Methods for producing insect powder or granulate

Abstract

The present invention relates to: methods for producing an insect powder or granulate; correspondingly produced insect powders or granulates; and food or feed containing said insect powders or granulates.

Description

[0001] Process for the production of insect powder or granules

[0002] The present invention relates to processes for producing an insect powder or granules, insect powders or granules produced accordingly, and food or feed containing them.

[0003] Today, intensive agriculture poses a significant environmental problem. In particular, the rearing of livestock for meat production produces environmentally harmful gases through the release of methane and nitrogen compounds from animal digestion. Furthermore, the application of nitrogenous compounds through manure and slurry leads to significant problems. This not only increases the nitrate content in groundwater but also disrupts the nitrogen balance in the environment. For this reason, the Netherlands, for example, as a heavily agricultural country, had to introduce speed limits of 100 km / h on motorways to prevent this effect from being exacerbated by traffic-related environmental pollution.

[0004] Nitrogen is undoubtedly an important element, as it is needed by plants, for example, for protein biosynthesis. However, the amount of nitrogen required in soils and the amount of nitrogen that must be applied from livestock farming are disproportionate. Moreover, the nitrogen compounds contained in manure and slurry are suboptimal anyway.

[0005] Corresponding regulatory mechanisms by environmental authorities encounter the problem that a reduction in manure and slurry would also require a reduction in animal husbandry. On the other hand, however, the human body requires lysine as an essential, first-limiting amino acid, which is primarily found in meat and other animal protein sources. A lack of lysine and a declining consumption of other essential amino acids and fatty acids lead to a deterioration in human health and intellectual abilities. Thus, with few exceptions, the most important essential amino acids are found in animal protein. One plant-based exception is soy, which, however, is not conducive to the goal of improving the environmental balance.

[0006] Furthermore, the production of conventional (animal) proteins is also expensive and requires a lot of raw materials. Therefore, significant agricultural land and high-quality raw materials are required, so in most cases, performance-enhancing ingredients are needed to optimize protein or meat production. Thus, a cow requires approximately 6 kg of feed, a pig approximately 3 kg of feed, and a chicken approximately 1.6 kg of feed for every 1 kg of meat to be produced. This, in turn, requires a high protein content of the forage plants and valuable supplements of vitamins and other additives.

[0007] Now, farm animals such as pigs and chickens also require essential amino acids to produce protein. Since the BSE crisis, meat meal has been banned in livestock farming, soy or fish meal can be used as a source of lysine and methionine. However, soy promotes deforestation and must be imported from Brazil, while fish meal promotes overfishing of the world's oceans and is predominantly imported from Chile.

[0008] Insects, on the other hand, contain a very favorable distribution of essential amino acids and fatty acids. According to current technology, they require approximately 1.5 kg of feed per kg of meat, which has now been improved to approximately 1 kg of feed per kg of meat, and some farmers are already implementing this approach. Since their feed conversion efficiency is significantly higher than with conventional livestock, the proportion of by-products and residues is also significantly higher quality and lower.

[0009] Despite great efforts, the implementation of these advantages encounters great difficulties regarding production, shelf life, microbiological contamination, and acceptance of insect-based feed and food. Currently, two methods for producing a protein powder from

[0010] Insect larvae denied.

[0011] In the so-called wet process, the larvae are first boiled in water. This step serves to sanitize the larvae. They are then pressed in a decanter or oil press, and the water fraction, oil fraction, and solid fraction are separated. Depending on the quality, the water fraction is then freed of residual substances and discharged into the wastewater. The oil fraction also requires further processing, for example, by centrifugation or filtration, as it also does not contain 100% oil. The solid fraction is then freed of residual moisture using a dryer, usually at around 60°C. This process typically produces four fractions: the oils, the skin residue, the protein powder, and the water. The quality of the protein powder is usually rather poor, with a gray-brown color and a fishy odor. Furthermore, some of the essential amino acids of the raw larvae are no longer present, and the protein content is only around 58%.The protein powder is highly reactive with atmospheric oxygen, causing it to quickly discolor and develop unpleasant odors. Its taste is very acidic. Adding oils to the protein powder creates a sticky mass. However, this process loses the beneficial preservative properties of certain oleic acids contained in the raw larvae, and the oil is no longer as high-quality as the lab values ​​of the raw larvae. The skin is light beige in color with a high cellulose content.

