BE1023082B1 - Product of low iron cultivated grain - Google Patents

Abstract

A process for obtaining, starting from whole grains, a fraction of grains (F) having a reduced iron content of at least 25% by weight relative to an initial iron content of said whole grains, said process comprising the following steps: Step 1: a step of processing said whole grains, Step 2: a step of separating said grains treated in step 1 so as to obtain a first fraction of grains (F1) and a second fraction of grains ( F2), and Step 3: a step of separating said first fraction of grains (F1) obtained in step 2, on the basis of the size and / or the shape of said first fragments, so as to isolate said fraction of grains (F) having said reduced iron content.

Description

"Product of grain grown low in iron"

Technical area

The present invention relates to a process for obtaining a grain fraction derived from grains of cereals, oilseeds and / or legumes having a reduced iron content while retaining good nutritional properties and a good energy value. The present invention also relates to fractions and processed products obtained from said fraction obtained according to the process according to the invention.

Prior state of the art

The iron (Fe) content is of great importance in certain types of animal feed, iron being able to come from various sources. On the one hand, iron can be naturally present in the raw material used to manufacture animal feed. On the other hand, iron can also be added to the food, in order to achieve a desired iron content in the case where the initial content is insufficient. Finally, iron can also come from the friction of the raw material against metal elements in the processing facilities of the production line.

It is well known that iron affects many metabolic functions, including the amount of hemoglobin in red blood cells and the amount of red blood cells in the blood. In addition, iron can influence the color of the animal flesh, and thus, after slaughter of the animal, on the color of the meat.

In some animal breeding chains, such as beef veal breeding, it is desirable to obtain meat with a color ranging from white to pink, an animal feed that is too rich in iron and detrimental to the production of meat. of such a color of meat. Thus, some raw materials can not be part of the diet of some animals because of their too high iron content which has a direct impact on the appearance of the meat, mainly on the color of the latter. Animal feed, especially calf feed, consists of a combination of a liquid-type feed (based on dairy products, eg breast milk) and a solid-type feed (eg a feed). essentially dry grain-based).

One solution for limiting the iron content could be to increase the proportion of liquid-type feeds in the calf feed compared to the solid-type feed, since the liquid-type feed typically has an iron content. particularly weak.

Unfortunately, this solution has a major disadvantage since a diet solely or essentially liquid would have a negative impact on the welfare of animals including calves.

It would therefore be preferable, on the contrary, to increase the proportion of solid foods, rich in starch, in animal feed compared to the proportion of liquid-type foods. However, in this case, the iron content of solid foods often remains too high, which limits the amount of solid food that can be present in the calves' diet.

Among cereals, maize is widely used as a feedstock for calves. In addition, farmers and producers aim to increase their share in the calves' diet. Indeed, maize has good digestibility, good palatability and excellent nutritional properties, such as a naturally low iron content, typically in the range of 30 mg / kg to 40 mg / kg, and a good balance between the fat content and the starch content. However, as mentioned above and despite the fact that maize has a relatively low iron content, increasing the proportion of this cereal in the food ration inevitably leads to an excessively high iron content. This is therefore opposed to obtaining a pink-white meat yet sought especially by consumers. This problem is all the more marked with other cereals, with oilseeds and with legumes whose iron content may be higher than those found for maize.

There is therefore a real need to develop and propose a diet comprising a fraction of grains grown (cereals, oleaginous and / or legumes) with a reduced iron content while maintaining good nutritional properties, including a good balance between fat content and starch content, good digestibility, good palatability, and a good energy value, this diet can be given to animals in higher proportions. There remains the need to provide a process for the manufacture of this fraction present in the diet. Finally, there remains a need to develop processed products of said fraction having reduced iron content, while also retaining good nutritional properties, good digestibility and palatability, and good energy value. Summary of the invention

Surprisingly, the applicant has found that the process of the present invention makes it possible to obtain a fraction of grains having a reduced iron content relative to the initial iron content of the whole grains, while maintaining good nutritional properties, especially suitable for fat and starch, good digestibility and palatability, and good energy value.

More particularly, to cope with the needs mentioned above, the invention proposes a process for obtaining, from whole grains selected from the group consisting of at least one cereal grain, at least one grain of oilseeds, from at least one leguminous grain and a mixture thereof, a grain fraction (F) having an iron content reduced by at least 25% by weight relative to an initial iron content said whole grains, said process comprising the following steps:

Step 1: a step of treating said whole grains,

Step 2: a step of separating said grains treated in step 1 so as to obtain a first grain fraction (Fi) comprising first grain fragments having a particle size greater than one or more predetermined threshold values of size of particles and a second grain fraction (F2) comprising second grain fragments having a particle size smaller than said predetermined particle size threshold value (s), and

Step 3: a step of separating said first grain fraction (F1) obtained in step 2, on the basis of the size and / or shape of said first fragments, so as to isolate said grain fraction (F) having said reduced iron content.

Advantageously, according to the process according to the invention, the fraction of grains (F) has a reduced iron content of at least 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight. % by weight, preferably at least 55% by weight, preferably at least 60% by weight relative to the initial iron content of the whole grain.

Preferably, according to the process according to the invention, said grain fraction (F) is obtained from whole grains being corn kernels.

Preferably, according to the process according to the invention, said grain fraction (F) obtained from whole grains being maize grains has a maximum reduced iron content of 30.0 mg / kg, preferably a reduced iron content. 25.0 mg / kg, preferably a maximum reduced iron content of 20.0 mg / kg, more preferably a maximum reduced iron content of 15.0 mg / kg, preferably a maximum reduced iron content of 13. , 0 mg / kg, preferably a maximum reduced iron content of 12.5 mg / kg, more preferably a maximum reduced iron content of 12.0 mg / kg.

Advantageously, according to the process according to the invention, said grain fraction (F) has a particle size distribution such that: Dg -1000 pm and Dg <6000 pm and D99 = <7000 pm.

Preferably, according to the process according to the invention, said step 1 of whole grain treatment denotes fragmentation carried out by grinding, by friction treatment and / or by abrasive treatment of the whole grains.

Preferably, according to the process according to the invention, step 1 is preceded or followed by a grain conditioning step.

Advantageously, according to the process according to the invention, said step of conditioning the grains comprises one or more cleaning steps, one or more humidification steps and / or one or more polishing steps.

Preferably, according to the method according to the invention, said separation step 2 is carried out by means of a device provided with a perforated screen whose perforations have a rectangular or oval shape.

