METHOD FOR KILLING AND PRESERVING INSECT LARVAE AND / OR INSECTS, INSECTS, LARVAE, METHOD FOR MANUFACTURING FOOD AND ASSOCIATED FOOD

Abstract

The present invention relates to a method for killing and preserving larvae and / or insects arranged to form a volume of larvae and / or insects. Characteristically, said volume of insect larvae is subjected to steam for a duration t1 sufficient for the temperature inside said volume, and in particular at the center of said volume, to reach a value equal to or greater than 50°C, and in particular equal to 60°C, 70°C, 80°C, 90°C or 95°C. The killed larvae and / or insects are then flash-frozen, optionally after being cooled to a given temperature, and the killed and frozen larvae and / or insects are stored at a negative temperature. The present invention also relates to an insect larva and / or a slaughtered and preserved insect, a method for manufacturing a food using such larvae and / or insects, and a food obtained by the method.

Description

Title of the invention: METHOD FOR KILLING AND PRESERVING INSECT LARVAE AND / OR INSECTS, INSECTS, LARVAE, METHOD FOR MANUFACTURING FOOD AND ASSOCIATED FOOD Technical field

[0001] The present invention relates to a method for slaughtering and preserving insect larvae or insects which can be implemented on an industrial basis, a larva and / or insect slaughtered by this method, a method for manufacturing food using this larva and / or insect and food obtained from said larva and / or insect. Previous Art

[0002] For some years now, the use of insects and their larvae has been considered as a source of animal protein for animal and human consumption. Insect farming has a much smaller ecological impact than raising mammals or even chickens. Furthermore, entomophagy is widespread in certain cultures of Latin America, Africa, and Asia.

[0003] The document entitled “Quality Aspects of Insects as Food—Nutritional, Sensory, and Related Concepts by Elhassan et al., published in the journal Foods on March 12, 2019, indicates that mealworm larvae can be cooked in various ways for immediate consumption. According to this document, mealworm larvae can be eaten after being steamed, boiled, or roasted. This method of cooking the larvae also kills them.

[0004] The document entitled “Effect of blanching followed by refrigerated storage or industrial microwave drying on the microbial load of yellow mealworm larvae” by D. Vandeweyer, published in 2017 in the journal Food Control (pages 311-314), discloses a technique for killing mealworm larvae in which the larvae are immersed in boiling water for 10, 20, or 40 seconds. The larvae are then cooled in ice water and vacuum-sealed before being stored in a refrigerator at 3°C. The larvae can also be microwave-dried after blanching in boiling water. This document indicates that these techniques reduce the bacterial load but are not sufficient to destroy endospores.

[0005] On an industrial scale, insects or their larvae must be killed and then preserved in order to be used subsequently in manufacturing processes food preparations. Most of the time, the insects or their larvae are dried and then ground into powder, forming a protein flour that is easy to use and microbiologically stable.

[0006] However, flour cannot be used as such in the manufacture of all foods, particularly in the manufacture of wet foods, such as pâté.

[0007] Furthermore, blanching larvae by soaking them in boiling water does not allow for the reproducible killing of a large number of larvae. Indeed, the larvae swell with water, which reduces the volume of water used for blanching. It is therefore necessary to replenish the volume of water used for blanching each time and then reheat it. Moreover, while reusing water already used for blanching saves time and water, it is not hygienic. Since the larvae are washed by the blanching water, they contaminate it, which then becomes concentrated with bacteria, mycobacteria, and spores, which are not necessarily destroyed by heat.

[0008] Furthermore, the document entitled “Effect of different blanching treatments on microbiology, al profile and quality of the mealworm” by Mancini et al., published in the Journal of Insects as Food and Feed in 2019 (pages 225 to 234), indicates that it is desirable to avoid browning of mealworm larvae after slaughter. Blanching at 60°C for 5 minutes kills the larvae and prevents browning. Indeed, browning reduces protein digestibility and alters the flavor of the larvae; it should therefore be avoided in slaughtered larvae.

[0009] One object of the present invention is to propose a method for killing and preserving an insect larva and / or an insect that can be easily implemented on an industrial scale.

[0010] Another object of the present invention is to propose a method of slaughtering and preserving an insect larva which avoids the browning of the slaughtered larva.