[0012] In the dry process, the larvae are usually first boiled to sanitize them and then dried at low heat. The oil is then removed, usually using a decanter or oil press. This produces an oil portion and a dry portion. The oil portion usually contains proteins and suspended particles. The dry portion usually has a very strong odor and has lost some of its amino acids. The protein content is usually around 53% and the product is dark gray.

[0013] In this context, the document DE 10 2020 004 957 A1 describes a process for the industrial breeding of the black soldier fly and for further processing its larvae into insect meal. Furthermore, the document EP 3 078 277 A1 describes a process for producing insect powder, comprising drying insects with air at a temperature of 100°C to 180°C and grinding the insects into a powder, wherein the powder has a water activity of less than 0.7. The document US 2018 / 303126 A1 describes a process for the heat treatment of a composition containing chitin and water-soluble vitamins and / or derivatives thereof. Finally, the document Kantrong et al. (Kantrong, H. et al.', Journal of Food Science and Technology, 59; pp. 2209-2219; August 16, 2021 ) investigated the influence of extrusion temperature and puffing technique on the properties of a snack made from purple sweet potato and butterfly flowers.

[0014] The present invention is therefore based on the object of providing applicable and consumer-friendly products based on insects that can be marketed as feed or food, as well as processes for their production.

[0015] This object is achieved by the embodiments characterized in the claims. In particular, methods according to the invention for producing an insect powder or granulate, correspondingly produced insect powders or granules, and food or feed containing them are provided.

[0016] Accordingly, one aspect of the present invention relates to a process for producing an insect powder or granule, comprising the step of heat-treating insect larvae at a temperature of 100°C to 400°C for a period of 10 minutes or less and 10 seconds or more, thereby simultaneously drying and pasteurizing the insect larvae.

[0017] This method preferably comprises the steps:

[0018] (a) Providing insect larvae,

[0019] (b) heat-treating the insect larvae provided in step (a) at a temperature of 100°C to 400°C for a period of 10 minutes or less and 10 seconds or more, thereby simultaneously drying and pasteurising the insect larvae, and

[0020] (c) grinding or granulating the heat-treated insect larvae obtained in step (b).

[0021] The insect larvae provided in step (a) of the process according to the invention can be any insect larvae or mixtures of insect larvae suitable for producing an insect powder or granules for use as food or feed. In preferred embodiments, the insect larvae are selected from the group consisting of fly larvae (Brachycera), larvae of stored product pests, cricket larvae (Grylloidae), and mixtures thereof. The term "stored product pests" includes, for example, bread beetles, dried fruit moths, pea beetles, peanut seed beetles, common larder beetles, grain capuchins, grain moths, storage moths, grain flat beetles, flour beetles, Khapra beetles, small tobacco beetles, grain moths, corn weevils, flour beetles, rice weevils, red-brown flat beetles, Turkish flat beetles, red-brown / American flour beetles, black grain rodents, edible bean beetles, and storage mites.In particularly preferred embodiments, the insect larvae are selected from the group consisting of larvae of the black soldier fly (Hermetia illucens), larvae of the flour beetle (Tenebrio molitor), larvae of the flour beetle (Tribolium castaneum), larvae of the house cricket (Acheta domesticus) and mixtures thereof.

[0022] The insect larvae provided in step (a) of the process according to the invention are preferably washed beforehand. Methods for washing insect larvae are not subject to any particular restrictions and are known in the art. Suitable methods include, for example, washing with water, air, gases, brushes, or abrasive particles. In specific embodiments, cold water with a temperature of 8°C or less, preferably 6°C or less, 4°C or less, 2°C or less, or 0°C is used. This frees the larvae from surface contamination and simultaneously puts them into deep sleep. The insect larvae are preferably killed after step (a) and before step (b) of the process according to the invention. This can be carried out in the form of nitrogen, pressure, gas, or heat disinfestation, as known in the art.In a particular embodiment, however, the insect larvae are only killed by the heat treatment in step (b) of the process according to the invention.