Preferably, according to the process according to the invention, said perforations having a rectangular or oval shape have a length which is not less than 3.0 mm, preferably not less than 5.0 mm, preferably not less than 7, 0 mm, preferably not less than 10.0 mm, preferably not less than 12.0 mm, said length not being greater than 30.0 mm, preferably not more than 25.0 mm, preferably not more than 20.0 mm, preferably not more than 18.0 mm, preferably not more than 15.0 mm, preferably not more than 14.0 mm, preferably not more than 13.0 mm, preferably not more than 12.0 mm.

Advantageously, according to the method according to the invention, said perforations having a rectangular or oval shape have a width of not less than 0.5 mm, preferably not less than 0.75 mm, preferably not less than 1.0 mm, preferably not less than 1.2 mm, said width not being greater than 6.0 mm, preferably not more than 5.0 mm, preferably not more than 4 mm , 0 mm, preferably not more than 3.0 mm, preferably not more than 2.5 mm, preferably not more than 2.0 mm, preferably not more than 1.5 mm, preferably not more than 1.2 mm.

Advantageously, according to the process according to the invention, said grain fraction (F2) represents at most 50% by weight, preferably at most 45% by weight, preferably at most 40% by weight, preferably at most 35% by weight. weight relative to the total weight of whole grains.

Preferably, according to the process according to the invention, the fraction (F2) represents at least 15% by weight, preferably at least 20% by weight, preferably at least 25% by weight relative to the total weight of whole grains.

Preferably, according to the process according to the invention, the separation of the first fraction (F1) of step 3 comprises a mechanical separation.

Advantageously, according to the process according to the invention, said mechanical separation is carried out using a sieve or a plurality of sieves having meshs of different sizes.

Preferably, according to the process according to the invention, an intermediate grain fraction [hereinafter called grain fraction (F ')] is collected between a sieve in the lower position and a sieve in the upper position, if said sieve in the upper position. is present, or on the sieve in the lower position if a single sieve is used.

Preferably, according to the process according to the invention, said fraction of grains (F) is obtained by subjecting the fraction (F ') to a subsequent separation step by subtracting a fraction of grains (F4).

Advantageously, according to the process according to the invention, said subsequent separation step is carried out using suction means.

Advantageously, according to the process according to the invention, a fraction of grains (F3) is collected after passing through all the sieves, specifically after passing through a sieve in the lower position.

Preferably, according to the process according to the invention, the grain fraction (F) represents at most 80% by weight, preferably at most 75% by weight, preferably at most 70% by weight relative to the total weight of whole grains. .

Preferably, according to the process according to the invention, the fraction of grains (F) represents at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight relative to the total weight of whole grains. .

The present invention also relates to a fraction of grains (F) having a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably at least 35% by weight, preferably at least 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight, preferably at least 60% by weight relative to the initial iron content of the whole grain.

Preferably, according to the invention, said grain fraction (F) has a particle size distribution such that:

Dg -1 1000 pm and Dg + 6000 pm and Dgg, s = 7000 μηη.

The present invention also relates to a fraction of grains (F) obtained according to the process according to the invention.

The present invention also relates to a process for converting a fraction of grains (F) obtained according to the process according to the invention so as to obtain a transformed product.

Preferably, said transformation method according to the invention comprises a step selected from the group consisting of grinding, flattening, toasting, flaking, extrusion, granulation, micronization and an expansion process.

The present invention also relates to a product transformed according to the transformation method according to the invention, said transformed product having a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably at least 35% by weight, preferably at least 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight by weight, preferably at least 60% by weight relative to the initial iron content of the whole grain.

Advantageously, said product converted according to the invention is a flake, an extruded, a granule, a micronized product, a toasted product or an expanded product.

The present invention also relates to a use of the fraction (F) according to the invention in the field of the brewery, the production of fermentation alcohol, the agri-food field, the bakery, and / or the food industry. animal.

The present invention also relates to a use of the processed product according to the invention in the field of brewery, production of fermentation alcohol, agri-food, bakery, and / or animal feed.

The present invention also relates to a compound derived from the grain fraction (F) according to the invention used in the composition of an animal feed.

Detailed description of the invention

Process for obtaining the fraction (F)

As already indicated above, the whole grain used may be a cereal grain, an oilseed grain or a legume grain.

Typical and non-limiting examples of cereal grain are corn kernels, wheat, barley, rice, oats, spelled and derivatives thereof.

Corn derivatives can refer to sweet corn and popcorn.

Oat derivatives may refer to naked avian, peeled oats and shelled oats.

Derived spelled may refer to peeled spelled.

A typical and nonlimiting example of oilseed grain is soybean.

Typical and non-limiting examples of legume grains are lupine, peas, and beans in general.

Preferably, the whole grain used is a cereal grain.

Preferably, the cereal used is corn and the derivatives thereof, or wheat. More preferably, the cereal used is corn.

Corn is often used as a feedstock for calves because of its good digestibility, taste and nutritional properties, for example because of its low fat content and its natural iron content. relatively low.

Advantageously, the corn can be heat-treated, more particularly in order to be transformed into corn flakes, in order to improve its digestibility and taste and to further reduce its iron content, while maintaining a low content of iron. fat.

In the context of the present invention, the expressions "grain" or "grains" are used indifferently.

In the context of the present invention, the expressions "the grain" or "the seed" are used indifferently.

In the context of the present invention, it has been surprisingly determined that the grain fraction (F) resulting from the process of the present invention has a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably at least 35% by weight, preferably at least 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight preferably at least 55% by weight, more preferably at least 60% by weight relative to the initial iron content of the whole grain.

The iron content can be measured spectroscopically, for example by spectroscopy using inductively coupled plasma and can be expressed in mg / kg.

Iron, although undesirable in proportions that are too important in certain types of animal feed, particularly in the feed for veal calves, is nevertheless accepted, even desirable, in small quantities. Indeed, iron is essential in the feed of farm animals to ensure certain metabolic functions as already mentioned above.

For the purposes of the present invention, it is understood that the iron content in the grain fraction (F) is at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least 2.5 mg / kg.

Typically, whole corn kernels have an iron content ranging from 10.0 mg / kg to 50.0 mg / kg, depending on the variety.

In a preferred embodiment of the present invention, when the grain fraction (F) is derived from whole maize grains (hereinafter corn grain fraction (F)) has a reduced iron content compared to the initial iron content of the whole corn kernel. The reduced iron content of corn kernel fraction (F) can be at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least 2.5 mg / kg.

In addition, the reduced iron content of corn grain fraction (F) is at most 30.0 mg / kg, preferably at most 25.0 mg / kg, preferably at most 20.0 mg / kg. kg, more preferably at most 15.0 mg / kg, preferably at most 13.0 mg / kg, preferably at most 12.5 mg / kg, more preferably at most 12.0 mg / kg.

