INSECT TREATMENT METHOD COMPRISING THE SEPARATION OF CUTICLE FROM THE SOFT PART OF THE INSECTS AND THEN THE SEPARATION OF THE SOFT PART INTO THREE FRACTIONS

Abstract

The invention relates to a method for processing insects comprising separating the cuticles from the soft parts of the insects, and then separating the soft parts of the insects into an oily fraction, a solid fraction, and an aqueous fraction. The invention further relates to powders, in particular a powder obtainable by the insect processing method according to the invention, and the use of these powders in food.

Description

Advantageously, the maturation is carried out for a period of between 15 minutes and 3 hours, preferably for 1 hour. Advantageously, maturation is carried out at a temperature between 65 and 100°C, preferably between 85 and 100°C, more preferably at a temperature of about 90°C. This step makes it easier to separate the soft part of the insects in step 4 below. Preferably, the process according to the invention includes such a step. In particular, no dilution of the soft part of the insects in a solvent such as water is necessary in this step. • Step 4: Separation of the soft part into a solid fraction, an aqueous fraction and an oily fraction The aim of this step is to recover three fractions from the soft part of the insects obtained in step 2 or 3, namely a solid fraction, an aqueous fraction, and an oily fraction. According to a first embodiment, this step of separating the soft part is carried out in two sub-steps. In the first sub-stage, the soft part of the insects is subjected to decantation using a 2-phase decanter, so as to obtain a solid fraction and a liquid fraction. In the second sub-step, the liquid fraction is subjected to centrifugation, so as to recover an oily fraction and an aqueous fraction. Advantageously, in this second sub-step, a plate centrifuge is used. According to a second embodiment of step 4, the soft part of the insects is subjected to decantation using a 3-phase decanter, so as to directly obtain an aqueous fraction, an oily fraction and a solid fraction. Suitable 3-phase decanters include, for example, the Tricanter® from Flottweg, or the 3-phase decanters from GEA, such as the CA 225-03-33 decanter. Advantageously, the separation of the soft part is carried out according to the second embodiment. Indeed, the use of a 3-phase decanter allows for particularly efficient phase separation. More specifically, the resulting solid fraction has a high dry matter content, the aqueous fraction contains little insoluble sediment (from the solid fraction) and oil, and the oily fraction contains little insoluble sediment (from the solid fraction) and water. • Step 5: Concentration of the aqueous fraction The aqueous fraction obtained in step 4 is then optionally concentrated, to obtain a concentrated aqueous fraction. Advantageously, the concentration is achieved by evaporation. Advantageously, evaporation is carried out at a temperature between 30 and 100°C, preferably between 60 and 80°C. Preferably, evaporation is carried out at a pressure between 50 and 1013 mbars, preferably at 1013 mbars. Evaporation is preferably carried out over a period of between 5 and 20 minutes. The concentration is preferably carried out using a falling film evaporator, a rising-flood plate evaporator, or a thin-film evaporator. This type of standard equipment can be used without encountering fouling problems, thanks in particular to the low quantity of sediments present in the aqueous fraction. Generally, aqueous fractions cannot be concentrated above 42% dry matter, as they tend to gel (glue water) from this concentration. In the case of the present invention, the aqueous fraction comprises small soluble proteins (at least 45% of the soluble proteins in the aqueous fraction have a size of less than 550 g / mol, as described in more detail below), which makes it possible to avoid gelation and thus obtain an aqueous fraction with a high dry matter concentration (up to 70%) and a viscosity of less than 30000 cPs (centipoise). By "soluble proteins" we mean, among crude proteins, those which are soluble in an aqueous solution with a pH between 6 and 8, advantageously between 7.2 and 7.6. When the term "proteins" is used in this application, it refers to crude proteins. Preferably, the aqueous solution is a buffer solution with a pH between 6 and 8, advantageously between 7.2 and 7.6. Preferably, the buffer solution is a phosphate buffer NaCl solution, with a pH of 7.4 + / - 0.2. Furthermore, the aqueous fraction concentration step is doubly advantageous because it allows: - Steam savings: in the absence of concentration step 5, the water would have to be evaporated during drying step 7 described below, using a dryer with a higher specific steam consumption than a concentrator as described above; and - to avoid microbiological contamination, thanks to a reduction in volume and osmotic pressure due to the high dry matter concentration of the concentrated aqueous