Insect pulp and its manufacturing process

Abstract

The present invention relates to a process for preparing insect pulp, to the insect pulp thus obtained, and to its uses in animal feed, particularly feed for domestic animals. (Figure for the abstract: no figure)

Description

Title of the invention: Insect pulp and its manufacturing process TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a process for preparing insect pulp, to the insect pulp thus obtained and to its uses in animal feed and in particular in feeding domestic animals. Description of the invention

[0002] With increasing environmental concerns, the search for alternatives to conventional animal proteins is becoming increasingly important not only in human food but also in animal feed.

[0003] By usual animal proteins, we mean proteins from animals raised for cattle, sheep or pig farming, fish or poultry.

[0004] According to the FAO (Food and Agriculture Organization), insects are considered a sustainable alternative to conventional animal proteins in the face of dwindling natural resources and increasing world population.

[0005] Indeed, insect farming results in low greenhouse gas production compared to cattle or pig farming, with a high rate of protein conversion.

[0006] However, the production and processing of insects into a food product of interest remains difficult and costly. Furthermore, nutritional quality and food safety are important criteria to consider when developing a manufacturing process for a food product on an industrial scale.

[0007] It is in this context that the inventors have demonstrated a continuous process for preparing insect pulp, the continuous process enabling the efficient industrialization of the transformation of insects into a pulp with a low microbial load and preserved nutritional quality, particularly in terms of protein profile. Efficient industrialization means low-cost, high-yield industrialization.

[0008] Thus, the present invention relates to a process for preparing insect pulp from insects comprising the following steps: - grinding the insects, - cooling to a temperature less than or equal to 4°C, said cooling step comprising a dilution-cooling substep by adding water at a temperature between 4°C and 15°C, in which the grinding and cooling steps are carried out continuously.

[0009] The term “pulp” means a product comprising solid particles in a liquid.

[0010] The term "insects" means insects at any stage of development, such as an adult, larval or pupal stage. Preferably, the insects are in the larval stage.

[0011] More particularly, the insects can be chosen from the group consisting of Coleoptera, Diptera, Lepidoptera, Isoptera, Orthoptera, Hymenoptera, Blattoptera, Hemyptera, Heteroptera, Ephemeroptera and Mecoptera, preferably from Coleoptera, Diptera, Orthoptera and Lepidoptera.

[0012] Preferably, the insects are chosen from the group consisting of Tenebrio molitor, Hermetia illucens, Galleria mellonella, Alphitobius diaperinus, Zophobas morio, Blattera fusca, Tribolium castaneum, Rhynchophorus ferrugineus, Musca domestica, Chrysomya megacephala, Locusta migratoria, Schistocerca gregaria, Acheta domesticus and Samia ricini.

[0013] More preferably, the insects are beetles. The beetles preferentially used belong to the families Tenebrionidae, Melolonthidae, Dermestidae, Coccinellidae, Cerambycidae, Carabidae, Buprestidae, Cetoniidae, Dryophthoridae, or mixtures thereof; even more preferably, the insects belong to the family Tenebrionidae.

[0014] More preferably, these are the following beetles: Tenebrio molitor, Alphitobius diaperinus, Zophobas morio, Tenebrio obscurus, Tribolium castaneum and Rhynchophorus ferrugineus, or mixtures thereof, even more preferably Tenebrio molitor and Alphitobius diaperinus.

[0015] Insects are preferably bred and not taken from the wild. For example, insects are bred on an insect farm. Breeding insects on a dedicated farm not only allows for the control and elimination of risks associated with insect-borne diseases, but also limits the risks associated with the toxicity of food products derived from insects, due, for example, to the presence of insecticides. Furthermore, breeding allows for control over the quality of the insect supply and limits procurement costs.

[0016] When applied to a process, "continuous" means a process carried out without interruption in which a continuous flow of material is supplied, as opposed to a discontinuous or batch process.

[0017] The insects are ground using a grinder. Advantageously, the grinder is a wet colloidal grinder. Colloidal grinders are generally used to reduce the size of the elements, particles, that are introduced into them. Colloid grinders consist of two main parts: a fixed part, and a A rotating part (opposite the fixed part). These parts can be smooth or have textured surfaces. The product to be ground is fed into a space located between these two parts, where the grinding takes place.

[0018] The grinding step was successfully carried out with a colloidal type grinder having the characteristics indicated below.

[0019] Advantageously, in the process according to the invention, the grinding is carried out by a colloidal type wet phase grinder, comprising a rotor of generally conical shape having protruding teeth and a stator.

[0020] Indeed, the crusher comprises a rotating part called the rotor. The rotor has a general conical shape, and more specifically, a general outer shell in the shape of a truncated cone. The crusher's rotor has, in particular, four volutes included within this truncated conical shell, which define the rotor's surface. The crusher is configured to drive the rotor in rotation around a central axis. The outer surface of the rotor has protruding teeth. These teeth form sharp helical edges, which describe a portion of a spiral on the surface of the truncated cone formed by the rotor.

[0021] The crusher further comprises a fixed part called the stator. The stator has a general funnel or hopper shape and forms a receiving volume for the rotor. Thus, the receiving volume formed by the rotor corresponds to the general shape of the rotor. A space remains between the stator and the rotor, where the insects are crushed. The stator has teeth, which form sharp edges extending from the base to the top of the stator.

[0022] In the context of the present process, a textured surface of the rotor and / or stator, adapted to cause a cutting action, offers better results for obtaining the desired pulp, because the cuticle of insects, and in particular of larvae, has a certain elasticity which makes it difficult to grind.

[0023] The grinder is fed by a device allowing the insects to be fed at a regular, continuous rate, such as a pneumatic conveying followed by a dosing cyclone or a volumetric or centrifugal pump.

[0024] By cyclone-doser, we mean a device that includes a settling cyclone, which in this case allows air to be evacuated, and a dosing means such as a screw conveyor, located at the bottom of the device, which allows the metering and feeding of the grinder. Such a device is advantageous when the insects are conveyed by a pneumatic conveying system.

[0025] Advantageously, the volumetric or centrifugal pump will have an impeller chosen so as not to damage the insects during feeding, for example, a very open impeller.