Good results have been obtained for a reduced iron content in the range of 2.5 to 13.0 mg / kg in corn kernel fraction (F).

In the context of the invention, the meat of animals fed with a fraction of grains (F) obtained according to the process of the present invention has a pinkish to light color, preferably corresponding to a maximum of a shade of class 3, preferably at most to a class 2 shade, preferably to a Class 1 shade on the classification chart of the National Inter-professional Meat and Poultry Office (OFIVAL, Paris) (Development and construction of the new color chart of veal, Final Report No. 00 10 32 009 of the Department of Livestock and Quality Technology, Institute of Livestock, 2010, page 42).

The reduced iron content values of the grain fraction (F) are also applicable to the transformed products from said grain fraction (F), as explained in detail below.

In step 1 of the process of the present invention, the whole grain selected from the group consisting of at least one cereal grain, at least one oilseed kernel, at least one legume kernel and at least one a mixture of these is subjected to a treatment. In the context of the present invention, the treatment refers to the action of reducing an entire grain or a derivative thereof in at least two grain fragments, so as to obtain at least first grain fragments and at least second fragments grains. Thus, the grains can be processed in any conventional grain treatment unit to reduce an entire grain into at least two grain fragments.

In the context of the present invention, the term "at least two grain fragments" refers to "two or more grain fragments".

Typical examples of grain processing are described in WO 2005/108533 A2, the entire contents of this application being incorporated herein by reference for all purposes.

In the context of the present invention, the treatment of step 1 denotes the fragmentation of the whole grains optionally packaged.

Specifically, the fragmentation can be carried out by crushing the whole grains, by friction treatment, by abrasive treatment, and / or by cutting the whole grains, preferably by a friction treatment and / or an abrasive treatment, more preferably by a abrasive treatment.

Whole grains can for example be crushed against or under a grinding wheel, or between two rollers.

Friction treatment may for example be carried out in a device in which the grains are brought into contact with one or more moving surfaces. In the case of an abrasive treatment, the grains are brought into contact with one or more moving surfaces having bar, pointed, rounded, or any other shape protuberances.

Examples of machines that can perform an abrasive grain treatment are Bühler's MHXM machine, Satake's "Mize degermer VBF10AM" machine, or a M300, M301 or M350 dehuller from CMF.

It is understood that those skilled in the art will implement the abrasive treatment, using the MHXM Bühler machine according to general practice, including applying all the optimal parameters (number of impact bars, pressure between the rollers,. ..), provided that the grain fractions (Fi) and (F2) are formed, as described in detail below.

According to the invention, said treatment step may also comprise a packaging of said whole grains. Such conditioning may take place prior to step 1 or following step 1.

Conditioning, whether performed before step 1 or after step 1, may comprise for example one or more cleaning steps, one or more moistening steps and / or one or more polishing steps. The cleaning step is performed to remove undesirable elements from the grains. Non-limiting examples of undesirable elements in the process may be pebbles, gravel, sand, glass and other high-density materials, straw and other plant-based elements that are not the desired grains, materials of animal origin, dust, earth, paper, cardboard, metals, grains not having the desired color, ...

Optionally, the cleaning step can be carried out in such a way that undesirable and / or toxic substances, such as, for example, mycotoxins or (residues of) plant protection products (pesticides, herbicides, etc.) are at least partially eliminated.

Cleaning can be done in a conventional cleaning unit.

The cleaning may comprise a washing step with water, a suction step by air flowing through the grains, or a combination of both.

In the case of a washing with water, the water may be in various forms, for example in gaseous form, liquid or constitute an aqueous solution. Optionally, additives could be added to the water. Among the additives that can be added to water, there may be mentioned acids and surfactants.

Non-limiting examples of cleaning devices may be a drum screen, a magnetized drum, a silo in a tank that may have a central axis, a cleanser, and / or a classifier, a non-ferrous metal detector, a metal detector. color or a sieve. All these units can be supplied in particular by Bühler GmbH.

In a particularly advantageous form, the cleaning is carried out with a circulating air flow.

When a conditioning stage is carried out, an MTRA separator and / or an MTSC cleanser from Bühler GmbH could advantageously be used.

Advantageously, the undesirable elements can be sucked into a suction channel out of the cleaning and / or preliminary cleaning unit, where they are collected and separated from the space where the process of the present invention takes place.

According to one embodiment of the method of the present invention, said grain conditioning may optionally include a step of moistening said whole grain to obtain a grain having a certain moisture content. Typically, whole corn kernels have a moisture content of between 6% and 35% by weight based on the weight of the whole corn kernel.

Optionally, if the moisture content is less than 15% by weight, based on the weight of the whole maize grain, said moisture content could be increased by at least 0.5% by weight, preferably from minus 1.0% by weight, preferably at least 1.5% by weight, more preferably at least 2.0% by weight based on the weight of said whole maize grain.

Said humidification step can be carried out according to the methods known from the state of the art.

Advantageously, the whole grain is moistened with water, preferably with water at room temperature. Moisture can be absorbed into the grain for a certain period of time.

In a particularly preferred embodiment of the present invention, the grains may be introduced into a rotating screw under water vapor for about 90 seconds.

According to another embodiment according to the invention, said conditioning of the grain may comprise a polishing step carried out for example by subjecting the whole grain to a series of compressions and relaxations, in order to soften the envelope of the whole grain by friction. .

Advantageously, the polishing step may be carried out in a polishing machine well known in the state of the art, such as, for example, the polishing machine Mist Polisher from Satake.

Advantageously, the polishing machine could comprise a rotating eccentric rotor surrounded by a chamber surrounded by a perforated polygonal screen. With each rotation of the rotor, the space between said rotor and the screen causes alternating compression and relaxation cycles, producing a friction action on the grain.

The grains thus packaged, i.e. for example cleaned and / or moistened and / or polished, can then be processed as described above according to the process of the present invention. In step 2 of the process according to the invention, the grains, once treated according to step 1 of the process according to the invention and optionally packaged, are then separated into two fractions, according to one or more particle size threshold values. . More specifically, the grains are separated into a first grain fraction (Fi) comprising first grain fragments having a particle size greater than one or more predetermined particle size threshold values and a second grain fraction (F2) comprising second grain fragments having a particle size smaller than said predetermined particle size threshold value (s).

In a preferred embodiment of the method of the present invention, step 2 may be performed using a device provided with a perforated screen.

In this embodiment, the grains treated in step 1 and optionally packaged are introduced into said device provided with a perforated screen. This device is designed to retain grain fragments having a particle size larger than one or predetermined threshold particle size values, these retained fragments forming the fraction (F1). In parallel, this device is arranged to pass grain fragments having a particle size smaller than said threshold values, these fragments passing through the device forming the fraction (F2).