[0023] In certain embodiments, the process according to the invention further comprises a step of mechanical water reduction by means of an oil press, centrifuge, filter press, screw press, and / or a decanter prior to step (b). Processes for mechanical water reduction are not subject to any particular restrictions and are known in the art. Preferably, the water content of the larvae is reduced in this step by 30% or less, 40% or less, or 50% or less, although a reduction in the water content of more than 50% should be avoided. For example, in the case of larvae with a typical water content of approximately 70% (w / w), the water content is reduced such that after this step the water content of the larvae is approximately 50% (w / w), approximately 40% (w / w), or approximately 35% (w / w).

[0024] In certain embodiments, the oil contained in the larvae is simultaneously removed during the aforementioned mechanical water reduction step. The oil content of the larvae after this step should be approximately 12% (w / w) or less, preferably 10% (w / w) or less, more preferably 8% (w / w) or less, more preferably 5% (w / w) or less. The oil component can be separated from the water component, for example, using disc separators. The oil can then either be added back to the larvae or treated as a separate end product.

[0025] In step (b) of the process according to the invention, the insect larvae provided in step (a) are heat-treated at a temperature of 100°C to 400°C for a duration of 10 minutes or less and 10 seconds or more, thereby simultaneously drying and pasteurizing the insect larvae. This heat-treatment is preferably carried out at a temperature and for a duration that results in a residual moisture content of the insect larvae of 20% (w / w), preferably 18% (w / w) or less, more preferably 15% (w / w) or less, more preferably 12% (w / w) or less, more preferably 10% (w / w) or less, for example, about 8% (w / w). Corresponding results can be achieved by suitable selection of the temperature and duration of the heat-treatment.

[0026] The heat treatment can also be carried out with an ascending or descending, step-like, or continuous temperature gradient in the range of 100°C to 400°C. This can, for example, be carried out in the form of a six-step, descending temperature gradient from 280°C to 120°C.

[0027] In preferred embodiments, the heat treatment in step (b) is carried out at a temperature of 120°C or higher, 140°C or higher, 160°C or higher, 180°C or higher, or 200°C or higher, for example at about 220°C, wherein a maximum temperature of 400°C, preferably 380°C, more preferably 360°C should not be exceeded.

[0028] The duration of the heat treatment in step (b) is preferably 10 minutes or less, 6 minutes or less, 4 minutes or less, 3 minutes or less, 2 minutes or less, or 1 minute or less, whereby the duration should not be less than 10 seconds, preferably a duration of 30 seconds.

[0029] Suitable combinations of temperatures and / or temperature gradients and corresponding drying times (duration of heat treatment) can be readily selected by the skilled person and preferably lead to the residual moisture contents defined above. Higher drying temperatures result in shorter drying times, and vice versa.

[0030] For example, in the case of insect larvae with a water content of 65 to 70% (w / w), a drying time of approximately 90 seconds results with a decreasing temperature gradient from 380°C to 120°C. With an increasing temperature gradient from 320°C to 120°C, the corresponding drying time is 110 seconds. Experience has shown that these values ​​vary depending on the choice of drying machine and the length of the machine's treatment. If the machine uses cooling air, the drying time or the temperature must be increased, as the cooling energy is minimized accordingly.

[0031] Processes for heat treatment / drying insect larvae are not subject to any particular restrictions and are known in the art. The same applies to devices used in such processes. In particular, any dryer variant can be used that has an introduction temperature higher than 120°C, preferably an introduction temperature higher than 130°C, 180°C, or 200°C, and continuously moves the product particles.

[0032] Suitable processes include, for example, heat treatment using a planetary roller extruder or a thin-film dryer. As an alternative to a planetary roller extruder, multi-screw, twin-screw, or single-screw extruders can also be used, provided they have venting zones and jacket or shaft heaters. Mill dryers, disc dryers, tube dryers, drum dryers, fluidized-bed dryers, belt dryers, microwave disc dryers, or fluidized-bed dryers can also be used. In principle, all dryer variants with a rotating rotor and a corresponding outer shell can be used. Dryer variants that move the product with air streams are also suitable.