[0011] Another object of the present invention is to propose a method of slaughtering and preserving an insect larva and / or an insect which makes it possible to preserve the larva and / or the insect slaughtered by freezing / deep freezing without reducing it to powder and without drying it.

[0012] Another object of the present invention is to provide a method for slaughtering and preserving an insect larva and / or an insect, which can then be used for the manufacture of a food preparation, in particular a wet food preparation whose texture, smell and color are easy to control to be in accordance with the wishes and tastes of consumers.

[0013] The present invention relates to a method for killing and preserving insect larvae and / or insects which are arranged to form a volume, according to which, characteristically, said volume of insect larvae and / or insects is subjected to steam for a period of time sufficient for the temperature inside said volume and in particular at the center of said volume to reach a value equal to or greater than 50°C and in particular equal to 60°C, 70°C, 80°C, 90°C or 95°C, said larvae and / or said slaughtered insects are flash-frozen / deep-frozen, possibly after cooling to a given temperature and said larvae and / or said slaughtered and frozen / deep-frozen insects are stored at a negative temperature.

[0014] The term "volume of larvae and / or insects" is not limited according to the invention. The term volume refers to a collection of larvae and / or insects deposited on a support (conveyor belt or other) and a collection of larvae and / or insects deposited in a container with edges, the volume being delimited by the edges of the container.

[0015] The water vapor is advantageously water vapor at 100°C and atmospheric pressure. The pressure is nevertheless not limited to atmospheric pressure.

[0016] The total duration of the steam treatment is not limited according to the invention. Thus, if the duration tl allows a stable temperature of 50°C to be reached, the duration of the steam treatment is sufficient to kill the larvae. It can be determined experimentally based on the volume of larvae treated. If the temperature reached at the end of the duration tl is around 70°C, 80°C, 90°C, or 95°C, the treatment duration can be equal to tl because the larvae died during the time required to reach the core temperature at tl, the lethal temperature for larvae being 50°C.

[0017] The use of steam allows for a reproducible and simple process to implement, unlike bleaching by immersion in hot water. The process of the invention is similar to a bleaching process.

[0018] The larvae and / or insects can be frozen at -20°C by mechanical refrigeration and then stored at -18°C like a frozen fresh food. They can also be frozen at -30°C by cryogenic refrigeration and then stored at -18°C. In all cases, they can be stored at -20°C or -18°C.

[0019] In a particular embodiment, the process is implemented only on insect larvae.

[0020] Advantageously, the temperature at the center of said volume is maintained at a value greater than 50°C and in particular equal to 60°C, 70°C, 80°C, 90°C or 95°C for a duration t2 such that the total duration of the steam treatment step is greater than or equal to 6min, 7min, 8min, 9min, 10min, 11min and less than or equal to 20min.

[0021] Indeed, the Applicant found that, surprisingly, the duration of the steam blanching step affected certain characteristics of a product obtained by cooking larvae and / or insects slaughtered and preserved according to the process of the invention.

[0022] If the blanching time is too short, a grey film appears on the surface of the cooked product and / or a rapid change in color to a greyish or greenish hue is observed, which puts the consumer off. While the Applicant is not bound by such an explanation, it would appear that the longer the blanching time, the more enzymatic reactions are deactivated. Since the larva and the insect are whole organisms, numerous enzymatic reactions are likely to occur, unlike in meat, which is only a piece of muscle.

[0023] The larva and / or insect to be killed is not limited according to the invention. It may be the larva of the black soldier fly (Hernie lia Illucenssp), the larva of the housefly (Musca domestica), the larva of the mealworm (Tenebrio molitor), the larva of the lesser mealworm (Alphitobius diaperinus), the larva of the house cricket (Acheta domesticus), the larva of the tropical house cricket (Gryllodes sigdlalussp), the larva of the steppe cricket (Gryllus assimilis), and mixtures of these larvae, or the aforementioned insects, alone or in mixture, and possibly in mixture with larvae of the same insect or of one or more different insects chosen from those mentioned above.

[0024] According to a particular implementation method, said volume of larvae and / or insects treated may, for example, be substantially equal to or greater than 4000 cm3 and less than or equal to 5000 cm3.

[0025] The process of the invention can be carried out in a steam tunnel, with the larvae and / or insects placed on a conveyor belt, or in a steam oven. In the latter case, the larvae and / or insects are preferably placed in a thermally conductive container. The process is thus easy to implement. The larvae and / or insects contained in their container are then simply frozen at -20°C, particularly after cooling to a temperature of 10°C or lower, for example.