Typically, the perforated screen of the device can be a screen made of metal, polymer, wood, or any other type of material.

Typically, the perforated screen comprises at least one perforation that can be of any type of shape, for example a hexagon, a pentagon, an octagon, a square, a rectangle, a circle, a triangle, an oval. Preferably, the perforation is in the form of a rectangle and / or an oval.

Advantageously, the length of the rectangular perforation or the length of the oval perforation is at least 3.0 mm, preferably at least 5.0 mm, preferably at least 7.0 mm, more preferably at least at least 10.0 mm, preferably at least 12.0 mm.

Advantageously, the length of the rectangular perforation or the length of the oval perforation is at most 30.0 mm, preferably at most 25.0 mm, preferably at most 20.0 mm, preferably at most at most 18.0 mm, preferably at most 15.0 mm, more preferably at most 14.0 mm, preferably at most 13.0 mm, preferably at most 12.0 mm.

In the context of the present application, the terms "length of the oval perforation" and "width of the oval perforation" denote respectively the dimension corresponding to the length and width of a rectangular perforation in which this oval would be inscribed.

Advantageously, the width of the rectangular perforation or the width of the oval perforation is at least 0.5 mm, preferably at least 0.75 mm, preferably at least 1.0 mm, preferably at least at least 1.2 mm.

Advantageously, the width of the rectangular perforation or the width of the oval perforation is at most 6.0 mm, preferably at most 5.0 mm, preferably at most 4.0 mm, preferably at most plus 3.0 mm, preferably not more than 2.5 mm, more preferably not more than 2.0 mm, preferably not more than 1.5 mm, preferably not more than 1.2 mm.

It is understood that one skilled in the art uses the optimal size of perforations of the device provided with a perforated screen of step 2, this size being adapted to the type of cultivated grain used and resulting from step 1.

For example, in the case of corn kernels, the length of the rectangular or oval perforation is advantageously between 5.0 mm and 18.0 mm, preferably between 7.0 mm and 15.0 mm, more preferably between 10 mm and 15.0 mm. , 0 mm and 14.0 mm.

Still in the case of corn kernels, the width of the rectangular or oval perforation is advantageously between 0.5 mm and 5.0 mm, preferably between 0.75 mm and 3.0 mm, more preferably between 1.0 mm and 2.0 mm.

The device provided with a perforated screen may for example be in the form of a filter sleeve.

In an advantageous embodiment of the process of the present invention, step 1 and step 2 of the process can be carried out in the same processing unit. In this case, the processing unit used in step 1 may for example comprise a device provided with a perforated screen.

In a particularly advantageous embodiment of the present invention, optionally packaged grains are subjected to step 1 and step 2 in an MHXM machine from Bühler.

In an alternative embodiment of the process according to the invention, in step 2, the grains, once treated according to step 1 of the process according to the invention and optionally packaged, are then separated into two fractions, according to one or threshold values of density. More specifically, the grains are separated into a first grain fraction (Fi) comprising first grain fragments having a density greater than a predetermined threshold density value and a second grain fraction (F2) comprising second grain fragments exhibiting a specific grain size. density less than a predetermined threshold value of density.

Among the methods for density separation, centrifugation and suction separation may be mentioned.

In one embodiment of the process of the present invention, the second grain fraction (F2) is directly collected after step 2.

In an alternative embodiment, the second grain fraction (F2) is sucked out of the perforated screen device by a suction channel to be collected in a space separate from the space in which step 2 occurs.

Optionally, the second fraction of grains (F2) preferably circulates through a cyclone after its exit from step 2 and before being collected.

In an advantageous embodiment of the present invention, the grain fraction (F 2) represents at most 50% by weight, preferably at most 45% by weight, preferably at most 40% by weight, more preferably at most 35% by weight. weight relative to the total weight of whole grains.

In an advantageous embodiment of the present invention, the grain fraction (F2) represents at least 15% by weight, preferably at least 20% by weight, preferably at least 25% by weight relative to the total weight of whole grains. .

In an advantageous embodiment of the present invention, the corn (F2) grain fraction represents at most 45% by weight, preferably at most 40% by weight relative to the total weight of whole grains.

In an advantageous embodiment of the present invention, the grain fraction (F 2) of maize represents at least 15% by weight, preferably at least 20% by weight, preferably at least 25% by weight relative to the total weight of the whole grains.

The fraction (F2) can optionally be used as animal feed. In step 3 of the process according to the invention, a second separation is carried out on said first fraction of grains (F1) obtained in step 2, so as to isolate said fraction of grains (F) having said content of reduced iron. More particularly, a separation carried out on the basis of size and / or shape is carried out according to this third step of the process according to the invention: the first fraction of grains (F1) is separated into at least two fractions, the fraction of grains (F) obtained at the end of this step 3 being one of these at least two fractions.

In a particularly advantageous embodiment of the present invention, the separation of the first grain fraction (F1) from step 3 comprises a mechanical separation.

In a particular embodiment of the present invention, the separation of step 3 is sieving separation. Separation by sieving can for example take place in a separator type machine. Advantageously, the mechanical sieving can be carried out using one or a set of sieves having meshs of different sizes.

Sieves can be arranged in different ways. Among other things, the screens may be vertically superimposed, or successively aligned along an inclined slope, or positioned in a combination of these two arrangements.

It is understood that the sieve having the largest mesh size will be located in an upper position, the screens being positioned by mesh size decreasing from top to bottom. The screen with the smallest mesh size is therefore in the lower position.

Advantageously, the sieve assembly comprises from 2 to 7 sieves, preferably from 2 to 6 sieves, preferably from 2 to 5 sieves, preferably from 2 to 4 sieves, more preferably from 2 to 3 sieves, preferably 2 sieves.

In a preferred embodiment of the present invention, the mesh size of the sieve in the lower position is at least 500 μm, preferably at least 750 μm, preferably at least 1000 μm, preferably at least 500 μm. at least 1100 μm, preferably at least 1200 μm, preferably at least 1300 μm, more preferably at least 1400 μm, preferably at least 1500 μm.

In addition, it is understood that the mesh size of the sieve in the upper position is at most 10 000 μm, preferably at most 9000 μm, preferably at most 8000 μm, preferably at most 7000 μm. pm, preferably at most 6000 pm, preferably at most 5600 pm.

Alternatively, a single sieve could be used instead of a set of sieves.

In the case where a single sieve is used, the mesh size of this sieve is at least 500 μm, preferably at least 750 μm, preferably at least 1000 μm, preferably at least 1100 μm. pm, preferably at least 1200 pm, preferably at least 1300 pm, more preferably at least 1400 pm, preferably at least 1500 pm.