fraction. • Step 6: Mixing the concentrated aqueous fraction and / or cuticles with the solid fraction All or part of the cuticles obtained in step 2 and / or all or part of the concentrated aqueous fraction obtained in step 5 may optionally be mixed with the solid fraction obtained in step 4 to obtain a mixture. Advantageously, the mixture is homogenized to facilitate its subsequent processing. Examples of mixers that can be used include conical screw mixers, such as those from Vrieco-Nauta®, or pendulum mixers, such as those from PMS. It should be noted that on average, for one kilogram of solid fraction obtained, we obtain 500 to 650g of cuticles, for example about 550g, and 250 to 350g of aqueous fraction, for example about 300g. • Step 7: Drying of the solid fraction obtained in step 4 or of the mixture obtained in step 6 The solid fraction obtained in step 4 or the mixture obtained in step 6 can be dried to obtain a dry solid fraction or a dry mixture. Advantageously, drying is carried out using a disc dryer, a tubular dryer, a propeller dryer, a flash dryer, a thin film dryer or a spray dryer. Preferably, drying is carried out using a disc or tubular dryer. Suitable tubular dryers include those from the company Tummers. (Simon Dryers Technology). Suitable disc dryers include those from the company Haarslev. Drying can be carried out between 1 and 10 hours, preferably between 3 and 5 hours. Advantageously, drying is carried out at a temperature between 60 and 225 °C, preferably between 80 and 100 °C. Preferably, evaporation is carried out at atmospheric pressure. • Step 8: Grinding of the dry solid fraction or dry mixture obtained in step 7 After drying, grinding can be carried out and a powder is obtained. By "powder" we mean a composition in the form of particles. Preferably, the powder according to the invention is an insect powder, that is to say a powder prepared solely from insects and possibly water. A crusher such as a hammer mill or a cone crusher (such as the cone crushers (“Kek cone mills >>) from the company Kemutec) can for example be used. Advantageously, after this grinding, the particle size is less than 0.5 cm (the largest particle size observable with a microscope), preferably on the order of 1 mm. More specifically, the particle size is between 300 pm and 1 mm, and even more preferably between 500 and 800 pm. When the powder is ground to a particle size acceptable for human or animal consumption, it can be designated as "flour," and in particular "insect meal." "Particle size acceptable for human or animal consumption" refers to a particle size between 100 µm and 1.5 mm, preferably between 300 µm and 1 mm, and more preferably between 500 µm and 800 µm. Depending on whether optional steps 5 and / or 6 are implemented or not, different powders can be obtained, namely: - a powder resulting solely from the solid fraction (step 6 not implemented); - a powder resulting from the mixture of the solid fraction and all or part of the cuticles; - a powder resulting from the mixing of the solid fraction and all or part of the concentrated aqueous fraction; - a powder resulting from the mixture of the solid fraction, all or part of the cuticles and all or part of the concentrated aqueous fraction. The invention also relates to products resulting from the process according to the invention. The invention further relates to a solid fraction that can be obtained by the insect treatment process according to the invention. The invention also relates to a solid fraction comprising at least 71% by weight of protein and between 0.1 and 2% by weight of chitin, the percentages by weight being indicated on the total dry weight of the solid fraction. Preferably, the solid fraction comprises at least 73% by weight, more preferably at least 74% by weight, even more preferably at least 75% by weight of protein, the percentages by weight being indicated on the total dry weight of the solid fraction. Advantageously, the solid fraction comprises between 0.5 and 1.7% by weight of chitin on the total dry weight of solid fraction. Advantageously, the solid fraction comprises between 5 and 17% by weight of lipids, preferably between 10 and 15% by weight of lipids, on the total dry weight of the solid fraction. Preferably, the solid fraction comprises between 1 and 10% by weight, preferably between 2 and 6% by weight of ash, on the total dry weight of solid fraction. The method for determining ash content is well known to those skilled in the art. Preferably, the ash content was determined according to the method specified in Regulation (EC) No 152 / 2009 of 27 January 2009. In addition, the solid fraction preferably comprises between 5 and 15% by weight, more preferably between 7 and 13% by weight of carbohydrates on the total dry weight of the solid fraction. More specifically, the solid fraction preferably comprises at least 0.2% by weight, more preferably at least 0.3% by weight, even more preferably at least 0.35% by weight of trehalose on the total dry