[0026] Advantageously, regardless of the method of implementation of the process of the invention, the duration of the steam treatment step is such that the water absorption by mass of the larvae after steam treatment is less than or equal to 20%, in particular less than or equal to 15% and equal to or greater than 7%. This water absorption is sufficient to subsequently obtain good freezing of the larvae without alteration.

[0027] Advantageously, the duration of the steam treatment step and the temperature of the freezing / deep-freezing step are such that the water intake of the slaughtered and frozen / deep-frozen larva is substantially equal to or greater than 3%, in particular substantially equal to 5% and substantially equal to or less than 9% and in particular substantially equal to 7%.

[0028] The present invention also relates to a larva and / or an insect that can be obtained according to the process of the invention. Advantageously, the present invention This relates to an insect larva that can be obtained according to the process of the invention. Typically, the slaughtered and frozen larva and / or insect of the invention has a density equal to or greater than 295 and equal to or less than 325 and / or a water activity equal to or greater than 0.960 and equal to or less than 0.981 and / or an energy value less than or equal to 210 kcal / 100g and / or a carbohydrate content greater than or equal to 4.0 g / 100g and / or a lipid content less than or equal to 10 g / 100g and / or a protein content equal to or less than 22 g / 100g. The aforementioned values ​​can be obtained, in particular, after 78 days of storage at -18°C / -20°C.

[0029] According to a particularly advantageous embodiment, the felled and frozen larva and / or insect has a density equal to or greater than 295 and equal to or less than 325 and a water activity equal to or greater than 0.960 and equal to or less than 0.981.

[0030] The present invention relates more particularly to frozen / deep-frozen larvae as described above. They may be in the form of a compact block or separated from one another. The larvae and / or insects may also be in the form of pieces or a puree.

[0031] The Applicant has observed that the larvae and / or insects slaughtered and stored according to the process of the invention exhibited lower water activity than larvae obtained by water bleaching. They are therefore more stable from a microbiological point of view.

[0032] Furthermore, since larvae and / or insects slaughtered and preserved according to the process of the invention contain more water than larvae slaughtered by other methods, they are easier to use for preparing a wet food such as pâté, which may be intended for animal or human consumption. The water content facilitates the production of a wet food and allows for easy adjustment of the texture, particularly in the case of a wet food, such as pâté.

[0033] The present invention also relates to a method of manufacturing a food according to which, characteristically, frozen larvae and / or insects according to the invention are reduced to pieces and said pieces are mixed with a food composition which contains a flour of at least one cereal and / or at least one fruit and / or at least one vegetable, in particular at least one frozen fruit and / or at least one vegetable(s) and said mixture is cooked.

[0034] All ingredients can be mixed frozen in such a way as to reduce bacterial growth and warming of the material.

[0035] The larvae and / or insects of the invention can therefore be used for the manufacture of kibble by high-temperature extrusion or for the manufacture of kibble by extrusion at 90°C low pressure, in particular with a Wenger TT3630 extruder.

[0036] The larvae and / or insects of the invention can also be used to manufacture a moist food such as pâté, mousse, minced meat, or meatballs in sauce, for example. The moist food can be obtained by canning and / or sterilized during cooking.

[0037] The manufacturing process for a food according to the invention therefore relates to any cooked food, of the type croquette or of the type pâté, pâté, mousse, minces or balls in sauce, in particular.

[0038] In particular, with regard to food intended for a pet (dog or cat), the food according to the invention has the advantage of being hypoallergenic because it can contain only one source of animal protein. Since this source is an insect larva that has not, or rarely, been ingested by the animal, the food of the invention has a low risk of causing an allergic reaction. Furthermore, the use of a cereal such as sorghum, which is rarely used in animal and even human food in Europe, Asia, and North America, reinforces the hypoallergenic nature of the food of the invention.

[0039] The present invention also relates to a food containing larvae and / or insects according to the invention and / or at least one fruit and / or at least one vegetable and / or at least one cereal. This food may be a pâté, cat or dog food, or kibble, a mousse, balls in gravy, minced food, or any other type of food intended for pets or other carnivorous or omnivorous animals (in particular animals known as exotic pets, for example, chickens, birds, reptiles), which may possibly include humans.