In step 3 of the process of the present invention, the first grain fraction (F1) is separated into at least two fractions, as indicated above. An intermediate grain fraction [hereinafter called grain fraction (F ')] can be collected between the sieve in the lower position and the sieve in the upper position, if said sieve in the upper position is present, or on the sieve in the lower position. if only one sieve is used. The fraction having passed through the sieve assembly, specifically the lower sieve as described above, is referred to as the grain fraction (F3).

The fragments that have not passed through the sieve in the upper position, if it is present, form a fraction comprising the fragments of size greater than the size of the sieve meshes in the upper position.

The grain fraction (F) as described above can be obtained by subjecting the fraction (F ') to a subsequent separation step, so as to subtract a fraction of grains (F4).

In the context of the present invention, the inventors have found that the grain fraction (F4) generally comprises the grain envelopes and the seeds of the small grains. It is well known that grain envelopes may contain mycotoxins. Typically, mycotoxins are undesirable because they can cause acute food poisoning, infertility, and / or other metabolic disorders, especially in livestock.

That said, the inventors have surprisingly found that the grain fraction (F) obtained according to the process of the invention has a reduced concentration of mycotoxins. The term "reduced concentration of mycotoxins" corresponds in the context of the present application to a concentration of mycotoxins reduced by at least 30% compared to the initial mycotoxin concentration.

In an advantageous embodiment of the process of the present invention, the subsequent separation step for subtracting a grain fraction (F4) from the grain fraction (F) can be carried out using aspiration means. An example of suction means is an air suction channel.

In a particular embodiment of step 3 of the process of the present invention, the grain fraction (F) is obtained using a separator type machine.

Among the separator-type machines that can be used in step 3 according to the invention, mention may be made of the MTRA and MTRB machines, both from Bühler GmbH.

The different grain fractions (F), (F3) and (F4) can be collected and their percentage proportions by weight based on the total weight of whole grains can be calculated.

In the process of the present invention, the grain fraction (F) advantageously represents at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight relative to the total weight of the whole grains.

In the process of the present invention, the grain fraction (F) advantageously represents at most 80% by weight, preferably at most 75% by weight, preferably at most 70% by weight relative to the total weight of whole grains.

In the process of the present invention, the grain fraction (F3) advantageously represents less than 10% by weight, preferably less than 8% by weight, preferably less than 5% by weight based on the total weight of whole grains.

When present, the grain fraction (F4) advantageously represents less than 8% by weight, preferably less than 5% by weight, preferably less than 3% by weight relative to the total weight of whole grains.

A specific embodiment of step 3 is described in the experimental part.

The fraction of grains (F)

In one embodiment of the present invention, the grain fraction (F) as described above is obtained by the method described above. The grain fraction (F) is also an aspect of the present invention.

It is further understood that all the definitions and preferences described above apply equally to this embodiment, as well as to the other embodiments described below.

The inventors have found, surprisingly, that the grain fraction (F) of the present invention has a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably at least 35% by weight, preferably at least 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight, more preferably at least 60% by weight relative to the initial iron content of the whole grain.

For the purposes of the present invention, it is understood that the iron content in the grain fraction (F) is at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least minimum of 2.5 mg / kg.

Typically, whole corn kernels have an iron content ranging from 10.0 mg / kg to 50.0 mg / kg, depending on the variety.

In a preferred embodiment of the present invention, the corn (F) grain fraction has a reduced iron content relative to the initial iron content of the whole corn kernel. The iron content of the corn (F) grain fraction may be at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least 2.5 mg / kg. kg.

In addition, the iron content of the grain fraction (F) of maize is at most 30.0 mg / kg, preferably at most 25.0 mg / kg, preferably at most 20.0 mg / kg. more preferably at most 15.0 mg / kg, preferably at most 13.0 mg / kg, preferably at most 12.5 mg / kg, more preferably at most 12.0 mg / kg.

In the context of the present invention, it has been surprisingly determined that the grain fraction (F), obtained from whole grains subjected to the process according to the invention, comprises grain fragments whose content content fat is reduced but adequate for animal feed. By the term "reduced but adequate", it is understood that the fat content of the grain fraction (F) is reduced by about 25% to 85% with respect to the initial fat content.

The fat content of the grain fraction (F) can for example be measured by the Soxhlet method and can be expressed in mg / kg or in percentage.

Typically, a whole grain of corn has an initial fat content of 4 to 5%.

In a preferred embodiment of the present invention, the maize grain fraction (F) resulting from the process of the present invention has a fat content of at least 0.5%, preferably at least 1, 0%, preferably at least 1.5%, preferably at least 2.0%.

The grain fraction (F) of corn resulting from the process of the present invention has a fat content of at most 4%, preferably at most 3%.

Good results have been obtained for a fat content in the range of 2% to 3% in the grain fraction (F) of maize.

The fat content values of the grain fraction (F) are also applicable to the processed products of said grain fraction (F), as explained in detail below.

In the context of the present invention, it has surprisingly been determined that the grain fraction (F), obtained from whole grains subjected to the process according to the invention, comprises grain fragments whose starch content is increased but adequate for animal feed. By the term "increased but adequate", it is understood that the starch content of the grain fraction (F) is increased by at least 3% by weight, preferably by at least 4% by weight, preferably by at least 5% by weight, more preferably at least 6% by weight, preferably at least 8% by weight relative to the starch content of whole grains used in step 1 of the process according to invention. It is also understood that the starch content of the grain fraction (F) is increased by at most 25% by weight, preferably by at most 20% by weight, preferably by at most 15% by weight, preferably of at most 10% by weight, more preferably at most 8% by weight relative to the starch content of the whole grains used in step 1 of the process according to the invention. This is particularly unexpected since the whole grains can be subjected, according to the invention, to various constraints such as grinding, cleaning, moistening or polishing. However, despite these various treatments and despite the various process steps to which whole grains and grain fractions derived from them are subjected, an increased starch content is observed for the grain fraction (F) with respect to the starch content of the grains. whole grains. This is particularly advantageous since the starch content of the whole grains but also of the grain fraction (F) obtained is adequate in terms of the nutrition of the farm animals and in particular the beef calves.

The starch content of the grain fraction (F) can for example be measured by Ewers method or enzymatic method and can be expressed in mg / kg or in percentage. The method protocol WV.FD.21 EG 152/2009 of the European Commission can for example be used.

The corn grain fraction (F) resulting from the process of the present invention has a starch content of at least 68%, preferably at least 69%, preferably at least 70%, more preferably at least 70%, preferably less 71%.