[0033] As described above, thin-film dryers can also be used in this context. However, this has the disadvantage that the drying energy is significantly increased by the air flow. In addition, the skin and larval residue separate during the process, which then requires further processing. These machines are continuous dryers that convey the material to be dried through the drying zone using a high-speed rotor and are characterized by a short treatment time and the possibility of a higher treatment temperature of more than 100°C. They can also be operated with air-excluding gases such as nitrogen or helium. It is also possible to use these rotor dryers in a batch process or in a

[0034] to operate vacuum.

[0035] Conventional heat treatment / drying processes typically involve low-temperature machines with either long treatment times or low throughput. Thus, the most common design model is usually a belt dryer, such as a microwave disk dryer or a mill dryer based on the drying rotor principle.

[0036] Planetary roller extruders are well-known, for example, from Entex or Battenfeld-Cincinetti. Thin-film dryers are also well-known, for example, from Vomm, SMS-Buss-Canzler, or GIG-Karasek. Mill-dryer variants, such as the Ultra-Rotor from Jäckering or similar versions from Hosokawa-Alpine, Giesinger, or Pallmann, are also well-known.

[0037] In step (c) of the process according to the invention, the heat-treated insect larvae obtained in step (b) are ground or granulated. Processes for grinding or granulating the insect larvae are not subject to any particular restrictions and are known in the art. These include, for example, the use of a universal mill, pin mill, turbo mill, knife mill, cross-beam mill, hammer mill, a roller mill, or a disk mill. Very good results can also be achieved with a planetary roller extruder. Accordingly, in a particular embodiment, both steps (b) and step (c) of the process according to the invention are carried out using a planetary roller extruder. As an alternative to a planetary roller extruder, multi-screw, twin-screw, or single-screw extruders can also be used, provided they have venting zones and jacket or shaft heating elements.Furthermore, roller systems or pellet presses such as ring or flat-die presses can also be used. The particle size of the insect powder or granules produced according to the invention is, in the case of a powder, preferably 500 μm or less, more preferably 200 μm or less, 150 μm or less, or 75 μm or less. In the case of granules, the particle size is more than 500 μm, preferably 1 mm or more, 2 mm or more, 3 mm or more, or 5 mm or more. Methods for determining the particle size of a powder or granule are known in the art.

[0038] In certain embodiments, the process according to the invention further comprises a step of deoiling the resulting insect powder or granules after step (c). Deoiling processes are not subject to any particular restrictions and are known in the art. Preferably, the oil content of the resulting product after this step is 25 to 20% (w / w), more preferably 20 to 15% (w / w) or 15 to 10% (w / w).

[0039] In preferred embodiments, the insect powder or granulate produced according to the invention contains

[0040] (i) less than 10 CFU / g (colony forming units per gram) of Clostridium perfringens,

[0041] (ii) less than 100 CFU / g Enterobactericeae sp., and / or

[0042] (iii) no detectable Salmonella (Salmonella sp.).

[0043] Furthermore, the insect powder or granulate produced according to the invention preferably contains

[0044] (iv) no detectable pesticides,

[0045] (v) no detectable viruses,

[0046] (vi) less than 0.15 mg / kg lead,

[0047] (vii) less than 0.05 mg / kg cadmium, and / or

[0048] (viii) less than 0.05 mg / kg mercury.

[0049] Methods for determining corresponding microorganisms in the insect powder or granules are known in the art, as are methods for determining pesticides, viruses, lead, cadmium and mercury in the insect powder or granules.

[0050] A further object of the present invention relates to an insect powder or granulate which has been obtained by the process according to the invention.

[0051] All relevant restrictions defined for the process according to the invention also apply to the insect powder or granulate according to the invention. This applies in particular to the underlying insect larvae, water and oil content, particle size and microbiological properties.

[0052] The present invention further relates to a food or feed containing the insect powder or granules according to the invention. Suitable food or feed are not subject to any particular restrictions and include, for example, pig feed, fish feed, poultry feed, dog food, cat food, hare food, rabbit food, rodent food, protein shakes, minced meat substitutes, and meat and sausage substitutes.

[0053] The term "about" as used herein represents a modifier of the specified value of ± 10%, preferably ± 9%, ± 8%, ± 7%, ± 6%, ± 5%, ± 4%, ± 3%, ± 2%, ± 1.5%, ± 1% or ± 0.5%. Thus, for example, the phrase "about 100" denotes a range of values ​​from 90 to 110.