[0040] The food, particularly when intended for human consumption, may also include other sources of animal protein such as, for example, pork, rabbit, chicken, hen, fish, game and / or offal.

[0041] The fruit is not limited according to the invention. It can be chosen from apples, pears, berries such as blueberries, grapes, bananas, apricots, peaches, strawberries, watermelons, or melons. The fruit is chosen according to the animal for which the food is intended.

[0042] The present invention also relates to a flour obtained from the larvae and / or insects of the invention.

[0043] The vegetable is not limited according to the invention. It can be chosen from among potatoes, carrots, spinach, salad greens (in particular lettuce), cabbage, celery, green beans, peas, squash, zucchini, pumpkin, and cucumber, for example. The vegetable is chosen according to the animal for which the feed is intended.

[0044] The cereal is not limited according to the invention. It can be chosen from rice, millet, wheat, barley, oats, grasses such as sorghum, buckwheat, and herbaceous plants such as amaranth.

[0045] The food of the invention and the food composition used in the process of manufacturing a food according to the invention may also include a legume such as lentils, chickpeas, split peas, or dried white or red beans. The food may also include an aerial fungus such as button mushrooms or oyster mushrooms, for example.

[0046] For the purposes of the present invention, the term "pâté" refers to a preparation containing animal protein and a vegetable. The pâté is intended for human consumption. The term encompasses both pâtés en croûte and baked terrines.

[0047] For the purposes of the present invention, the term "pâté" refers to a pâté-type food as described above but intended for animal feeding, in particular for cats and dogs.

[0048] The present invention, its features and the various advantages it provides will become clearer upon reading the following examples, which are given by way of non-limiting example and which refer to the accompanying drawings in which:

[0049] - Fig. 1 shows a photograph of a can of cat food obtained with larvae killed by flash freezing; and

[0050] - Figure 2 shows a photograph of a can of cat food obtained with larvae killed by the process of the invention. EXAMPLES

[0051] The larvae used are mealworm larvae.

[0052] 1) Comparison of cold slaughter and slaughter by blanching immersion in water and slaughter by steam.

[0053] The following table 1 groups together the methods of killing darkling beetle larvae whose temperature is 20°C before killing.

[0054] [Tables 1] Cryogenic Method: Mechanical cooling, steam oven, bleaching, immersion in water. Ambient temperature: -60°C to -30°C. Water vapor at 100°C. Water at 100°C. Core temperature: -24°C to -24°C. a) 95°C b) < 50°C c) 95°C d) 95°C. No probe. Time 3h approx More than 5h a) More than 25 min b) 2 min 40 c) 5 min d) 10 min 2 min

[0055]

[0056] It is observed that the methods using heat are faster. The larvae killed after 25 min of contact with steam were swollen with water.

[0057] The Applicant observed that the temperature rise time is variable and depends on the density of the larvae. Furthermore, it was observed that the larvae cluster in the center of the container to avoid the heat. The larvae therefore have a density that is not homogeneous, either spatially or temporally. Heat transfer is thus difficult to model since it depends on the empty spaces between the larvae, their composition and size, and their movements.

[0058] When the contact time with the steam is 2 minutes and 40 seconds, it is not possible to reach a temperature high enough to kill the larvae at the center of the volume. The lethal temperature for the larvae is 50°C. When the contact time with the steam is sufficient to reach a temperature of at least 50°C, particularly 95°C at the center of the volume, all the larvae are killed.

[0059] The difference in duration of contact with steam nevertheless produces differences when the slaughtered larvae are used for the manufacture of a wet food of the pâté type as explained later.

[0060] All the larvae killed by heat are then placed in an enclosure at a temperature below 10°C, for example equal to 3°C. When they are at the temperature of the enclosure, they are either flash-frozen at -30°C, or flash-frozen at -20°C (freezing time: 12h to 24h) and then stored at -18°C or -20°C.

[0061] The larvae killed by steam and by immersion in water retain a stable white-beige color and do not turn brown, either during cooling or in the frozen state.