[0026] Advantageously, the insects can be introduced via an axial feeding channel that continues into the space between the rotor and the stator. In this space, the insects are reduced to pulp by the action of the edges, which act like knives to cut and reduce the insects, and by the combined action of the rotor and the stator, which create shearing forces in the product.

[0027] Grinders with a similar operating principle can obviously be used in the process. Thus, the grinding step can be carried out without causing the insects to overheat, which could alter the properties of the pulp thus obtained.

[0028] Advantageously, the grinding is carried out in a single step. The residence time in the grinder is preferably less than 30s, more preferably between 15 and 25s, and even more preferably in the order of 10 to 20s.

[0029] The cooling step includes a dilution-cooling substep by adding water at a temperature between 0°C and 15°C. The addition of water both cools the pulp and dilutes it, thus reducing the dry matter content. After the dilution-cooling substep, the insect pulp advantageously has a dry matter content of between 20 and 30% by weight, preferably between 23 and 27% by weight, and even more preferably between 24 and 26% by weight, the percentage by weight being expressed relative to the total weight of the pulp.

[0030] It should be noted that, for the purposes of this application, and unless otherwise stipulated, the ranges of values ​​indicated include the limits. It should also be noted that, for the purposes of this application, the terms "percentage by weight" and "percentages by mass" are equivalent.

[0031] However, the addition of water is insufficient to obtain a pulp at a temperature below 4°C.

[0032] Therefore, in the process according to the invention, the cooling step also includes a sub-step of cooling by heat transfer.

[0033] “Heat transfer cooling” means cooling in which the thermal energy of one fluid is transferred to another fluid without mixing them.

[0034] During the cooling stage, the two sub-stages can be conducted one before the other or simultaneously.

[0035] Advantageously, the device enabling cooling by heat transfer is chosen from a continuous reactor with liquid nitrogen injection, an in-line dynamic mixer with liquid nitrogen injection, heat exchangers or a combination thereof.

[0036] By continuous reactor with liquid nitrogen injection, we mean an industrial equipment comprising a tank whose bottom is fitted with liquid nitrogen injection nozzles, said tank comprising an agitation device.

[0037] By dynamic inline mixer with liquid nitrogen injection, we mean industrial equipment used to continuously mix substances while incorporating liquid nitrogen into the process. It can be used to continuously cool a substance such as a sauce or any other fluid or paste-like substance, and can therefore be referred to as a chiller, or in English, a "sauce chiller".

[0038] Such a dynamic mixer has moving elements, such as blades, which create a mixing motion, a turbulence, in the substance introduced into the mixer. The mixer is said to be "in-line" because it is integrated directly into the production flow, thus allowing continuous mixing of the substance as it passes through it. In practice, the dynamic mixer comprises a cylindrical mixing chamber into which the product to be cooled flows, while a shaft carrying blades, which extends along the main axis of the cylindrical mixing chamber, is driven in rotation, for example by means of a motor.

[0039] Cooling is achieved by injecting liquid nitrogen, for example introduced radially into the mixing chamber. Nitrogen is an inert gas that can be cooled to very low temperatures to become liquid.

[0040] By heat exchangers, we mean more particularly a wide gap plate heat exchanger and / or a tubular type heat exchanger such as a scraped surface heat exchanger.

[0041] Wide-spaced plate heat exchangers and tubular heat exchangers are supplied with refrigerant liquid by devices called chiller units.

[0042] According to a first embodiment of the thermal transfer cooling, the thermal transfer cooling is ensured by a continuous reactor with liquid nitrogen injection and / or an in-line dynamic mixer with liquid nitrogen injection.

[0043] Advantageously, when a continuous reactor with liquid nitrogen injection is used, the dilution-cooling substep is carried out simultaneously with the heat transfer cooling substep since the water is introduced into the reactor simultaneously with the insect pulp.

[0044] When a dynamic in-line mixer with liquid nitrogen injection is used, the dilution-cooling substep is carried out before the heat transfer cooling substep since water is added to insect pulp before it is introduced into the mixer.

[0045] According to a second embodiment of heat transfer cooling, heat transfer cooling is provided by one or more heat exchangers.

[0046] In this embodiment, the water for the dilution-cooling substep is added prior to the introduction of the pulp into the heat exchanger(s). In this embodiment, the dilution substep is therefore carried out before the heat transfer cooling substep.

[0047] Advantageously, the heat transfer cooling is carried out by one or more widely spaced plate heat exchangers and by one or more scraped surface heat exchangers, in that order.

[0048] In this second embodiment of thermal transfer cooling, it is possible, if necessary, to supplement thermal transfer cooling by passing the insect pulp through a continuous reactor with liquid nitrogen injection and / or an in-line dynamic mixer with liquid nitrogen injection.

[0049] At the end of the cooling step, the temperature of the pulp is at a temperature less than or equal to 4°C, preferably between 1 and 4°C.

[0050] According to a first particular embodiment of the process according to the invention, the process for preparing insect pulp from insects comprises the following steps: a) Insect bleaching, b) crushing of insects, c) heating to a temperature of at least 80°C, d) cooling to a temperature less than or equal to 4°C, said cooling step comprising a dilution-cooling substep by adding water at a temperature between 4°C and 15°C, wherein steps a) to d) are carried out continuously.

[0051] The bleaching step washes the insects (removing bits of frass, molts, and substrates adhering to them), lowers the microbial load (reducing the risk of spoilage and ensuring hygiene), and inactivates internal enzymes, thus preventing autolysis and rapid browning of the insects. The bleaching step according to the invention also has the advantage of preserving the integrity of proteins contained in the insects.

[0052] The bleaching step is generally carried out by spraying the insects with water at a temperature between 80 and 98°C, preferably between 85 and 97°C, more preferably between 90 and 97°C, and even more preferably between 92 and 95°C. Preferably, the insects are bleached with water at a temperature of 94 or 95°C.

[0053] The whitening step is carried out in a device called a whitener.

[0054] The term "whiteness" refers to a device that allows the bleaching of insects.

[0055] The residence time of the insects in the whiteness is between 1 and 15 minutes, from Preferably between 3 and 10 minutes.

