B4 = 260 / 80 - 3.2 B5 = 260 / 80 - 3.25

[0065] The slamming cylinders have a speed ratio between the two cylinders of 3.1 for the pair CL1 and approximately 1.3 for the other three pairs CL2, CL3 and CL4.

[0066] The speed of the fast cylinder is between 145 and 250 revolutions / minute.

[0067] The CL1 pair works with relatively large semolina that the rapid passage combined with a fairly wide spacing between the cylinders allows for care to be taken to avoid damaging the grain structure.

[0068] The CL2 pair and the following CL3 and CL4 have a speed ratio between 1.26 and 1.32 and are tighter while taking care not to damage the starch of the flour.

[0069] An example of the rotation values ​​of the fast cylinder (in revolutions / min), the slow cylinder (in revolutions / minutes) and the corresponding speed ratio is given below: CL1 = 250 / 80-3.12 CL2 = 215 / 170- 1.26 CL3 = 215 / 165- 1.3 CL4 = 145 / 110- 1.32

[0070] The conversion cylinders C1 to C6 have a speed ratio between the two cylinders of between 1.34 and 1.95.

[0071] The converting cylinders, in particular the cylinders of pair C1, have the task of not damaging the starch.

[0072] The cylinders are adjusted in such a way as not to heat the flour. Thus, when touched by hand, the temperature of the cylinder is just lukewarm.

[0073] The speed of the fast cylinder is between 215 and 270 rpm.

[0074] An example of the rotation values ​​of the fast cylinder (in revolutions / min), of the slow cylinder (in revolutions / minute) and the corresponding speed ratio: Cl = 215 / 110-1.95 C2 = 270 / 215 - 1.25 C3 = 215 / 160- 1.34 C4 = 215 / 160- 1.34 C5 = 215 / 160- 1.34 C6 = 215 / 160- 1.34 1. Process

[0075] The steps of the milling method according to one embodiment of the invention are described below.

[0076] The method comprises a grain feeding step SI, in which the raw grains are fed to the grinding device from the feeding module 1. A precise feeding mechanism ensures a uniform flow of grains to the grinding device.

[0077] The method comprises an initial grinding step S2, in which the grains are introduced into the first grinding chamber where they undergo initial grinding. This step is carried out by the pairs of cylinders B1 to B5. This step S2 reduces the particle size while preserving the integrity of the essential components of the grains.

[0078] The method comprises an intermediate breaking step S3, in which the resulting grind from the initial grinding is transferred to the second breaking chamber, where a carefully controlled breaking action is applied. This step is carried out by the pairs of cylinders CL1 to CL4. This allows for further breaking of the particles and improvement of the texture of the flour.

[0079] The method comprises a final conversion step S4, in which the slammed grind is conveyed to the third converting chamber, where it is subjected to final conversion. This step is carried out by the pairs of cylinders C1 to C6. This step optimizes the particle size of the flour and makes it possible to achieve the desired grinding fineness.

[0080] Steps S2 to S4 are carried out with the settings of the spacing of the cylinders of each pair, the speed of each cylinder and the speed ratio between the cylinders of each pair described above with reference to the milling device. Steps S2 to S4 can be repeated several times. This iteration makes it possible to further improve the quality of the final flour. Steps S2 to S4 are for example repeated sixteen times.

[0081] The method comprises a step S5 of separating the components, in which the resulting flour is separated from unwanted particles such as husks or impurities. A sieving or separation system is used to ensure the purity of the flour.

[0082] The method comprises a flour discharging step S6, in which the obtained high-quality flour is discharged from the milling device and ready to be packaged or used in various food applications.

[0083] This milling process offers several advantages, including efficient production, consistent flour quality, and preservation of the nutritional components of the raw grains.

[0084] This milling process is applicable to various food industries, including bakery, pastry, pasta production and many others, where a flour of high quality is essential for the manufacture of superior finished products.

[0085] The table below shows a comparison of some characteristics of the flour obtained by the process of the invention and a current classic flour: Batch Proteins Height Hagberg Ashes Flour according to the invention 7 11.7 13.8 353 1.54 Classic flour 623545 10.9 13.9 345 1.4

[0086] The grain size also presents differences.