weight of the solid fraction. Furthermore, protein digestibility in humans and animals is strongly influenced by protein size. In animal nutrition, it is common practice to reduce protein size to facilitate digestion. This protein size reduction is generally achieved through hydrolysis processes (e.g., enzymatic), which are particularly expensive to implement. The solid fraction contains soluble proteins whose size is reduced enough to facilitate digestion in animals. Advantageously, at least 75%, preferably at least 80%, more preferably at least 85% of the soluble proteins in the solid fraction have a size less than or equal to 12400 g / mol. More specifically, at least 55%, preferably at least 60%, more preferably at least 65% of the soluble proteins in the solid fraction have a size less than 550 g / mol. The invention also relates to an aqueous fraction that can be obtained by the insect treatment process according to the invention. The invention further relates to an aqueous fraction comprising at least 48% by weight of protein, at least 2% by weight of trehalose, and having a lipid content of less than 7% by weight, the percentages by weight being indicated on the total dry weight of the aqueous fraction. Preferably, the aqueous fraction comprises at least 55% by weight, more preferably at least 60% by weight, even more preferably at least 65% by weight of protein, on the total dry weight of the aqueous fraction. Advantageously, the aqueous fraction comprises at least 2.5% by weight, more preferably at least 3% by weight of trehalose on the total dry weight of the aqueous fraction. Preferably, the aqueous fraction has a lipid content of less than 6% by weight, more preferably less than 4% by weight, even more preferably less than 2% by weight, on the total dry weight of the aqueous fraction. Advantageously, the aqueous fraction comprises between 5% and 20% by weight of ash, preferably between 7% and 15% by weight of ash on the total dry weight of the aqueous fraction. In addition, the aqueous fraction comprises less than 2% by weight of insoluble sediments, preferably less than 1% by weight of insoluble sediments, on the total weight of the aqueous fraction. The aqueous fraction does not contain chitin. Similar to the solid fraction, the aqueous fraction contains soluble proteins whose size is sufficiently reduced to facilitate digestion by animals. Advantageously, at least 90%, preferably at least 95%, more preferably at least 97% of the soluble proteins in the aqueous fraction have a size less than or equal to 12400 g / mol. More specifically, at least 45%, preferably at least 50%, more preferably at least 53% of the soluble proteins in the aqueous fraction have a size less than 550 g / mol. More specifically, the aqueous fraction has a dry matter content of between 5 and 15% by weight of the total weight of the aqueous fraction. When concentrated, the concentrated aqueous fraction has a dry matter content of between 55 and 75% by weight of the total weight of the concentrated aqueous fraction. The invention also relates to a concentrated aqueous fraction that can be obtained by the insect treatment process according to the invention, said treatment process then comprising the optional concentration step. The invention further relates to an oily fraction that can be obtained by the insect treatment process according to the invention. The invention also relates to a powder that can be obtained by the insect treatment process comprising the following steps: - the separation of the cuticles from the soft part of insects, - the separation of the soft part of insects into an oily fraction, a solid fraction and aqueous fraction, - optionally, the concentration of the aqueous fraction, - Optionally, mixing the solid fraction with: - all or part of the concentrated aqueous fraction; and / or - all or part of the cuticles, to obtain a mixture, - the drying of the solid fraction or mixture to obtain a dry solid fraction or a dry mixture, respectively; - grinding of the dry solid fraction or dry mixture. This insect treatment process may also include one or more of the characteristics described above. The invention relates more particularly to a powder that can be obtained by the process of preparing a powder, and in particular an insect powder, according to the invention, as described above. As indicated above, depending on whether the optional steps 5 and / or 6 of the insect treatment process according to the invention, namely the step of concentrating the aqueous fraction and the step of mixing all or part of the cuticles and / or all or part of the concentrated aqueous fraction with the solid fraction, is / are or is / are not implemented, and where applicable depending on the conditions of their implementation, different powders may be obtained. The invention further relates to a powder, and in particular an insect powder, comprising at least 71% by weight of protein and between 0.1 and 4% by weight of chitin, the percentages by weight being