[0062] 2) Test of the influence of the slaughtering method on the physico- characteristics

[0063] chemicals of a wet food preparation

[0064] The following ten tests were carried out:

[0065] 1. Larvae placed in a cold room at 4°C for a minimum of 12 hours before slaughter, then

[0066] slaughtered by mechanical freezing at -30°C - (reference 1.1F)

[0067] 2. Larvae placed for a minimum of 12 hours before slaughter in a cold room at 4°C then

[0068] slaughtered by cryogenic freezing at -60°C - (reference 2.1)

[0069] 3. Larvae at room temperature killed by short steam blanching

[0070] (5 min / 100°C) then mechanical freezing -30°C - (reference 3.1S)

[0071] 4. Larvae at room temperature killed by short steam blanching

[0072] (5 min / 100°C) then freezing at -20°C cold room - (reference 3.1C)

[0073] 5. Larvae at room temperature killed by prolonged steam blanching

[0074] (10 min / 100°C) then mechanical freezing -30°C - (reference 3.2S)

[0075] 6. Larvae at room temperature killed by prolonged steam blanching

[0076] (10 min / 100°C) then freezing at -20°C cold room - (reference 3.2C)

[0077] 7. Larvae at room temperature killed by short water blanching

[0078] (3 min / 100°C) then mechanical freezing -30°C - (reference 4.1S)

[0079] 8. Larvae at room temperature killed by short water blanching

[0080] (3 min / 100°C) then freezing at -20°C cold room - (reference 4.1C)

[0081] 9. Larvae at room temperature killed by prolonged water blanching

[0082] (6 min / 100°C) then mechanical freezing -30°C - (reference 4.2S)

[0083] 10. Larvae at room temperature killed by prolonged water blanching (6 min / 100°C) then freezing at -20°C in a cold room - (reference 4.2C)

[0084] In all cases, the volume of larvae killed by steam is 27.5cm x 47cm x 3.5cm (W x L x H). The larvae are placed in a stainless steel container having these internal dimensions.

[0085] The larvae, bleached in hot water, are placed in a net, which is immersed in 10 litres of water at 100°C. The mass of larvae is 1.5 kg. Bacteriological analyses

[0086] Analyses aimed at quantifying the mesophilic aerobic flora at 30°C per gram of larva were carried out on larvae killed by steam and on larvae killed by cold. The analyses were performed according to standard NF EN ISO 4833-1 and European Regulation 2073 / 2005 as amended.

[0087] For larvae killed by steam, the quantity of mesophilic flora measured is less than 10 CFU. For larvae killed by cold, the quantity of mesophilic flora measured is greater than 30,000 CFU.

[0088] Manufacture of a wet food preparation of the cat pâté type

[0089] Slaughtered and frozen (-20°C or -30°C) larvae are used without thawing for To prepare a wet food preparation similar to pâté. In this case, this wet preparation is intended for a cat; it is therefore a cat pâté.

[0090] The method for manufacturing the wet food preparation is as follows.

[0091] Sorghum grains are ground using a food processor / chopper. The resulting sorghum powder is pre-mixed with brewer's yeast, an attractant (containing sugar), and a vitamin mixture using a Stephan cutter at 500 rpm for 30 seconds at 20°C. The frozen larvae, water, carrots, and the Frozen apples are pureed and blended with a Stephan food processor at 3000 rpm for 1 to 2 minutes. The mixture temperature should be between 0 and 2°C. The mixture is then filled with the resulting mixture into small, low-profile metal cans. The metal lids (equipped with an easy-to-use seal, requiring no can opener) are then crimped onto the cans. The cans are then placed in a Brouillon brand vertical autoclave on program 3 for 1 hour and 47 minutes. For at least 24 minutes, the cans are subjected to a temperature of 127°C, ensuring sterilization and cooking of the ingredients.

[0092] The composition of the pâtés is indicated in Table 2 below.

[0093] [Tables2] Ingredients Supplier g per 100g of finished product Frozen / frozen larvae Fungfeed 62.0 Water / 28.8 Sorghum grain Loos feed 4.0 Frozen carrots METRO 3.0 Frozen apples METRO 2.0 Gerblé brewer's yeast 0.2 Palatability 2.0 Vitamin mix 1.0

[0094] Autoclaving sterilizes the food composition contained in the cans. The pH of all preparations was found to be stable (pH value: between 6.1 and 6.4). The pâtés can be stored for two years.

[0095] Table 3 below indicates the times required to obtain a core temperature of 127°C in the aforementioned 200g boxes. The time indicated in Table 3 is the sterilizing value.