The grain fraction (F) of corn resulting from the process of the present invention has a starch content of at most 85%, preferably at most 80%, preferably at most 75%.

The starch content values of the grain fraction (F) are also applicable to the transformed products of said grain fraction (F), as explained in detail below.

The energy value of the grain fraction (F) is the amount of energy that can be removed, for example during digestion. The energy value is evaluated and calculated on the basis of all energy nutrients, namely starch, sugars, other carbohydrates, fats and proteins. This energy value can be measured by calorimetric bomb and can be expressed in kJ / kg or kcal / kg.

Typically the gross energy value of an entire corn kernel is between 4400 kcal / kg and 4600 kcal / kg.

In a preferred embodiment of the present invention, the maize grain fraction (F) resulting from the process of the present invention has an energy value of at least 3500 kcal / kg, preferably at least 4000 kcal / kg. preferably at least 4300 kcal / kg.

The grain fraction (F) of corn resulting from the process of the present invention has an energy value of at most 5000 kcal / kg, preferably at most 4500 kcal / kg.

According to the present invention, it has been determined that the method implemented makes it possible to maintain the energy value of a maize grain at a substantially constant level between the whole grain and the grain fraction (F).

The energy value of the grain fraction (F) is also applicable to the processed products of said grain fraction (F), as explained in detail below.

In the context of the present invention, it has been found that the reduction in the fat content is counterbalanced by the increase in the starch content. Thus, the grain fraction (F) maintains a good balance between the fat content and the starch content, and therefore, good nutritional properties, as well as a good energy value.

In one embodiment of the process of the present invention, the grain fraction (F) has a particle size distribution such that:

Dg -1 1000 pm and Dg + 6000 pm and Dggs <7000 pm

In an alternative embodiment of the process of the present invention, the grain fraction (F) has a particle size distribution such that:

Dg -1 500 pm and Dg 4 4000 pm and Dggs <5000 pm

In another alternative embodiment of the process of the present invention, the grain fraction (F) has a particle size distribution such that:

In an advantageous embodiment of the invention, the particles of the maize grain fraction (F) have a particle size of one or more of a particle size of one or more than one. the following particle size distributions:

D 1000 1000 1000 μm and Dgo ^ 6000 μm and Dgg.s.s 7000 μm; or D 600, 1200 μm, and D 6000, 6000 μm and D max, 7000 μm; or Dg at 1400 .mu.m and D 6000 at 6000 .mu.m and D max at 7000 .mu.m.

In a preferred embodiment of the present invention, the particles of corn grain fraction (F) have a particle size in one of the following particle size distributions:

D 10 pm 1900 μm and D 0.85 μm and D 50 35 3500 μm; or D max 1900 μm and D max 4750 μm and D 50 3000 3000 μm; or λ max 1900 μm and D max 4750 μm and D 50 28 2884 μm.

For the purposes of the present invention, a particle size distribution of the grain fraction (F), in particular the grain fraction (F) of maize, expressed by D, "Y denotes a percentage (xx%) by weight of the fraction of grains (F) having a particle size of less than or equal to Y.

For example, D 1000 1000 1000 μm means that 90% by weight of the particles of the grain fraction (F), in particular the grain fraction (F) of maize, have a particle size greater than or equal to 1000 μm.

In the context of the present invention, the particle size distribution of the grain fraction (F), in particular the grain fraction (F) of maize, can be determined by any appropriate means, inter alia by dynamic light scattering and by mechanical sieving, preferably by mechanical sieving. The mechanical sieving analysis is typically based on the mechanical separation of different subfractions of the grain fraction (F), in particular the grain fraction (F) of corn, on a series of superposed sieves.

The values D50, D90 and D99 can be calculated from the percentages by weight of the subfractions obtained in each sieve relative to the total weight of the grain fraction (F). This calculation is carried out as follows: 1) Calculation of the percentage by weight of particles retained on each sieve 2) Expression of the cumulative weight percentage passing through each sieve

A typical particle size analysis method is described in detail in the experimental section.

According to the invention, it has been found, surprisingly, that the fraction of grains (F) resulting from the process of the present invention systematically has a reduced iron content of at least 25% by weight relative to the initial iron content. whole grains, while having a fat content reflecting good nutritional properties, good digestibility and good palatability.

In addition, surprisingly, despite the stresses to which whole grains and / or grain fractions are subjected, it has been shown, in the context of the present invention, that the fat content has been reduced. reduced and starch content increased, while maintaining good nutritional properties and good energy value.

Processed products

The grain fraction (F) obtained according to the invention can be transformed using known transformation methods, which are also an aspect of the present invention. Among the known transformation processes, grinding, flattening, flaking, toasting, extrusion, granulation, micronization or expansion can be mentioned.

Transformed products resulting from said transformation processes are also an aspect of the present invention. Among the processed products, mention may be made of flakes, flours, extrudates, granules, expanded products, micronised products and toasted products.

In one embodiment of the process of the present invention, the fragments forming the grain fraction (F) are subjected to a flaking process, in which the optionally moistened and / or cooked grains are flattened and flaked. The flakes of the present invention may be prepared according to a plurality of methods well known to those skilled in the art and described in the state of the art, as for example in the document US 558393, the entire contents of this application being incorporated herein by reference for all purposes.

The inventors have found, surprisingly, that after flaking, the iron content is not significantly changed, but may even be slightly reduced. The flakes of the present invention have a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably at least 35% by weight, preferably at least 40% by weight. % by weight, preferably at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight, more preferably at least 60% by weight relative to the content in initial iron of the whole grain.

It is understood that the iron content in corn flakes is at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least 2.5 mg / kg.

Typically, whole corn kernels have an iron content ranging from 10.0 mg / kg to 50.0 mg / kg, depending on the variety.

In a preferred embodiment of the present invention, the corn grain flakes have a reduced iron content relative to the initial iron content of the whole corn kernel. The iron content of the corn flakes may be at least 1.0 mg / kg, preferably at least 2.0 mg / kg, preferably at least 2.5 mg / kg.

In addition, the iron content of the corn flakes can be at most 30.0 mg / kg, preferably at most 25.0 mg / kg, preferably at most 20.0 mg / kg, more preferably at most. 15.0 mg / kg, preferably at most 13.0 mg / kg, preferably at most 12.5 mg / kg, more preferably at most 12.0 mg / kg.

Use of the grain fraction (F) and / or the transformed products The use of the grain fraction (F) and / or the transformed products from the grain fraction (F) is also an aspect of the present invention.

In one embodiment of the present invention, the processed products can be used in a variety of application fields, such as brewery, fermentation alcohol production, agri-food, bakery, and the like. animal feed.