[0054] The present invention provides methods for producing an insect powder or granules, insect powders or granules produced accordingly, and food or feed containing them.

[0055] Insect larvae are typically fed or marketed live, frozen, or fresh (dead). Pet stores, for example, offer live insects, their larvae, and even preserved animals. In livestock farming, the feeding of live food animals has been significantly restricted. Therefore, they must now be professionally and ethically killed before they can be used as feed. However, slaughtered animals have a very short shelf life and are therefore difficult to market. Furthermore, the high water content poses an economic problem, as approximately 70% water per kg of larvae is fed and therefore transported. To counteract these examples, the larvae must be offered as dry matter with a maximum of 20% (w / w) moisture content, preferably a maximum of 15% (w / w).

[0056] The shelf life of the larvae is not only very limited by their water content. Their microbiological composition is also very unfavorable, because, like meat, the larvae can quickly contain or develop hazardous substances. Therefore, the larvae must not only be dried but also pasteurized. The microbiological load must be minimized or even deactivated.This can be achieved in several ways, for example by using a high drying temperature of over 90°C, 110°C, 125°C or 150°C, by applying pressures of 1 bar, 5 bar, 10 bar or 20 bar, by using chemical additives or ingredients, for example salt compounds such as calcium chloride, sodium chloride and sodium nitrite (E250), sodium nitrate and potassium nitrate (E251 and E252), sorbic acid and sorbates (E200 to E203), benzoic acid and benzoates (E210 to E213), all kinds of acids and bases such as wine (and tartaric acid), lemons (and citric acid), vinegar (and acetic acid), formic acid as well as all water-regulating or water activity (aw value)-reducing substances such as guar gum, xanthan gum, locust bean gum and also tannins.

[0057] Furthermore, the color of the final product plays a crucial role in feed and food. However, the larvae contain an enzyme that turns the larvae black after they are killed and their surface is destroyed. Since a black food color does not allow for color change through pigmentation to imitate other foods, a blackish or grayish color is not beneficial. In addition, the product gives an "unclean" or burnt impression. Therefore, it is important to drastically reduce this enzymatic activity. Several measures can be taken to reduce it. Temperature influences the speed of enzymatic reactions. At high temperatures, enzymes are usually denatured and lose their activity. At low temperatures, enzymes are inactivated and lose their activity.One way to reduce enzymatic activity, and thus blackening, is to heat or freeze the food. Furthermore, the pH value influences the structure and function of enzymes. Every enzyme has an optimal pH value at which it works best. pH values ​​that are too acidic or too alkaline can denature or inhibit enzymes. One way to reduce enzymatic activity is to acidify or alkalize the food with vinegar, lemon juice, baking soda, or other acids or bases. Water activity also influences the availability of water for the enzymatic reaction. The higher the water activity, the higher the enzymatic activity. One way to reduce enzymatic activity is to dry, dehydrate, salt, or add sugar to the food. Finally, inhibitors are substances that bind to the enzyme and reduce or block its activity.There are different types of inhibitors, such as competitive inhibitors, non-competitive inhibitors, or allosteric inhibitors. One way to reduce enzymatic activity is to add inhibitors such as metal ions, sulfur compounds, phenols, or other natural or synthetic substances.

[0058] Odor is a crucial characteristic for all types of potential feed or food. Because insect larvae are a flesh-like substance, this factor is very sensitive and quickly develops very unpleasant odors. Since the microbiological and enzymatic composition of the larvae is also very unfavorable in this regard, conventionally dried larvae develop unbearable and very intense odors. To minimize these odors, all of the measures listed above must ideally be combined. Therefore, the larvae must be pasteurized and, if necessary, chemically adjusted to limit or even deactivate the odor. Taste is the most crucial characteristic of any feed or food and, in the case of insect larvae, has the same properties as the smell.However, the inherent taste is another factor to consider, as insect larvae generally have a very sour taste. Therefore, pH-regulating substances can only be used if they do not intensify or alter the inherent taste too much.