indicated on the total dry weight of powder. Preferably, this powder has a protein content greater than or equal to 72% by weight, more preferably greater than or equal to 74% by weight, even more preferably greater than or equal to 75% by weight, on the total dry weight of powder. More specifically, this powder has a chitin content of between 0.5 and 3% by weight, more preferably between 0.8 and 2% by weight, even more preferably between 0.8 and 1.7% by weight on the total dry weight of powder. Preferably, this powder comprises between 5 and 20% by weight, preferably between 7 and 17% by weight of lipids, on the total dry weight of powder. More specifically, this powder comprises between 1 and 10% by weight, preferably between 2 and 6% by weight of ash, on the total dry weight of powder. In addition, this powder preferably contains between 3 and 20% by weight of carbohydrates on the total dry weight of powder. More specifically, this powder preferably comprises at least 0.1% by weight, more preferably at least 0.2% by weight of trehalose on the total dry weight of powder. When optional steps 5 and / or 6 are not implemented, a powder, and in particular an insect powder, resulting solely from the solid fraction is obtained. This powder comprises at least 71% by weight of protein and between 0.1 and 2% by weight of chitin, the percentages by weight being indicated on the total dry weight of powder. Preferably, this powder has a protein content greater than or equal to 72% by weight, more preferably greater than or equal to 74% by weight, even more preferably greater than or equal to 75% by weight, on the total dry weight of powder. More specifically, this powder has a chitin content of between 0.5 and 1.7% by weight of chitin, on the total dry weight of powder. Preferably, this powder comprises between 5 and 17% by weight, preferably between 10 and 15% by weight of lipids, on the total dry weight of powder. More specifically, this powder comprises between 1 and 10% by weight, preferably between 2 and 6% by weight of ash, on the total dry weight of powder. In addition, this powder preferably contains between 5 and 15% by weight, more preferably between 7 and 13% by weight of carbohydrates on the total dry weight of powder. More specifically, this powder preferably comprises at least 0.2% by weight, more preferably at least 0.3% by weight, even more preferably at least 0.35% by weight of trehalose on the total dry weight of powder. When steps 5 and 6 of the process according to the invention are carried out, a powder resulting from the mixture of the solid fraction, all or part of the cuticles and all or part of the concentrated aqueous fraction can also be obtained. The invention therefore further relates to a powder, and in particular an insect powder, comprising at least 65% by weight of protein, at least 10% by weight of carbohydrates and between 0.1 and 2% by weight of chitin, the percentages by weight being indicated on the total dry weight of powder. Preferably, this powder has a protein content greater than or equal to 70% by weight, more preferably greater than or equal to 74% by weight, on the total dry weight of powder. More specifically, this powder has a chitin content of between 0.2 and 1.5% by weight, more preferably between 0.5 and 1.3% by weight, on the total dry weight of powder. Preferably, this powder has a carbohydrate content greater than or equal to 12% by weight, more preferably greater than or equal to 14% by weight, on the total dry weight of powder. More specifically, this powder preferably comprises at least 0.7% by weight, more preferably at least 0.9% by weight, even more preferably at least 1% by weight, and even more preferably at least 1.2% by weight of trehalose on the total dry weight of powder. Preferably, this powder comprises between 5 and 15% by weight, preferably between 7 and 13% by weight of lipids, on the total dry weight of powder. More specifically, this powder comprises between 3 and 10% by weight, preferably between 4 and 8% by weight of ash, on the total dry weight of powder. The residual moisture content of the powders according to the invention is between 2 and 15%, preferably between 5 and 10%, more preferably between 4 and 8%. This rate humidity can for example be determined according to the method from EC regulation 152 / 2009 of 27-01-2009 (103 °C / 4 h). Advantageously, the proteins in the powders according to the invention have a digestibility greater than or equal to 85% by weight on the total weight of crude proteins. Digestibility is pepsin digestibility measured by the method described in Directive 72 / 199 / EC. Preferably, digestibility is greater than or equal to 88%, more preferably greater than or equal to 92%. The invention further relates to the use of an aqueous fraction according to the invention, a concentrated aqueous fraction according to the invention, or powder comprising at least 65% protein, at least 10% by weight of carbohydrates and between 0.1 and 2% by weight of chitin