Among the applications in the brewery, mention may be made of the use of the fraction of grains (F) or of the products transformed from the fraction of grains (F) in the manufacture of beer.

Among the applications in the field of the production of fermentation alcohol, mention may be made of the use of the fraction of grains (F) or of the products transformed from the fraction of grains (F) in the manufacture of alcohols, particularly alcohols such as juniper, gin, sake, whiskey, or different types of schnapps.

Applications in the agri-food and bakery industries include the use of grain fraction (F) or processed products from the grain fraction (F) in the manufacture of sweet snacks. or salty ones such as cereal bars or breakfast cereals, sweet biscuits, cookies, breads, cakes or pastries.

Among the applications in the field of animal feed, mention may be made of the use of the grain fraction (F) or of the processed products from the grain fraction (F) in the manufacture of solid type foods intended for animals such as farm animals, domestic animals, birds, fish or insects.

An animal feed product comprising the grain fraction (F) or processed products from the grain fraction (F) is also an aspect of the present invention.

Compound used in the composition of animal feed

The compound derived from the grain fraction (F) used in the composition of an animal feed is also an aspect of the present invention.

The present invention is described with particular embodiments but the invention is not limited by them.

Experimental part The invention will be described in detail in the following example, whose purpose is purely illustrative and does not limit the scope of the invention.

General method for obtaining the fraction (F) according to the invention

A grain fraction (F) was obtained by subjecting whole corn kernels to the process of the present invention.

Two different types of corn kernel, named CREIL and SW, were used, as shown in Tables 1 and 2. The respective initial iron contents of the CREIL and SW corn kernels are shown in Table 2.

A total of 9 samples were prepared and analyzed. Of these 9 samples, 5 were obtained from SW type maize and 4 were obtained from CREIL type maize.

Whole grains were first packaged. The package includes a cleaning with a flow of air circulating in a separator MTRA and MTRC cleanser, then a humidification by adding 1% water, for about 90 seconds.

The whole grains thus packaged were then treated by abrasion (step 1 according to the invention) carried out in an MXHM machine of the Bühler company.

The grains thus treated were then separated into two fractions, respectively (Fi) and (F2) according to their particle size. The separation step was carried out in a device provided with a perforated screen also included in the Bühler MXFIM machine. The perforations define the particle size threshold value separating fraction (F1) from fraction (F2). Said perforations are oval and have a width of 1.2 mm and a length of 12 mm. The crushed grains were introduced into said device provided with a perforated screen.

The fragments passing through the perforated screen, having a particle size smaller than the threshold value, represent the fraction (F2).

The fragments retained on the perforated screen, having a particle size greater than the threshold value, represents the fraction (F1).

The fraction (F2) was sucked by a suction channel out of the MXHM machine and then circulated through a cyclone before being collected.

The fraction (F1) was directed to an MTRB separator from the Bühler company in which it underwent a new separation (step 3). Step 3 was performed by adjusting the machine according to the parameters summarized in Table 1.

As indicated in Table 1 and according to this example, three grain fractions (F, F3 and F4) are obtained in step 3.

In the case of samples 1 to 6, the separator MTRB comprises two screens arranged one above the other. Fraction (F1) was introduced from the top of the separator and was evenly distributed over the upper sieve, having mesh sizes of 7000 μm, to be separated from fragments larger than 7000 μm or larger. remaining impurities of large size. Large impurities may for example designate strands of straw, grains remaining whole.

In the case of samples 7, 8 and 9, the upper sieve has been removed, the MTRB has the lower sieve only.

Fragments of fraction (F1) having optionally passed through the upper sieve were then all distributed over the lower sieve having mesh sizes of 1500 μm. Fragments that passed through the lower sieve were pooled into a fraction (F3) whose fragments had a particle size of less than 1500 μm and which was collected.

The remaining fragments, having a particle size between 1500 pm and 7000 pm, were introduced into an air suction channel for a subsequent separation step, during which the lighter, lighter density fragments were directed to the top of the air intake channel to form the fraction (F4), which was collected. The remaining fragments, forming fraction (F), were sent down and collected.

The different parameters of the separator MTRB and the proportions of fractions (F1) (grouping the fractions (F), (F3) and (F4)) and (F2) have been recorded in Table 1 below.

The iron and fat content of the various fraction samples (F) was measured, and the results were recorded in Table 2 below. Details of the methods for analyzing iron and fat content are specified below.

Table 1: Process parameters and fraction proportions collected

(*% by weight relative to the total weight of whole grains)

Table 2: Iron content and fat content of fraction (F)

'Percentage by weight' percentage by weight of fat with respect to the total weight of the fraction (F)

Granulometric analysis of fraction (F) was also performed. The details of the particle size analysis methods are specified below.

The grain fraction samples (F) were then flattened and flaked.

All samples were soaked in water for 8 hours and then boiled in water for one hour. The samples were then passed between two adjacent cold rollers rotating in opposite directions, in order to flatten the fragments of the grain fractions (F).

The samples were then baked in an oven until the resulting flakes became dry. The iron content and the fat content of the flakes obtained from the 9 samples were measured according to the methods of analysis of iron content and fat content described below. For all the samples, the iron content remained unchanged with respect to the iron content of the corresponding fractions (F). Method of analysis of the iron content

The iron contents of the various grain fraction (F) and flake samples were measured by inductively coupled plasma spectroscopy. The samples were prepared as follows. 1000 mg of the grain fraction (F) or flakes were milled, then digested with 65% suprapur nitric acid in nanopure water, in a MLS TurboWave microwave digestion system, at a temperature of 260 ° C. The samples were then introduced into the inductively coupled plasma spectroscopy of the brand Varian Vista MPX axial, using the "Quant Fe 0-10 mg / L" mode. Method of Analysis of the Content of the Scale Material Analysis of the fat content requires grinding of the samples. Since grinding can cause water loss, the water content of the samples has previously been determined. The water content was measured according to standard method ICC No. 110/1, at 130 ° C. for 90 minutes, with a thermogravimetric analysis apparatus TGA 701 from LECO corporation.

Each sample was milled using a Retsch ZM200 ultracentrifugal mill equipped with a 0.5 mm conidur screen, and homogeneous samples were prepared. The fat content of each sample was determined according to the Soxhlet Total Fat Method, with a reproducibility of ± 0.1%.

Granulometric analysis of fraction (F)

The grain fraction (F) was analyzed using the "Universal Laboratory Sifter" sieving device from Bühler. 250g of samples were placed in the sieving device and subjected to an eccentric movement for 5 minutes at a speed of 165 revolutions per minute (rpm).