[0059] The most important and economically relevant ingredient in insect-based feed or food is protein. Therefore, it is important to preserve it as intact as possible, as proteins quickly denature / coagulate at the high temperatures of pasteurization. This often results in a loss of their value and thus their economic viability. Therefore, protein-containing substances are typically dried at a maximum of 60°C, as 58°C is the coagulation temperature.

[0060] However, the invention has shown that the drying time plays a crucial role. A balance must be established here: on the one hand, the temperature must be high enough to evaporate water as quickly as possible, which is the case, for example, at 300°C, 250°C, 200°C, 150°C, or 120°C. On the other hand, the proteins of the enzymes and microorganisms contained within must be denatured, but not the important amino acids and other substances contained therein.

[0061] In this context, for example, excellent results are achieved at a drying temperature of 220°C in a contact dryer with an internal rotor. This produces shell fragments as the entire skin of the larva and a powder of the contents (meat). These can be separated and utilized. However, the skin usually has to be further processed into a powder and classified. This can be done using a universal mill (Condux-Netzsch, Pallmann PSKM, or others), a pin mill, a turbo mill, a knife mill, a cross beater mill, a hammer mill, a roller mill, or a disc mill. Very good results can also be achieved with a planetary roller extruder. This offers further advantages, but also disadvantages. Although the skin is not separated, the energy is better introduced because a planetary roller extruder has a larger surface area.Furthermore, it can be adjusted according to zones and energy input, and the drying time and intensity are also variable. The product can also be granulated directly into granules, animal feed, or even food. Powder production is also possible, although these must first be ground in a mill. After treatment in a planetary roller extruder or contact dryer, cooling is necessary. This is achieved using underwater cooling, strand cooling, air cooling, belt coolers, box coolers, flap coolers, roof coolers, or even separator cyclone cooling.

[0062] A freeze dryer can also be used as a dryer. These typically dry at temperatures below freezing. While freeze-drying produces very good basic results, it does not solve the problems of microbiological properties. Furthermore, it is very uneconomical and expensive. Vacuum dryers can also be used for this purpose, provided they dry at temperatures higher than 90°C, 110°C, 130°C, or 150°C. However, vacuum dryers are significantly more energy-intensive and expensive.

[0063] Twin-screw or single-screw extruders can also be used as planetary roller extruders, provided they have venting zones and jacketed heaters. Their function is very similar to that of a planetary roller extruder.

[0064] A thorough cleaning is essential for quality, as the larvae are fattened in their own feces mixed with feed. Furthermore, hygiene standards among farmers are not very high. Therefore, the larvae must be washed. This is usually done with water, air, gases, brushes, or abrasive devices. Ice water at 8°C, 6°C, 4°C, 2°C, or 0°C can be used to euthanize the larvae. This removes surface dirt from the larvae and simultaneously puts them into a deep sleep. At the same time, abrasive devices such as brushes or similar can be used to assist the process. The wastewater can then be filtered and drained away. The same effect can also be achieved with cold air. Due to the freezing point, even significantly colder air, for example at 0°C, -5°C, -15°C, -20°C, or -25°C, can be used.

[0065] Insect larvae can be killed using nitrogen, pressure, gas, or heat. In nitrogen disinfestation, the stunned larva is killed by further exposure to cold. In pressure disinfestation, the larva is killed by a sudden change in positive or negative pressure of at least 5 bar, 10 bar, 15 bar, 20 bar, or 25 bar. When gas is used, the larva is killed by suffocation or chemical killing with poisons. Thermal killing can be achieved by drying, since insects have no body cooling mechanisms, such as sweating. Therefore, they die at temperatures as low as 58°C.

[0066] In the present invention, it was surprisingly discovered that insect larvae can be dried for a short period of time at significantly higher temperatures than previously usual. In addition to drying, the insect larvae are simultaneously pasteurized, which allows for advantageous microbiological properties. Furthermore, enzymes that could cause adverse coloration of the resulting product, as well as bacterial proteins, are denatured, while the insect larval proteins themselves remain unharmed. This enables a product with an appealing color, good odor and taste, good shelf life, and an advantageously unchanged amino acid composition compared to the raw larvae used.