[0056] For example, the residence time of insects in the whitening solution is 9 minutes when the temperature of the sprayed water is 94°C, or 7 minutes when the temperature of the sprayed water is 95°C. These residence times and temperatures allow for good logarithmic reduction of Clostridium perfringens and Bacillus cereus, which are heat-resistant bacteria.

[0057] Advantageously, the process according to the first particular embodiment includes a scalding step, prior to the blanching step, said scalding step being carried out continuously with steps a) to d).

[0058] The term "scalding step" refers to a step in which the transported insects are immersed in a bath of boiling water. This scalding step makes it possible to cause death as quickly as possible, while respecting animal welfare and in accordance with scientific recommendations. It also allows for an initial washing of the insects.

[0059] By "boiling water," we mean more specifically water with a temperature between 65 and 97°C, preferably between 70 and 90°C, more preferably between 70 and 85°C. Preferably, the boiling step is carried out at a temperature of 75°C.

[0060] Advantageously, the boiling step lasts between 1 and 20 seconds, preferably between 2 and 12 seconds.

[0061] In the process according to the first particular embodiment of the invention, after blanching, the insects are then sent via a transfer and / or feeding system (such as a pneumatic transfer followed by a metering cyclone, a volumetric or centrifugal pump as described above) to the grinding stage. The grinding stage is as described in the general process above.

[0062] After the grinding stage, the pulp obtained undergoes a heating stage.

[0063] The purpose of this heating step is to further reduce the microbial load of the insect pulp.

[0064] During the heating stage, the insect pulp is heated to a temperature of at least 80°C, preferably between 80°C and 130°C.

[0065] According to a first embodiment of the heating step, the insect pulp is sent into a tank heated to a temperature between 80 and 100°C, preferably between 85 and 100°C, more preferably between 90 and 100°C, even more preferably between 92 and 95°C.

[0066] In this embodiment, the residence time of the pulp in the tank during the heating step is between 30 minutes and 4 hours, preferably between 1 hour and 3 hours, even more preferably between 1h30 and 2h30.

[0067] According to a second embodiment of the heating step, the pulp is subjected to in-line sterilization. In-line sterilization can be carried out using a microwave-type device or by direct steam injection (“DSI”, Direct Steam Injection).

[0068] A DSI type device allows instantaneous heat transfer from steam to pulp.

[0069] In this type of device, steam is injected at a temperature of 165°C (6 barg) to 192°C (12 barg), depending on the pressure applied. The residence time of the insect pulp in the DSI device is on the order of 1 to 10 seconds.

[0070] A microwave-type device (or microwave tube) is a continuous industrial microwave heating system, which uses a magnetron to generate microwaves to heat the product passing through the tube.

[0071] In this type of device, the microwave power is from 70 to 400 kW, depending on the flow rate implemented in the continuous process. Preferably, the microwave power is from 75 to 300 kW.

[0072] In this embodiment, the residence time of the pulp in the microwave-type device is between 1 and 10 seconds, preferably 1 to 5 seconds.

[0073] At the outlet of microwave or DSI-type devices, which raise the pulp temperature to 120°C, a chamber is positioned, corresponding to a certain length of piping, in which the pulp is maintained at this temperature (120°C). This piping length corresponds to the residence time required to meet the desired sterilization parameters. It depends not only on the temperature, but also on the flow rate and the type of piping used. For example, to kill 3 log of Clostridium perfringens at 120°C, a residence time of 77 seconds is required; therefore, at a flow rate of 2 liters / hour, 12 meters of DN65 piping will be needed. At a higher temperature, such as 125°C, the residence time is 25 seconds, requiring a length of 4 meters. Alternatively, at 125°C and a flow rate of 6.6t / h, a residence time of 25s and 5m of DN100 piping length are required.

[0074] Advantageously, regardless of the embodiment, the heating step is carried out without the addition of water.

[0075] The cooling step is also as described in the general process above.

[0076] According to a second particular embodiment of the process according to the invention, the process for preparing insect pulp from insects comprises the following steps: i. sterilization of insects, ii. crushing of insects, iii. cooling to a temperature less than or equal to 4°C, said cooling step comprising a dilution-cooling substep by adding water at a temperature between 4°C and 15°C, in which steps i. to iii. are carried out continuously.

[0077] According to this second particular embodiment: - the sterilization step is an in-line sterilization step as described above in the first particular embodiment, which can be carried out using a microwave-type device or by direct steam injection (“DSI”, Direct Steam Injection”); - the grinding and cooling steps being as described in the general process above.

[0078] Advantageously, the process according to the second particular embodiment includes a bleaching step prior to the sterilization step.

[0079] This bleaching step aims to clean the insects and raise their temperature to 80-95°C, such as approximately 90°C. It can be carried out with a bleaching agent according to the methods described above in the first particular embodiment.

[0080] Advantageously, and regardless of the embodiment, in the process according to the invention, after the cooling step, the insect pulp is stored and / or frozen.

[0081] Advantageously, and regardless of the embodiment of the process according to the invention, the latter does not include a pulp fractionation step.

[0082] Advantageously, and regardless of the embodiment of the process according to the invention, the process is also carried out without the addition of a pH adjuster.

[0083] The invention also relates to an insect pulp comprising: - a dry matter content of between 20 and 30% by weight expressed in relation to the total weight of the insect pulp, - a protein content of at least 45% by weight expressed in relation to the dry weight of the pulp, - a lipid content of at least 20% by weight expressed relative to the dry weight of the pulp, and - a microorganism content of less than 1000 CFU / g.

[0084] Preferably, the dry matter content is obtained from the determination of the moisture content according to the method from Regulation EC152 / 2009.

[0085] Advantageously, the pulp according to the invention comprises a dry matter content of between 23 and 27% by weight, the percentage by weight being expressed in relation to the total weight of the pulp.

[0086] Preferably, the pulp comprises a dry matter content of between 24 and 26% by weight, preferably 25% by weight, the percentage by weight being expressed in relation to the total weight of the pulp.

[0087] Throughout the application, where no date is specified for a regulation, standard or directive, it refers to the regulation, standard or directive in force at the filing date.