This device comprises 7 screens, the latter having respectively meshes having the following dimensions: 1500 pm, 1900 pm, 2884 pm, 3350 pm, 4000 pm, 4750 pm and 5600 pm, in order to determine the particle size distribution of the various samples. The results are shown in Table 3 below.

Table 3: Particle size distribution of the fraction (F)

It is understood that the present invention is in no way limited to the embodiments described above and that many modifications can be made without departing from the scope of the appended claims.

Claims (29)

claims A process for obtaining, from whole grains selected from the group consisting of at least one cereal grain, at least one oleaginous grain, at least one legume grain and a mixture of the latter, a fraction of grains (F) having a reduced iron content of at least 25% by weight relative to an initial iron content of said whole grains, said process comprising the following steps: Step 1: a step for treating said whole grains, Step 2: a step of separating said grains treated in step 1 so as to obtain a first grain fraction (Fi) comprising first grain fragments having a particle size greater than one or more predetermined particle size threshold values and a second grain fraction (F2) comprising second grain fragments having a particle size smaller than said predetermined threshold value (s) particle size, and Step 3: a step of separating said first grain fraction (FO obtained in step 2, based on te teille and / or the form of said first fragments, so as to isolate said fraction of grains (F) having said reduced iron content, 2. The process according to claim 1, wherein the grain fraction (F) has a reduced iron content of at least 40% in pools, preferably at least 45% by weight, preferably at least 50% by weight. % by weight, preferably at least 55% by weight, preferably at least 60% by weight relative to the initial iron content of the whole grain. 3. The method of claim 1 or 2, wherein said grain fraction (P) is obtained from whole grains being maize grains. The method of claim 3, wherein said grain fraction (F) obtained from whole grains being corn kernels has a maximum reduced iron content of 30.0 mg / kg, preferably a reduced iron content. 25.0 mg / kg, preferably a maximum reduced iron content of 20.0 mg / kg, more preferably a maximum reduced iron content of 15.0 mg / kg, preferably a maximum reduced iron content of 13. , 0 mg / kg, preferably a reduced maximum iron content of 12.5 mg / kg, more preferably a reduced maximum fat content of 12.0 mg / kg, 5. A process according to any one of the preceding claims, wherein said grain fraction (F) has a particle size distribution such that: D 1000 μm and D 6000 μm and D 90.5 s 7000 μm. The method of any of the preceding claims, wherein said step 1 of whole grain processing means fragmentation performed by grinding, friction treatment and / or abrasive treatment of whole grains. The method of any of the preceding claims, wherein step 1 is preceded or followed by a grain conditioning step. The method of claim 7, wherein said grain conditioning step comprises one or more cleaning steps, one or more moistening steps, and / or one or more polishing steps. 9. Method according to any one of the preceding claims, wherein said step 2 of separation is performed by means of a device provided with a perforated screen whose perforations have a rectangular or oval shape. The method of claim 9, wherein said perforations having a rectangular or oval shape having a length of not less than 3.0 mm, preferably not less than 5.0 mm, preferably not less than 7, 0 mm, preferably not less than 10.0 mm, preferably not less than 12.0 mm, said length not being greater than 30.0 mm, preferably not more than 25.0 mm, preferably not more than 20.0 mm, preferably not more than 18.0 mm, preferably not more than 15.0 mm, preferably not more than 14.0 mm, preferably not more than at 13.0 mm, preferably not more than 12.0 mm. The method according to claim 9 or 10, wherein said perforations having a rectangular or oval shape having a width of not less than 0.5 mm, preferably not less than 0.75 mm, preferably not less than 1.0 mm, preferably not less than 1.2 mm, said width not being greater than 6.0 mm, preferably not more than 5.0 mm, preferably not more than 4.0 mm, preferably not more than 3.0 mm, preferably not more than 2.5 mm, preferably not more than 2.0 mm, preferably not more than 1.5 mm, preferably not more than 1.2 mm. 12. Process according to any one of the preceding claims, in which said grain fraction (F2) represents at most 50% by weight, preferably at most 45% by weight, preferably at most 40% by weight, preferably at most plus 35% by weight relative to the total weight of whole grains. Process according to any one of the preceding claims, in which the fraction (F 2) represents at least 15% by weight, preferably at least 20% by weight, preferably at least 25% by weight relative to the total weight of the whole grains. The method of any of the preceding claims, wherein separating the first fraction (F ") of step 3 comprises mechanical separation. The method of claim 14, wherein said mechanical separation is performed using a screen or a plurality of screens having different size mesh. 16. The method of claim 15, wherein an intermediate grain fraction [hereinafter called grain fraction (P)] is collected between a sieve in the lower position and a sieve in the upper position, if said sieve in the upper position is present. , or on the sieve in the lower position if only one sieve is used. The method of claim 16, wherein said grain fraction (F) is obtained by subjecting the fraction (F ') to a subsequent separation step by subtracting a grain fraction (F4), 18. The method of claim 17, wherein said subsequent separating step is performed by means of aspirations. 19. The method of claim 15 wherein a grain fraction (F3) is collected after passing through all the sieves, specifically after passing through a sieve in the lower position. 20. Process according to any one of the preceding claims, in which the grain fraction (F) represents at most 80% by weight, preferably at most 75% by weight, preferably at most 70% by weight relative to the total weight. whole grains. 21. Process according to any one of the preceding claims, in which the fraction of grains (F) represents at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight relative to the weight. total whole grains. 22. Fraction of grains (F) obtained according to the method of any one of claims 1 to 21. 23. A process for converting a fraction of grams (F) obtained according to the process of claims 1 to 21 to obtain a transformed product. 24. The process of claim 23, wherein a step selected from the group consisting of milling, flattening, toasting, milling, extruding, granulating, micronizing and expanding is carried out. 25. Product transformed according to the transformation process according to claims 23 and 24, said transformed product having a reduced iron content of at least 25% by weight, preferably at least 30% by weight, preferably from less than 35% by weight, preferably 40% by weight, preferably at least 45% by weight, preferably at least 50% by weight, preferably at least 55% by weight, preferably at least 60% by weight based on the initial iron content of the whole grain. 26. Processed product according to claim 25, said processed product being a flake, an extrudate, a granule, a micronised product, a toasted product or an expanded product. 27. Use of the fraction (F) according to any one of claims 20 to 22 in the field of brewery, the production of fermentation alcohol, the field of agri-food, bakery, and / or the animal feed. 28. Use of the processed product according to the processing method according to claims 23 or 24 in the field of brewery, fermentation alcohol production, agro-processing field, bakery, and / or animal feed . 29. Compound derived from the fraction of grains (F) used in the composition of animal feed.