[0096] [Tables3] Larvae batch 1, 1F Larvae batch s 2.1 Larvae batch 3, 1S Larvae batch 3.1C Larvae batch 3.2S Duration Not tracked 29.5 min Not tracked 35.8 min Not tracked Larvae batch 3.2C Larvae batch 4.1S Larvae batch 4.1C Larvae batch 4.2S Larvae batch 4.2C Duration 36.9 min Not tracked 28.3 min Not tracked Not tracked

[0097] In view of the results in Table 3, it can be seen that the sterilizing value is higher for larvae killed with steam than that obtained for larvae killed by freezing or by immersion in hot water. This difference may be due to a higher water content in larvae blanched with hot water, as they absorb water during the blanching process. However, water content does not explain the difference in sterilizing value between larvae killed by steam and larvae killed by freezing, which also have low or even zero water absorption. It can therefore be inferred that the different heat transfer results from a different chemical composition of the larvae, which, surprisingly, stems from the killing method used. Without the Applicant being bound by the following explanation, it is also possible that the osmotic pressure is lower during steam treatment than during immersion in hot water.Steam-treated larvae retain their water (the same water content as live larvae), and this water is bound and therefore not biologically available. Conversely, submerged larvae become engorged with water, which is then released during drainage due to the larva's permeability to water. The water contained in immersion-bleached larvae is therefore free water, which is reflected in the water activity measurement, which is higher in immersion-bleached larvae than in steam-treated larvae.

[0098]

[0099] Various characteristics of the mash were then studied. Table 4 below provides a brief summary. Lot of 1 Arves Texture Black rind Color Other Pieces in the mouth Gray film 1.1F Slicable but crumbly Yes Gray No No 2.1 Slicable and less crumbly than 1.1F Yes Gray No No 3.1S Slicable less crumbly than 1.1F and 2.1 No Brown Gray Turns quickly to gray-green, mud color Yes Yes 3.1C Slicable and spreadable No Caramel brown Does not change No oxidation Yes Yes 3.2S Slicable and spreadable No Caramel brown Does not change No oxidation Yes No 3.2C Slicable and spreadable Not brown because it is more homogeneous than 3.2S Does not change color - No oxidation Yes No 4.1S Slicable and spreadable Not brown because it is not brown - No oxidation Yes No 4.1C Slicable and spreadable Not brown because it is not brown - No oxidation Yes No 4.2S Slicable and spreadable but sticks to the can No brown because it is not brown - No oxidation Yes No 4.2C Slicable and spreadable but sticks to the can No Caramel brown Does not change color - No oxidation Yes No

[0100] Figures 1 and 2 show photographs of the surfaces of freshly opened food containers. In [Fig. 1], a black crust has formed on the surface of the food not in contact with the lid. In [Fig. 2], which shows the food obtained with 3.1 S larvae, the gray film is thinner and covers the entire upper surface of the food block.

[0101] The odor was tested for all the pâtés. All the pâtés gave off an appetizing odor indicative of the Maillard-type reactions that took place during the cooking-sterilization of the pâté. An odor of toasted bread and toasted cereals was detected.

[0102] However, for the preparations obtained with the batches of cold-killed larvae, a slight pharmacy odor is detected, probably emitted by the vitamin mixture.

[0103] This odor does not appear for the pastes obtained from larvae slaughtered by blanching in water at 95°C or treated with steam according to the process of the invention.

[0104] The strong odor of the pharmacy, as well as the presence of the black crust, renders the pâtés unfit for sale; the consumer is too likely to associate the presence of the black crust with poor product quality or its expiration date. It is probable that the black crust is due to enzymatic processes, for example, polyphenol oxidase, which is not damaged by the cold but is damaged by the heat. The Plaintiff is nevertheless not bound by this explanation.

[0105] The presence of the grey film also seems to indicate the persistence of enzymatic reactions, but to a lesser extent. The color change in air seems to indicate an oxidation reaction, which, surprisingly, does not occur when the contact time with vapor is longer.

[0106] The texture of the pâté should be neither too crumbly, nor too sticky, nor too dry. Cats have difficulty ingesting sticky food. Crumbly pâté is inconvenient for the owner, who struggles to accurately measure the amount at one time without spilling it everywhere because it crumbles. Pâtés made with larvae killed by immersion in hot water for 6 minutes are too sticky to be favored by cats and their owners.