[0088] Advantageously, the pulp comprises between 45 and 70% by weight of protein, preferably between 49 and 65%, more preferably between 52 and 60%, the percentages by weight being expressed in relation to the dry weight of the pulp.

[0089] In the context of this application, "protein" refers to the quantity of crude protein. The quantification of crude protein is well known to those skilled in the art. Examples include the Dumas method and the Kjeldhal method. Preferably, the Kjeldhal method is used. Unless otherwise specified, "protein" refers not only to proteins but also to peptides and free amino acids.

[0090] Advantageously, the pulp comprises at least 20% essential amino acids, preferably between 20% and 55%, more preferably between 30% and 45% by weight of essential amino acids, the percentages by weight being expressed in relation to the total weight of proteins in the pulp.

[0091] By "total protein weight" or "protein weight" without further indication of the nature of the proteins, we mean the weight of crude proteins present in the pulp. This therefore includes water-soluble and insoluble proteins.

[0092] Preferably, the essential amino acid content is determined according to ISO 13903:2005 (except for tryptophan) and EC Regulation 152 / 2009 (for tryptophan).

[0093] The term “essential amino acid” means the following amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine and arginine.

[0094] Advantageously, the insect pulp comprises a decomposition rate in sensitive amino acids of less than 30%, preferably less than 20%, more preferably less than 10% by weight on the weight of amino acids.

[0095] The term "sensitive amino acids" refers to amino acids that are susceptible to oxidation under the effect of temperature. Sensitive amino acids include arginine, glutamate, leucine, glycine, lysine, methionine, cystine, and cysteine.

[0096] Indeed, as demonstrated in Example 4 (see Table 6), the amino acid content is similar before and after the heating step, including for sensitive amino acids. Therefore, the process according to the invention makes it possible to obtain a pulp with a preserved protein profile.

[0097] It follows that, despite the possible heating step, the proteins in the pulp do not undergo (or hardly undergo) a Maillard reaction.

[0098] Advantageously, the pulp comprises at least 60% by weight of insoluble proteins, preferably between 60 and 90%, even more preferably between 70 and 85%, the percentages by weight being expressed in relation to the total weight of proteins.

[0099] Advantageously, the pulp comprises a content greater than 60%, preferably between 70% and 90%, more preferably between 75% and 85% by weight of water-soluble proteins having a size less than 12400 g / mol, on the total weight of water-soluble proteins.

[0100] By "water-soluble proteins" means, among proteins (or crude proteins), those which are soluble in a solution consisting of 30% acetonitrile, 70% ultrapure water and 0.1% trifluoroacetic acid ("ACN / water / TFA solution"), the percentages being volume percentages out of the total volume of solution, as detailed in Example 4.

[0101] By "insoluble proteins" is meant proteins that are insoluble in the ACN / water / TFA solution, as detailed in Example 4.

[0102] Advantageously, the pulp comprises a content greater than 40%, preferably between 50% and 70%, more preferably between 55% and 60% by weight of water-soluble proteins having a size less than 555 g / mol, on the total weight of water-soluble proteins.

[0103] Preferably, the size of the proteins is determined by HPLC-SEC as detailed in Example 4.

[0104] Advantageously, insect pulp comprises between 20% and 40% by weight of lipids, expressed on the dry weight of the pulp, preferably between 21% and 38% by weight of lipids, more preferably between 25% and 35% by weight of lipids on the dry weight of the pulp.

[0105] The methods for determining fat (lipid) content are well known to those skilled in the art. Preferably, the determination of this content will be carried out following the method of Regulation (EC) No 152 / 2009, as detailed in Example 4.

[0106] Similarly, it is noted that, despite the heating step, the lipids are also preserved (little or no oxidation).

[0107] Advantageously, the pulp has a pepsic and / or ileal digestibility of between 85% and 95%, preferably between 88% and 94%, more preferably between 89% and 93%.

[0108] Preferably, pepsin digestibility is measured according to Directive 72 / 199 / EEC and the ISO 6655 method.

[0109] Ileal digestibility is measured according to the BOISEN method.

[0110] Advantageously, the insect pulp comprises an ash content of less than 10% by weight expressed on the dry weight of the pulp. Preferably, the pulp comprises an ash content of between 0% and 8% by weight, preferably between 0% and 5% by weight on the dry weight of the pulp.

[0111] Preferably, the ash content is determined according to a method of EC Regulation 152 / 2009 as detailed in example 4.

[0112] Advantageously, the insect pulp comprises a fiber content of less than 15% by weight expressed on the dry weight of the pulp. Preferably, the pulp comprises a fiber content of between 2 and 10%, preferably between 3 and 8% by weight of fiber expressed on the dry weight of the pulp.

[0113] Preferably, the fiber content is determined from the crude cellulose content as detailed in example 4.

[0114] The pulp according to the invention has the advantage of having a low microbial load. The bleaching and heating steps detailed above make it possible to significantly reduce the microbial load of the insect pulp.

[0115] The term "low microbial load" means a microorganism content of less than 1000 CFU / g. The term microorganisms refers to bacteria such as mesophilic aerobic flora, mesophilic lactic acid bacteria, E. coli, presumptive Bacillus cereus, Clostridium perfringens, Enterobacteriaceae and / or Salmonella; yeasts and / or molds.

[0116] Advantageously, the insect pulp comprises a content of less than 1000 ufc / g in mesophilic aerobic flora, as determined according to the method NF EN ISO 4833-1.

[0117] Advantageously, the insect pulp comprises a content of less than 1,000 ufc / g in mesophilic lactic acid bacteria, as determined according to method NF ISO 15214.

[0118] Advantageously, the insect pulp comprises a content of less than 100 ufc / g of yeasts and molds, as determined according to method NF V08-059.

[0119] Advantageously, the insect pulp comprises a content of less than 10 ufc / g of E.Coli, as determined according to method NF ISO 16649-2.

[0120] Advantageously, the insect pulp comprises a content of less than 40 ufc / g of Bacillus cereus, as determined according to method BKR 23 / 06-02 / 10.

[0121] Advantageously, the insect pulp comprises a content of less than 10 ufc / g of Clostridium perfringens, as determined according to the method NF EN ISO 7937.