according to the invention described above, as a flavoring, advantageously in animal feed. The invention also relates to the use of a powder according to the invention in food, preferably in animal feed. Other features and advantages of the invention will become apparent in the following illustrative examples, with reference to: Figure 1, which is a diagram illustrating the detailed insect treatment process according to the invention. EXAMPLE 1: Insect treatment method according to the invention Tenebrio molitor larvae were used. Upon receipt, the larvae can be stored at 4°C for 0 to 15 days in their rearing trays before slaughter without significant deterioration. The weight (age) of the larvae used varies, and consequently, their composition may also vary, as illustrated in Table 1 below: Biomass (insects) mg 23 35 58 80 108 154 Dry matter %* 34 34 34.2 37.9 39.6 39.5 Ash O / * / 0 1.59 1.52 1.6 1.75 1.67 1.43 Crude protein O / * / 0 22.6 22.2 22 23.2 23.1 23.2 Fat O / * / 0 6.62 6.88 7.98 10.3 10.9 11.7 * Percentages are expressed as dry weight on the wet weight of larvae. Table 1: Biochemical composition of Tenebrio molitor larvae according to their weight. • Step 1: Killing the insects The live larvae (+4°C to +25°C) are conveyed in a thick layer Insects between 2 and 10 cm in diameter are placed on a perforated belt (1 mm) and then transferred to a bleaching chamber. There, they are bleached with steam (nozzles or steam bed) at 98°C under forced ventilation, or with water at 92-95°C (spray nozzles), or in a combination of water and steam. The time spent in the bleaching chamber ranges from 5 seconds to 15 minutes, ideally 5 minutes. The temperature of the larvae after blanching is between 75°C and 98°C. • Step 2: Separation of the soft part of the insect cuticles The larvae, once blanched, are conveyed to the feed hopper of a belt separator, in order to separate the cuticles from the soft part of the larvae. Advantageously, the separation takes place immediately after slaughter so that the larvae do not have time to cool to room temperature. The belt separator used is a 601 belt separator from the Baader company. The diameter of the perforations in the drum is 1.3 mm. The soft part of the insects is collected in a tank. The cuticles are collected using a scraper knife. Determination of the amount of trehalose in the cuticles The amount of trehalose in the cuticles recovered in step 2 was measured as follows: Trehalose is analyzed by GC-MS. Temperature program: 150 °C, followed by a ramp at 10 °C / min up to 260 °C. After 5 minutes at this temperature, a ramp at 25 °C / min up to 310 °C is maintained at this temperature for 2 minutes. Injector temperature: 280 °C, interface temperature: 250 °C, split ratio: 10, injection volume: 1 pL. For example, a 30 m x 0.25 mm x 0.25 µm SH-RXI-5mS column is used. The sample preparation for analysis is carried out as follows: a precise quantity of the sample (between 10 and 300 mg) is weighed into a Falcon tube, 9.75 mL of methanol is added, along with 250 pL of an internal standard solution (myo-inositol, 25 pg / mL) in DMSO. The mixture is stirred at 80 °C for 10 minutes, 100 pL of BSTFA is then added, and the reaction mixture is stirred for a further 30 minutes at room temperature. 1 mL of acetonitrile is then added, and the prepared sample is injected into a GC-MS instrument. The measured quantity is 1.2 mg of trehalose per g of dry matter. • Step 3: Maturation of the soft part of the insects The soft part of the insects is left to rest in the recovery tank from step 2, under agitation for 1 hour and at a temperature of approximately 90°C. • Step 4: Separation of the soft part into a solid fraction, an aqueous fraction and an oily fraction The soft part is then separated into three fractions using a three-phase decanter. The decanter used is the Flottweg Tricanter® Z23. Conditions of separation: Flow rate: up to 500 kg / h; - Vt bowl: 4806 rpm (3000G); - Y min: 5% (1.4 t / mm). Three fractions are obtained at the end of this separation phase: an oily fraction, a solid fraction, and an aqueous fraction. These fractions exhibit the characteristics shown in Table 2 below: Dry Matter (%) Protein Oil Ash Carbohydrates Solid Fraction 56 74.1 12.9 4 10 Aqueous Fraction 10 57 4 9 23 Oil Fraction >99.5 <0.5 >99.5 <0.25 <0.25 * Average results calculated on several samples of each fraction, expressed as a percentage of dry matter Table 2: Characteristics of the oily fraction, the solid fraction and the aqueous fraction. Determination of the size of soluble proteins in the solid fraction and the aqueous fraction Preparation of the solid sample (solid fraction): 30 mg of the sample are solubilized in 1 L of mobile phase and filtered using the chromafil xtra PES-45 / 25 filter. Preparation of the liquid sample (aqueous fraction): 400 pL are solubilized in 1600 pL of the mobile phase and filtered using the Chromafil xtra PES-45 / 25 filter, just before injection. 