[0107] Surprisingly, the method of larval slaughter influences the physicochemical properties of the slaughtered larvae. This influence is reflected in various characteristics of the pastes obtained after cooking and sterilizing the slaughtered larvae. Larvae slaughtered according to the process of the invention produce a paste that is satisfactory in terms of odor, consistency, and visual appearance (absence of a crust). When the contact time with steam is 10 minutes, the paste obtained has a color that is also satisfactory to the consumer (caramel brown) and stable over time, without visible oxidation.

[0108] 3) Physicochemical characterization of the slaughtered larvae

[0109] A) Water intake of larvae killed by steam

[0110] For 3 kg of fresh, live larvae killed by exposure to steam at 100°C for 10 minutes, the average weight of the killed larvae is 3320 g (standard deviation of 43.6). The mass of water accumulated in the larvae is therefore 320 g, which corresponds to an average water uptake (water uptake = mass of water / mass of fresh larvae x₀) of 10.67%. After freezing at -20°C, the average mass of the larvae is 3192 g with a standard deviation of 39.8 g. Water loss is observed during freezing. After the freezing stage, the average water uptake is 6.4%. [YES] B) Density

[0112] The density of slaughtered and frozen larvae at -20°C was measured using a specific container. The container is filled with water and weighed. It is then emptied and filled with larvae, and weighed again. The ratio of the two measurements gives the density.

[0113] Density of larvae killed by steam at 100°C for 10 min then frozen at -20°C: 301.54g / L / 311.20 g / L / 319.64 g / L (average value 310.8 g / L standard deviation of 9.1 g / L)

[0114] Density of larvae killed by blanching by immersion in water at 95°C then freezing at -20°C: 410.50 g / L / 410.56 g / L / 427.83 g / L (average value 416.3 g / L standard deviation 10.0 g / L)

[0115] C) Water activity on whole larvae

[0116] Water activity was measured according to an internal MMIT 033B method adapted from standard NF ISO 18787: 2017. The determination of water activity (Aw) is carried out on the whole thawed product.

[0117] This is a dew point measurement (Aqualab 4TE Decagon): the sample is introduced into a sealed measuring chamber containing a mirror whose temperature can be varied. The mirror is cooled until condensation appears on its surface. This Aw measurement technique is based on the fact that air can be cooled to its saturation point without changing its water content. At equilibrium, the relative humidity of the air in the chamber is equal to the water activity (Aw) of the sample. The exact temperature (dew point) at which water vapor condensation occurs is determined. The surface temperature of the sample is also recorded. From these two temperatures, the Aw can be determined.

[0118] The result is an average of 2 minimum determinations if A<0.01. The measurement is carried out at 25°C.

[0119] Values ​​measured for larvae killed by steam at 100°C for 10 min then frozen at -20°C: 0.968 / 0.976 / 0.981 average value 0.975 (measured after 78 days of freezing)

[0120] Values ​​measured for larvae killed by blanching by immersion in water at 95°C then freezing at -20°C: 0.990 / 0.997 average value 0.994 (measured after 146 days of freezing).

[0121] Since water activity tends to decrease during freezing (the longer a food is frozen, the more the water activity in that food decreases), it is observed that the larvae of the invention, which were frozen for a shorter time than those obtained by immersion and freezing, unexpectedly exhibit lower water activity.

[0122] D) Nutritional analyses of the larvae

[0123] The following Table 5 summarizes the results obtained. Larvae Steam slaughter Freezing slaughter Water immersion slaughter Energy value (kcal / 100g) 181 210 202 Protein (g / 100g) / Total Nitrogen (g / 100g) 21.0 (±0.7) / 3.3 6 (±0.12) 18.6 (±0.7) / 2.98 (±0.11) 22.5 (±0.8) / 3.61 (±0.12) Total Carbohydrate (g / 100g) / Assimilable Carbohydrate (g / 100g) 4.4 / 4.4 2.7 / 2.7 3.6 / 3.6 Fat (g / 100g) 8.9 (±0.7) 13.8 (±0.8) 10.9 (±0.8) Ash (g / 100g) 1.35 (±0.18) 1.14 (±0.17) 1.41 (±0.18) Moisture (g / 100g) 64.4 (±0.7) 63.7 (±0.7) 61.6 (±0.7)

[0125] The calculation of the energy value is implemented in accordance with EU Regulation No. 1169 / 2011. The protein content is calculated by nitrogen titration using the Kjeldahl method. The carbohydrate content is calculated by subtracting the other contents from the total carbohydrate content. The lipid content is determined by microwave gravimetry. The sample is hydrolyzed, and then an extraction is performed using sulfuric acid and cyclohexane via microwave irradiation. The fat content is then determined by weighing after evaporation of the cyclohexane. The ash content is determined by thermogravimetry at 550°C for 4 hours. The moisture content is determined by thermogravimetry at 70°C.