[0122] Advantageously, the insect pulp comprises a content of less than 10 ufc / g in Enterobacteriaceae, as determined according to the method NF EN ISO 21528-2.

[0123] Advantageously, the insect pulp does not contain salmonella-type bacteria as determined according to method BKR 23 / 07-10 / 11.

[0124] As mentioned previously, a pulp is defined as a product comprising solid particles in a liquid.

[0125] Advantageously, the insect pulp comprises particles having a particle size such that 100% of the particles have a size less than 1200 pm (dl00<1200 pm), preferably 100% of the particles have a size less than 1000 pm (dl00<1000 pm).

[0126] Advantageously, and preferably furthermore, the particle size of the insect pulp is such that 90% of the particles have a size less than 900 pm (d90<900 pm), preferably less than or equal to 700 pm (d90=700 pm).

[0127] Particle size analysis refers to the study of the statistical distribution of particle sizes in the pulp. The particle size distribution can be determined by various methods known to those skilled in the art. Laser diffraction is a preferred example.

[0128] Preferably, the insects are as described above for the process. In particular, the insects are beetles and more preferably those described above.

[0129] The invention finally aims at the use of insect pulp according to the invention, for the preparation of animal feed.

[0130] Preferably, the animals are chosen from among domestic animals, grazing animals, poultry or aquatic animals.

[0131] Advantageously, the insect pulp according to the invention is used in the feeding of domestic animals such as dogs, cats, birds, rodents, terrestrial reptiles, and fish. Preferably, the insect pulp is used in dog food.

[0132] Advantageously, the food is in the form of pellets, flakes, pâté, kibble or treats, preferably in the form of pâté.

[0133] The present invention also relates to an insect pulp that can be obtained by a process as described above. DETAILED DESCRIPTION OF THE INVENTION

[0134] Example 1: First method for preparing insect pulp according to the invention

[0135] Live T. molitor larvae are introduced at a rate of 1.9 t / h into a blanching machine that simultaneously boils and bleaches the boiled insects. The larvae are boiled in a hot water bath at 75°C for approximately 9 seconds.

[0136] The scalded larvae then pass through the machine's blanching zone, where they are sprayed with water at 94°C for approximately 15 minutes. These scalding and blanching steps significantly reduce the microbial load (particularly enterobacteria, yeasts, and molds). During their passage through the blanching zone, the larvae absorb approximately 8 to 10% of their weight in water.

[0137] The bleached larvae are then pneumatically transferred at a rate of 2 liters / hour via a transfer system to a metering cyclone, allowing their introduction into a grinder via a "rain" feed. The grinder used is a colloidal wet-phase grinder with a generally conical rotor and a stator. Grinding is carried out in a single step (i.e., in a single pass through the grinder), while still producing an insect pulp with particles having a particle size such that dl00 < 1200 µm, preferably dl00 < 1200 µm, and d90 < 900 µm, preferably d90 = 700 µm. At the grinder outlet, the pulp is at a temperature between 90 and 92°C and has a dry matter content of approximately 31%.

[0138] The pulp is then transferred via a heat-insulated conveyor to a tank for heating. The tank is maintained at 90°C by means of a double jacket into which steam (or alternatively, oil or hot water) is introduced, and the pulp remains in the tank for between 30 minutes and 4 hours. This heat treatment further reduces the microbial load of the pulp.

[0139] Alternatively, the heating step can be carried out by in-line sterilization using a microwave-type device or by direct steam injection (“DSI”, Direct Steam Injection).

[0140] In the case where sterilization is carried out with a microwave-type device, the power required is 75kW for a residence time of 2.5s.

[0141] When sterilization is carried out with a DSI-type device, the steam pressure is between 6 (165°C) and 12 barg (192°C). For a flow rate of 2 liters / hour, the steam consumption is approximately 50 kg / hour and the residence time is approximately 3 seconds.

[0142] At the outlet of the microwave or DSI type devices, which allow the pulp temperature to be raised to 120°C, a chamber is positioned, corresponding to a certain length of piping, in which the pulp is held at This temperature (120°C). This pipe length corresponds to the desired residence time to meet the required sterilization parameters. For example, to kill 3 log of Clostridium perfringens at 120°C, a residence time of 77 seconds is required; therefore, at a flow rate of 2 liters / hour, 12 meters of DN65 pipe will be needed. At a higher temperature, such as 125°C, the residence time is 25 seconds, requiring a length of 4 meters.

[0143] Upon exiting the tank, the pulp, heated to a temperature of 90°C or higher, is sent to a cooling stage. The cooling stage comprises a dilution-cooling substage and a heat transfer cooling substage. For the dilution-cooling stage, water at a temperature of 13°C or lower, preferably 4°C or even 2°C, is added at a rate of 0.5 t / h. Heat transfer cooling is preferably carried out in a continuous reactor with liquid nitrogen injection and / or an inline dynamic mixer with liquid nitrogen injection. When a continuous reactor with liquid nitrogen injection is used, the water is added simultaneously to the pulp in the reactor. When an inline dynamic mixer with liquid nitrogen injection is used, the water is added to the pulp before it enters the mixer.

[0144] At the end of the cooling step, the pulp is at a temperature between 0 and 4°C. Optionally, an antioxidant, such as tocopherol or essential oils of rosemary, can be added to the pulp, for example, in a similar manner to the dilution-cooling water.

[0145] At the end of this cooling step, the pulp has a dry matter content of approximately 25% by weight of the total weight of the pulp.

[0146] The pulp can then be stored at a temperature between 0 and 4°C in tanks before optional freezing at a temperature of -18°C.

[0147] Example 2: _ Second process for preparing insect pulp according to the invention

[0148] Live T. molitor larvae are introduced at a rate of 6 liters / hour into a blanching machine that simultaneously boils and bleaches the boiled insects. The larvae are boiled in a hot water bath at 75°C for 3 seconds.

[0149] Then the scalded larvae pass into the bleaching zone of the machine, in which water at 95 °C is sprayed on them for 6 minutes.