1.5 mL of the sample thus prepared are centrifuged for 15 min at 12000 rpm (10625g). The conditions for implementing the chromatography (HPLC Nexera XR from Shimadzu) are as follows: the column used is a Superdex Peptide GL 10 / 300 (GE Healthcare), detection is carried out by a DAD detector at 215 nm, the mobile phase speed is 0.3 mL / min and it is composed of ACN (acetonitrile) / H2O / TFA (trifluoroacetic acid) (30 / 70 / 0.1), the analysis is carried out at 25 "G. The size distribution of soluble proteins in the solid fraction is shown in Table 3 below: Molecular weight (kDa) % > 12.4 13.8 12.4-6.5 14 6.5-1.4 3.8 1.4-0.55 2.1 <0.55 67.3 Table 3: Size distribution of soluble proteins in the solid fraction. The size distribution of soluble proteins in the aqueous fraction is presented in Table 4 below: Molecular weight (kDa) % >12.4 2.7 12.4-6.5 13.4 6.5-1.4 19 1.4 - 0.55 11.5 <0.55 53.4 Table 4: Size distribution of soluble proteins in the aqueous fraction Determination of the amount of trehalose in the solid fraction and the aqueous fraction The amount of trehalose in these fractions was measured as follows: Trehalose is analyzed by GC-MS. Temperature program: 150°C, followed by a ramp at 10°C / min up to 260 °C, after 5 minutes at this temperature, a ramp of 25 °C / min up to 310 °C and maintenance of this temperature for 2 minutes. Injector temperature: 280 °C, interface temperature: 250 °C, split ratio is 10, injection volume is 1 pL. The sample preparation for analysis is carried out as follows: a precise quantity of the sample (between 10 and 300 mg) is weighed into a Falcon tube, 9.75 mL of methanol is added, along with 250 pL of an internal standard solution (myo-inositol, 25 pg / mL) in DMSO. The mixture is stirred at 80 °C for 10 minutes, 100 pL of BSTFA is then added, and the reaction mixture is stirred for a further 30 minutes at room temperature. 1 mL of acetonitrile is then added, and the prepared sample is injected into a GC-MS instrument. The amount measured in the solid fraction is 3.82 mg of trehalose per g of dry matter. The amount measured in the aqueous fraction is 33.2 mg of trehalose per g of dry matter. In addition, the aqueous fraction contains less than 1% by weight of insoluble sediments relative to the total weight of the aqueous fraction. • Step 5: Concentration of the aqueous fraction The aqueous fraction obtained in step 4 is then concentrated by evaporation, using a falling-float evaporator. The concentrated aqueous fraction obtained has a dry matter concentration of approximately 65%. • Step 6 (optional): Mix the concentrated aqueous fraction and / or cuticles with the solid fraction Step 6 was not implemented in this example. • Step 7: Drying the solid fraction The solid fraction obtained in step 4 is dried using a Haarslev disc dryer for 5 hours to obtain a dry solid fraction or a dry mixture. From a microbiological point of view, the solid fraction contains less than 10 CFU / g of enterobacteria. • Step 8: Grinding The dry solid fraction is then ground using a continuous hammer mill (6 reversible hammers - 8 mm thickness). The mill is fed by a hopper with a flow rate adjustment gate (180 kg / h). The perforated screen used for The output particle size control is 0.8 mm. The motor rotation speed is 3000 rpm (electric motor, power consumption 4kW (5.5 HP)). The characteristics of an insect powder obtained are presented in Table 5 below. Proteins Chitin Ash Lipids Carbohydrates Trehalose 75.1% 1.3% 4% 12.5% ​​10% 0.38% * The percentages indicated are percentages by weight on the total dry weight of the insect powder. Table 5: Characteristics of an insect powder obtained in Example 1. EXAMPLE 2: Insect treatment method according to the invention Steps 1 to 5 were implemented as described in Example 1. • Step 6 (optional): Mix the concentrated aqueous fraction and cuticles with the solid fraction All (100%) of the concentrated aqueous fraction obtained in step 5, as well as 0.05% by weight of the cuticles recovered in step 2, were mixed with all of the solid fraction obtained in step 4, to obtain a mixture. A conical screw mixer from the company Vrieco-Nauta® was used. • Step 7: Drying the mixture The mixture obtained in step 6 is dried using a Haarslev disc dryer for 5 hours to obtain a dry mixture. From a microbiological point of view, the dry mixture contains less than 10 CFU / g of enterobacteria. • Step 8: Grinding The dry mixture is then ground using a continuous hammer mill (6 reversible hammers - 8 mm thickness). The mill is fed by a hopper with a flow rate adjustment gate (180 kg / h). The perforated screen used to control the output particle size is 0.8 mm. The motor speed is 3000 rpm (electric motor, power consumption 4 kW (5.5 hp)). The characteristics of an insect powder obtained are presented in Table 6 below. Proteins Chitin Ash Lipids Carbohydrates Trehalose 66% 1% 6% 11% 13% 1.1% The percentages shown are percentages by weight of the total dry weight of the insect powder. Table 6: Characteristics of the insect powder obtained in Example 2. 5 10