[0126] The analyses are performed on the larvae after they have been killed, frozen, and then thawed.

[0127] The larvae killed by flash freezing remained frozen for 146 days. The larvae killed by steam remained frozen for 78 days, and the larvae killed by immersion remained frozen for 146 days before the analyses.

[0128] In view of the results in Table 5 above, it is surprisingly observed that the larvae killed using the method of the invention contain less protein than larvae killed by freezing, less lipids and more minerals than larvae killed and frozen by other methods. They also contain more water than the other killed larvae, which is surprising because it was plausible that larvae killed by immersion would absorb water more readily.

[0129] Steam-killed larvae were subjected to steam at 100°C for 10 min. Immersion-killed larvae were immersed for 2 min at 95°C.

Claims

Claims

1. Method for slaughtering and preserving insect larvae and / or insects which are arranged so as to form a volume, characterized in that said volume of insect larvae and / or insects is subjected to water vapor at 100°C for a time tl sufficient for the temperature inside said volume and in particular at the center of said volume to reach a value equal to or greater than 50°C and in particular equal to 60°C, 70°C, 80°C, 90°C or 95°C, in that said slaughtered larvae and / or insects are deep-frozen, optionally after cooling them to a given temperature and in that said slaughtered and frozen larvae and / or insects are stored at a negative temperature.

2. Method according to claim 1, characterized in that the temperature at the center of said volume is maintained at a value greater than 50°C and in particular equal to 60°C, 70°C, 80°C, 90°C or 95°C for a duration t2 such that the total duration of the steam treatment step is greater than or equal to 6 min, 7 min, 8 min, 9 min, 10 min, 11 min and less than or equal to 20 min.

3. Method according to any one of the preceding claims, characterized in that said insects and / or said larvae are chosen from the following insects and / or larvae: the black soldier fly (Hermetia lllucens), the house fly (Musca domestica), the mealworm (Tenebrio molitor), the small darkling beetle (Alphitobius diaperinus), the house cricket (Acheta domesticus), the tropical house cricket (Gryllodes sigillatus), the steppe cricket (Gryllus assimilis) and mixtures of larvae and / or insects of at least two of said insects.

4. Method according to any one of the preceding claims, characterized in that said volume of larvae and / or insects is substantially equal to or greater than 4000 cm3 and less than or equal to 5000 cm3.

5. Method according to any one of the preceding claims, characterized in that it is carried out in a steam oven, the larvae and / or insects being arranged in a thermally conductive container.

6. Method according to any one of the preceding claims, characterized in that the duration of the steam treatment is such that the water intake of the larvae and / or insects after steam treatment and before freezing / deep-freezing is less than or equal to 20%, in particular less than or equal to 15% and equal to or greater than 7%.

7. Method according to any one of the preceding claims, characterized in that said freezing / deep-freezing step is carried out in such a way that the water intake of said larva and / or said slaughtered and frozen / deep-frozen insect is substantially equal to or greater than 3%, in particular substantially equal to 5% and substantially equal to or less than 9% and in particular substantially equal to 7%.

8. Slaughtered and frozen / deep-frozen larvae and / or insects obtainable according to the method according to any one of claims 1 to 7, characterized in that they have at least one characteristic from among: a water activity equal to or greater than 0.960 and equal to or less than 0.981, an energy value less than or equal to 210 kcal / 100g, a carbohydrate content greater than or equal to 4.0 g / 100g, a lipid content less than or equal to 10g / 100g, a protein content less than or equal to 22 g / 100g, a density equal to or greater than 295 and equal to or less than 325.

9. Process for manufacturing a food characterized in that larvae and / or insects according to claim 8 are reduced to pieces and in that said pieces are mixed with a food composition which contains a flour of at least one cereal and at least one fruit and / or at least one vegetable, in particular at least one frozen fruit and / or at least one vegetable and in that said mixture is cooked.

10. Dry or wet food obtained after cooking / sterilization according to the method of claim 9.

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