[0150] The bleached larvae are then sent, at a rate of 6.6 t / h, to a grinder. The grinder used is a colloidal wet-phase grinder comprising a generally conical rotor and a stator. Grinding is carried out in a single step (i.e., in a single pass through the grinder), while still producing an insect pulp with particles having a particle size such that dl00<1200pm, preferably dl00<1200pm, and d90<900pm, preferably d90=700pm. At the outlet of the crusher, the pulp is at a temperature between 90-92°C and has a dry matter content of around 31%.

[0151] The pulp is then transferred via a heat-insulated conveyor to a tank for a heating step. The tank is maintained at 90°C by means of a double jacket into which steam (or alternatively, oil or hot water) is introduced, and the pulp remains in the tank for between 30 minutes and 4 hours. This heat treatment further reduces the microbial load of the pulp.

[0152] Alternatively, as in Example 1, the heating step can be carried out by in-line sterilization using a microwave-type device or by direct steam injection (“DSI”, Direct Steam Injection).

[0153] In the case where sterilization is carried out with a microwave-type device, the power required is 150kW for a residence time of 2.5s.

[0154] When sterilization is carried out with a DSI type device, the steam pressure is between 6 and 12 barg. For a flow rate of 6.6 t / h, the steam consumption is on the order of 150 kg / h and the residence time is approximately 1 s.

[0155] At the outlet of microwave or DSI-type devices, which raise the pulp temperature to 125°C, a chamber is positioned, corresponding to a certain length of piping, in which the pulp is maintained at this temperature (125°C). This piping length corresponds to the desired residence time to meet the required sterilization parameters. For example, to kill 3 log of Clostridium perfringens at 125°C, a residence time of 25 seconds is required; therefore, at a flow rate of 6.6 t / h, 5 m of DN100 piping will be necessary.

[0156] Upon exiting this tank, the pulp, heated to a temperature of 90°C or higher, is sent to a cooling stage. The cooling stage comprises a dilution-cooling substage and a heat transfer cooling substage. In this embodiment, the dilution-cooling substage is carried out by adding water to the insect pulp using a static mixer. The water, at a temperature of 13°C or lower, preferably 4°C or even 2°C, is added at a rate of 1.6 t / h. The insect pulp, at a rate of 8.2 t / h, is then cooled by heat transfer using heat exchangers. The heat exchangers are advantageously scraped-surface heat exchangers arranged in series, possibly preceded by one or more plate heat exchangers.Optionally, a continuous reactor with liquid nitrogen injection or an in-line dynamic mixer with liquid nitrogen injection can also be added at the end of the cooling stage. At the end of the cooling stage, the pulp is at a temperature of between 0 and 4°C. Optionally, an antioxidant, such as tocopherol or rosemary essential oils, can be added to the pulp, for example, at the outlet of the heat exchangers.

[0157] At the end of this cooling step, the insect pulp has a dry matter content of approximately 25% by weight of the total weight of the insect pulp.

[0158] The insect pulp can then be stored at a temperature between 0 and 4°C in tanks before optional freezing at a temperature of -18°C.

[0159] Example 3: Third process for preparing insect pulp according to the invention

[0160] Live T. molitor larvae are introduced at a rate of 6.lt / h into a bleaching chamber in order to wash and heat them to a temperature of around 90°C.

[0161] They are then sterilized in-line using a microwave-type device or by direct steam injection (“DSI”, “Direct Steam Injection”) at a rate of 6.4t / h.

[0162] In the case where sterilization is carried out with a microwave type device, the power required is 300kW for a residence time of 2.5s.

[0163] When sterilization is carried out with a DSI type device, the steam pressure is between 6 and 12 barg. For a flow rate of 6.4 t / h, the steam consumption is on the order of 300 kg / h and the residence time is approximately 1.7 s.

[0164] At the outlet of microwave or DSI-type devices, which raise the pulp temperature to 125°C, a chamber is positioned, corresponding to a certain length of piping, in which the pulp is maintained at this temperature. This piping length corresponds to the desired residence time to meet the required sterilization parameters. For example, to kill 3 log of Clostridium perfringens at 125°C, a residence time of 25 seconds is required; therefore, at a flow rate of 6.4 t / h, 5 m of DN100 piping will be necessary.

[0165] The sterilized larvae are then conveyed at a rate of 6.4 t / h, via a transfer system such as a volumetric pump, to a grinder. The grinder used is a colloidal wet-phase grinder with a generally conical rotor and a stator. Grinding is carried out in a single step (i.e., in a single pass through the grinder), while still producing an insect pulp with particles having a particle size such that dl00 < 1200 µm, preferably dl00 < 1200 µm, and d90 < 900 µm, preferably d90 = 700 µm. At the grinder outlet, the pulp is at a temperature of approximately 99–100°C and has a dry matter content of approximately 31%.

[0166] At the outlet of the crusher, the pulp is sent to a cooling stage. The cooling stage comprises a dilution-cooling substage as well as a heat transfer cooling substage. In this embodiment, the dilution-cooling substep is carried out by adding water to the insect pulp using a static mixer. The water, at a temperature of 13°C or lower, preferably 4°C or even 2°C, is added at a rate of 1.6 t / h. The insect pulp, at a rate of 8 l / h, is then cooled by heat transfer using heat exchangers. The heat exchangers are advantageously scraped-surface heat exchangers arranged in series, optionally preceded by one or more plate heat exchangers. Optionally, a continuous reactor with liquid nitrogen injection or an in-line dynamic mixer with liquid nitrogen injection can also be added at the end of the cooling step. At the end of the cooling step, the pulp is at a temperature between 0 and 4°C.Optionally, an antioxidant, such as tocopherol or rosemary essential oils, can be added to the pulp, for example, at the outlet of the heat exchangers.

[0167] At the end of this cooling step, the insect pulp has a dry matter content of approximately 25% by weight of the total weight of the insect pulp.

[0168] The insect pulp can then be stored at a temperature between 0 and 4°C in tanks before optional freezing at a temperature of -18°C.

[0169] Example 4: Characterization of insect pulp according to the invention

[0170] The pulp obtained in Example 1 was characterized as follows.

[0171] L Analyses

[0172] L1 Determination of dry matter content The dry matter content was calculated from the moisture content, determined according to the method from EC Regulation 152 / 09.