[0087] Finished product according to the invention: -flour 65.08 gr (160my) -round flours 12.58 gr (180 my) -fine sounds and remoldings 13.60gr - 4.02gr recoupettes -large sounds 3.62gr

[0088] Classic finished product: -flour 52.53 gr (160my) - round flours 9.38 gr (180 my) -fine bran and regrindings 26.85gr - 9.20gr recoupettes -big sounds O.OOgr

[0089] As can be seen, the assembly of the granulometries is completely different between the two flours.

[0090] The gentle grinding of the flour obtained according to the invention is more balanced, with a total flour of 77.66%, compared to a total flour of 61.91% for conventional flour.

[0091] The quantity of flour is therefore much better extracted in gentle milling than with current industrial processes.

[0092] In addition, the extracted flour part is not only greater in quantity but also has a lower glycemic index, of the order of 10%.

Claims

Claims

1. Grinding device characterized in that it comprises a set of pairs of cylinders mounted in series, said pairs of cylinders being divided into three distinct groups, a first group (B1 to B5) used for grinding, a second group (CL1 to CL4) used for breaking and a third group (Cl to C6) used for converting, the grinding device comprising a control module, configured to adjust the rotation speed of each cylinder, the cylinders used for grinding having a speed ratio between the two cylinders of a pair of cylinders of between 2.6 and 3.2, the cylinders used for breaking having a speed ratio between the two cylinders of a pair of cylinders of between 1.26 and 3.1, and the cylinders used for converting having a speed ratio between the two cylinders of a pair of cylinders of between 1.34 and 1.

95.

2. A grinding device according to claim 1, wherein the set of cylinder pairs comprises fifteen cylinder pairs.

3. A grinding device according to claim 2, wherein the first group used for grinding comprises five pairs of cylinders (B 1 to B5), the second group used for breaking comprises four pairs of cylinders (CL1 to CL4), and the third group used for converting comprises six pairs of cylinders (C1 to C6).

4. A grinding device according to claim 3, wherein the rotation values ​​of the fast cylinder (in rpm), the slow cylinder (in rpm) and the corresponding speed ratio are: B1 = 300 / 115 -2.6 B2 = 300 / 105 - 2.9 B3 = 330 / 115 -2.8 B4 = 260 / 80 - 3.2 B5 = 260 / 80 - 3.25 Where B1 to B5 respectively denote the five pairs of cylinders of the first group of pairs of cylinders.

5. Grinding device according to claim 3 or 4, wherein the rotation values ​​of the fast cylinder (in revolutions / min), the slow cylinder (in revolutions / minutes) and the corresponding speed ratio are: CL1 = 250 / 80- 3.12 CL2 = 215 / 170- 1.26 CL3 = 215 / 165- 1.3 CL4 = 145 / 110- 1.32 Where CL1 to CL4 respectively denote the four pairs of cylinders of the second group of pairs of cylinders.

6. A grinding device according to any one of claims 3 to 5, wherein the rotation values ​​of the fast cylinder (in rpm), the slow cylinder (in rpm) and the corresponding speed ratio are: Cl =215 / 110- 1.95 C2 = 270 / 215 - 1.25 C3 = 215 / 160- 1.34 C4 = 215 / 160- 1.34 C5 = 215 / 160- 1.34 C6 = 215 / 160- 1.34 Where Cl to C6 respectively denote the six pairs of cylinders of the third group of pairs of cylinders.

7. A milling method to be carried out by the milling device according to any one of claims 1 to 6, characterized in that it comprises: - a grain feeding step, in which the raw grains are fed to the milling device from a feed module (1), - a grinding step, in which the grains are introduced into the pairs of cylinders of the first group of pairs of cylinders (B 1 to B5) where they undergo initial grinding, - a breaking step, in which the grind resulting from the initial grinding is transferred to the pairs of cylinders of the second group of pairs of cylinders (CL1 to CL4), - a converting step, in which the broken grind is fed to the pairs of cylinders of the third group of pairs of cylinders (C1 to C6), and - a flour discharge step,in which the resulting flour is discharged from the milling device and ready for packaging or use in various food applications.,

8. A milling method according to claim 7, wherein the grinding, breaking and converting steps are repeated several times, preferably sixteen times.

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