Claims

DEMANDS 1. Insect treatment process comprising the following steps: - the separation of the cuticles from the soft part of the insects, then - the separation of the soft part of the insects into an oily fraction, a solid fraction and an aqueous fraction.

2. A process according to claim 1, comprising a maturation step of the soft part of the insects, prior to the step of separating the soft part of the insects into an oily fraction, a solid fraction and an aqueous fraction.

3. A method according to any one of claims 1 or 2, wherein the separation of the cuticles from the soft part of the insects is carried out using a filter press.

4. A method according to any one of claims 1 or 2, wherein the separation of the cuticles from the soft part of the insects is carried out using a belt separator.

5. Solid fraction obtainable by the process according to any one of claims 1 to 4.

6. Solid fraction comprising at least 71% by weight of protein and comprising between 0.1 and 2% by weight of chitin, the percentages by weight being indicated on the total dry weight of the solid fraction.

7. A process according to any one of claims 1 to 4, comprising a step of concentrating the aqueous fraction.

8. Aqueous fraction comprising at least 48% by weight of protein, at least 2% by weight of trehalose, and having a lipid content of less than 7% by weight, the percentages by weight being indicated on the total dry weight of the aqueous fraction.

9. A method according to any one of claims 1 to 4, 7, further comprising a step of mixing the solid fraction with: - all or part of the concentrated aqueous fraction; and / or - all or part of the cuticles, to obtain a mixture.

10. A process according to any one of claims 1 to 4, 9, comprising a step of drying the solid fraction or the mixture to obtain a dry solid fraction or a dry mixture, respectively.

11. A process according to claim 10, further comprising a step of grinding the dry solid fraction or the dry mixture.

12. Powder comprising at least 71% by weight of protein and comprising between 0.1 and 4% by weight of chitin, the percentages by weight being indicated on the total dry weight of powder.

13. Powder comprising at least 65% by weight of protein, at least 10% by weight of carbohydrates and comprising between 0.1 and 2% by weight of chitin, the percentages by weight being indicated on the total dry weight of powder.

14. Use of an aqueous fraction according to claim 8, or of the powder according to claim 13, as a flavoring.

15. Use of a powder according to one of claims 12 or 13, in food.

16. Use according to one of claims 14 or 15, in animal feed.

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