[0173] L2 Determination of the quantity of protein The protein content was determined according to the Kjeldahl method, of EC regulation 152 / 2009, with a protein conversion factor N of 6.25.

[0174] 1.3 Determination of the quantity of lipids The quantity of lipids was determined according to EC Regulation 152 / 2009.

[0175] 1.4 Determination of the quantity of ash The ash content was determined according to EC Regulation 152 / 2009.

[0176] 1.5 Determination of the quantity of fibers The fiber content was determined from the crude cellulose content determined by gravimetry using a Fibersac® device.

[0177] 1.6 Determination of the quantity of amino acids The quantity of total amino acids was determined according to ISO 13903:2005 and EC Regulation 152 / 2009 (for tryptophan).

[0178] 1.7 Determination of pepsin digestibility Pepsin digestibility was determined according to Directive 72 / 199 / EEC and ISO method 6655

[0179] 1.8 Determination of ileal digestibility Ileal digestibility was determined according to the BOISEN methods (for enzyme assay) and according to the Dumas method (for protein content).

[0180] 1.9 Determination of the quantity of soluble and insoluble proteins The quantity of soluble proteins was determined by solubilizing said proteins in a solution consisting of 30% acetonitrile, 70% ultrapure water and 0.1% trifluoroacetic acid (“ACN / water / TFA solution”), these percentages being volume percentages of the total volume of solution, which constitutes the mobile phase before assay by HPLC-SEC (size exclusion chromatography method known to those skilled in the art). The amount of insoluble protein was determined by the dry residue obtained after dissolving a sample of dried pulp in the ACN / water / TFA solution, and reported to the initial dry weight.

[0181] 1.10 Protein Size Determination Protein size was determined by HPLC-SEC.

[0182] 1.11 Determination of the quantity of minerals The content of each of the minerals listed in Table 8 below was determined by ICP / AES (inductively coupled plasma atomic emission spectrometry).

[0183] 1.12 Determination of the quantity of heavy metals and mycotoxins

[0184] The heavy metal content was determined by ICP-MS (Inductively Coupled Plasma Mass Spectrometry) after microwave mineralization.

[0185] The mycotoxin content was determined for zearalenone and T2 / HT-2 toxins by extraction, purification and analysis by LC MS / MS (liquid chromatography coupled to mass spectrometry), and for aflatoxins and ochratoxin by HPLC-Fluorimetry (high-performance liquid chromatography coupled to a fluorescence detector).

[0186] 2. Results

[0187] [Tables 1] Pulp Units Dry Matter % by weight of pulp 26.86* Protein g / 100 g of pulp by dry weight 53.87* Fat 29.67** Ash 4.15*** Fiber g 9**** Average results calculated on 8 pulps

[0188] **Average results calculated on 7 pulps

[0189] ***Average results calculated on 7 pulps

[0190] ****Average results calculated on 2 pulps

[0191] Table 1: Pulp composition

[0192] [Tables2] Amino Acids Unit Pulp* Alanine g / 100g of pulp (dry weight) 3.81 Arginine 2.65 Aspartic acid 4.17 Cysteine ​​+ Cystine 0.43 Glutamic acid 5.66 Glycine 2.68 Histidine 1.56 Isoleucine 2.11 Leucine 3.71 Lysine 2.89 Methionine 0.66 Phenylalanine 1.83 Proline 4.05 Serine 2.33 Threonine 2.09 Tryptophan 0.64 Tyrosine 3.64 Valine 3.14 Methionine + Cysteine ​​1.09 Phenylalanine + Tyrosine 5.47

[0193] *average results calculated on 3 pulps

[0194] Table 2: Amino acid content in the pulp

[0195] [Tables3] % by mass expressed relative to total protein % of proteins with a size >12.4 kDa 4.5% of proteins with a size between 12.4 and 6.5 kDa 4.4% of proteins with a size between 6.5 and 1.4 kDa 0.7% of proteins with a size between 1.4 and 0.555 kDa 0.7% of proteins with a size < 0.5 55 13.1% of insoluble proteins 81.3% by mass expressed relative to the protein fraction of wheat proteins % of proteins with a size >12.4 kDa 19.3% of proteins with a size between 12.4 and 6.5 kDa 18.9% of proteins with a size between 6.5 and 1.4 kDa 3.1% of proteins with a size between 1.4 and 0.555 kDa 2.8% of proteins with a size < 0.5 55 55.8

[0196] Table 3: Protein Size

[0197] [Tables4] Digestibility Unit Pulp Pepsic digestibility % 89.8 Ileal digestibility % 92.3

[0198] Table 4: Digestibility

[0199] [Tables5] 90°C 0 min % protein by wet weight of 1 a pulp 14.6 Standard error in protein content. Pepsic digestibility 91.3. Standard error in pepsic digestibility 3.8. 10 min. % protein on wet weight of 1 a pulp 14.5. Standard error in protein content 0.4. Pepsic digestibility 92.1. Standard error in pepsic digestibility 3.8. 30 min. % protein on wet weight of 1 a pulp 14.6. Standard error in protein content 0.4. Pepsic digestibility 91.9. Standard error in pepsic digestibility 88.5. 60 min % protein on wet weight of 1 a pulp 14.7 Standard error protein content 0.4 Pepsic digestibility 90.4 Standard error pescic digestibility 3.8

[0200]

[0201] Table 5: Measurement of pepsin digestibility and protein content before and after heating to 90°C [Tables] 0 min Std 30 min Std 2H Std 3H Std Tryptophane t otal 0,180 0,019 0,181 0,019 0,178 0,02 0,179 0,021 Thréonine 0,554 0,081 0,584 0,086 0,553 0,086 0,546 0,088 Acide aspartiq ue 1,140 0,167 1,188 0,175 1,137 0,176 1,125 0,182 Sérine 0,656 0,096 0,673 0,099 0,655 0,102 0,626 0,101 Lysine 0,787 0,115 0,804 0,118 0,763 0,118 0,766 0,124 Valine 0,893 0,13 0,933 0,137 0,880 0,137 0,874 0,141 Proline 1,111 0,162 1,141 0,168 1,146 0,178 1,081 0,175 Alanine 1,130 0,165 1,179 0,174 1,128 0,175 1,090 0,176 Phénylalanine 0,521 0,076 0,518 0,076 0,510 0,079 0,496 0,08 Isoleucine 0,603 0,088 0,619 0,091 0,602 0,093 0,585 0,095 Glycine 0,769 0,112 0,793 0,117 0,765 0,119 0,745 0,121 Tyrosine 0,987 0,144 1,046 0,154 1,011 0,157 0,969 0,157 Arginine 0,740 0,108 0,749 0,11 0,730 0,113 0,711 0,115 Leucine 1,034 0,151 1,084 0,16 1,020 0,158 1,012 0,164 Histidine 0.438 0.064 0.454 0.067 0.419 0.065 0.418 0.068 Glutamic acid 1.552 0.227 1.587 0.234 1.516 0.235 1.522 0.246 Methionine 0.192 0.028 0.191 0.028 0.171 0.027 0.177 0.029 Cysteine ​​+ Cystine 0.116 0.017 0.106 0.016 0.107 0.017 0.097 0.016

[0202] Table 6: Amino acid content in g per 100g at 25% dry matter, before heating (0 min) and after heating at 90°C for 30 min, 2H or 3H.

[0203] Tables 5 and 6 show that the quality of the pulp proteins is not degraded by the heating step.

[0204] Indeed, it is observed that the digestibility of the proteins is similar at T=0 (i.e., without heating the pulp) and at T=60 min, taking into account the standard error. Digestibility is a good indicator of protein quality. In fact, the more denatured the proteins, the less digestible they are.

[0205] In addition, the amino acid profile of the pulp is not modified by the heating step, and this also applies to the most sensitive amino acids, namely lysine, methionine and cysteine.

[0206] The process according to the invention therefore makes it possible to obtain a pulp whose amino acid profile is not altered and avoids the degradation of proteins.

[0207] [Tables?] Minerals Units Pulp Sodium (Na) mg / kg of pulp by dry weight 1396.08 Potassium (K) 9098.04 Calcium (Ca) 533.33 Phosphorus (P) 7490.20 Magnesium (Mg) 2513.73 Iron (Fe) 53.73 Copper (Cu) 17.73 Manganese (Mn) 10.67

[0208] Table 7: Minerals

[0209] [Tables8] Fatty acids Units Pulp C12:0 (lauric acid) % by mass expressed per ra 0.22 C14:0 (myristic acid) 2.93 C16:0 (palmitic acid) as a percentage of total lipids 15.87 Cl8:0 (stearic acid) 2.84 C18:1-n9c (oleic acid) 44.76 C18:2-n6c (linoleic acid) 28.26 C18:3-n3 (alpha-linolenic acid) 1.39 Saturated fatty acids (SFA) 22.31 Monounsaturated fatty acids (MUFA) 47.48 Polyunsaturated fatty acids (PUFA) 29.85 PUFA / SFA Ratio 0.63 Trans fatty acids % by mass expressed as a percentage of total lipids 0.27 Total omega-3 fatty acids 1.44 Total omega-6 fatty acids 28.26 Ratio of total omega-6 fatty acids to total omega-6 fatty acids Mega 3 Ratio 19.6

[0210] Table 8: Fatty acid content in the pulp

[0211] [Tables 9] Heavy Metals and Mycotoxins Unit Pulp Arsenic mg / kg <0.05 Cadmium 0.02 Mercury <0.005 Lead <0.01 Aflatoxin B1 Pg / kg <0.1 Aflatoxin B2 <0.1 Aflatoxin G1 <0.1 Aflatoxin G2 <0.2 Total Aflatoxins <0.20 Ochratoxin A <0.2 Zearaleone <20 HT-2 Toxin <20 T-2 Toxin <20

[0212] Table 9: Heavy metal and mycotoxin content in the pulp

[0213] [TableauxlO] Parameters Method Results Mesophilic aerobic flora (30°C) CFU / g NF EN ISO 4833-1 < 1,000 Mesophilic lactic acid bacteria (30°C) CFU / g NF ISO 15214 < 1,000 Yeasts and molds CFU / g NF V08-059 < 100 Escherichia coli [3-glucuronide positive] CFU / g NF ISO 16649-2 < 10 Presumptive Bacillus cereus (30°C) CFU / g BKR 23 / 06 - 02 / 10 < 40 Clostridium perfringens CFU / g NF EN ISO 7937 < 10 Enterobacteriaceae (37°C) CFU / g NF EN ISO 21528-2 < 10 Salmonella / 25 g BKR 23 / 07-10 / 11 Not detected

[0214] Table 10: Results of microbiological analysis of the pulp

Claims

Demands

1. A process for preparing insect pulp from insects comprising the following steps: - grinding the insects, - cooling to a temperature less than or equal to 4°C, said cooling step comprising a dilution-cooling substep by adding water at a temperature between 4°C and 15°C, wherein the grinding and cooling steps are carried out continuously.

2. A method according to claim 1, wherein the grinding is carried out by a colloidal wet-phase mill, comprising a generally conical rotor with protruding teeth and a stator.

3. A method according to claim 1 or 2, wherein the cooling step also includes a substep of cooling by heat transfer.

4. A process for preparing insect pulp from insects according to any one of claims 1 to 3, comprising the following steps: a. bleaching the insects, b. grinding the insects, c. heating to a temperature of at least 80°C, d. cooling to a temperature less than or equal to 4°C, said cooling step comprising a substep of dilution-cooling by adding water at a temperature between 4°C and 15°C, wherein steps a) to d) are carried out continuously.

5. A process according to claim 4, comprising a scalding step prior to the blanching step, said scalding step being carried out continuously with steps a) to d).

6. A method for preparing insect pulp from insects according to any one of claims 1 to 3, comprising the following steps: i. sterilization of the insects, ii. crushing of insects, iii. cooling to a temperature less than or equal to 4°C, said cooling step comprising a dilution-cooling substep by adding water at a temperature between 4°C and 15°C,

7.

8. in which steps i. to iii. are carried out continuously. A process according to claim 6, comprising a bleaching step prior to the sterilization step. A process according to any one of claims 1 to 7, wherein the insect pulp is stored and / or frozen.