[0067] The process according to the invention not only reduces pathogenic contamination but also pasteurizes the product. This not only makes the product more durable, but also kills pathogenic germs without damaging the proteins contained. Furthermore, the process reduces the contamination with pollutants such as heavy metals, radionuclides, pesticides, mycotoxins, and other harmful substances.

[0068] After the drying process, granulation can be performed. This is done using extruders such as single-screw, twin-screw, or multi-screw extruders, as well as planetary roller extruders. Granulation can also be performed using roller systems or pellet presses such as ring or flat-die presses. This process allows the dried larvae to be formed into any desired shape, which offers several advantages. For example, feed intake and feed conversion of animals are increased, as well as digestibility. This significantly improves storage life and shelf life. Safe processing for customers is also usually only guaranteed with granules. Furthermore, it reduces the risk of explosion, as fewer or no suspended particles are produced.

[0069] A cooler can also be used after processing. A cooler not only brings the final product to a suitable temperature, but also improves shelf life by reducing moisture, ensures storage stability by improving flow properties, and ensures granule stability.

[0070] The present invention is further explained by the following non-limiting examples.

[0071] Examples

[0072] In an initial experiment, raw larvae were washed and dried using a Vomm thin-film dryer (Turbo-Technology ES900) at 220°C for an effective drying time of 20 seconds. The larvae are fed into a cylinder by means of a dosing device. This contains a rotating rotor whose speed can be controlled by a frequency converter to regulate the throughput time. The larvae are grasped, pressed against the wall of the dryer cylinder, heated to 220°C, and applied to form an even layer. The air generated by the rotor extracts the water vapor. Once this layer has passed through the dryer, a dry powder of the larval interior and the entire skin of the individual larvae is discharged. The time and temperature were adjusted to achieve an initial moisture content of approximately 14% (w / w).

[0073] Result / properties of the product obtained:

[0074] Color: light beige, light brown

[0075] Smell: Chocolate, Coconut

[0076] Taste: pleasant, slightly sour

[0077] Protein content 47% (w / w) in dry matter

[0078] Amino acid composition: unchanged from the raw larva

[0079] Moisture content: 14% (w / w)

[0080] Oil content: 20% (w / w) in dry matter

[0081] Consistency: Powder and flaky skin

[0082] The resulting product was then subjected to granulability tests using single-screw extruders, twin-screw extruders, and pellet presses. A dog food product was also produced.

[0083] Result / properties of the product obtained:

[0084] Consistency: stable granules

[0085] Improved throughput compared to other powders

[0086] Dog food made from 100% larvae was very well accepted by all dogs tested

[0087] A grinding test was then carried out using a universal mill to crush the skin.

[0088] Result / properties of the product obtained:

[0089] Consistency: fine powder

[0090] Light beige color of the total powder

[0091] Consistent quality

[0092] In a second experiment, raw larvae were washed and dried using an Entex planetary roller extruder (TP / WE 70 / 800 M2 RG) at 220°C for an effective drying time of 30 seconds. The larvae are fed into an extruder using planetary shaft technology via a dosing device. This extruder contains a rotating rotor whose speed can be controlled by a frequency converter to regulate the throughput time. The larvae are grasped, pressed against the extruder housing, heated to 220°C, by means of a planetary roller shaft, and kneaded. The resulting water vapor is extracted through the different zones of the extruder, and the temperatures are adjusted to decrease. The time and temperature were adjusted to achieve an initial moisture content of approximately 14%. An outlet tool can be inserted at the end of the extruder to adjust the consistency and extruder pressure.This process can produce granules or, without the need for a mold, a powder. By connecting a strand cooling system, the final product is even cooled during granulation.

[0093] Additional raw materials can also be added as an ingredient at the end or in the middle of a recipe in order to produce a feed or finished product.

[0094] Result / properties of the product obtained:

[0095] Color: light beige, light brown

[0096] Smell: Chocolate, Coconut

[0097] Taste: pleasant, slightly sour Protein content 47% in dry matter Amino acid composition: unchanged from the raw larva Moisture content: 14% Oil content: 20% in dry matter Consistency: powder or granules

[0098] Both trial products can now also be deoiled to obtain a deoiled protein concentrate with at least 50% protein content and improved odor, taste, hygiene, shelf life and color and increased amino acid content.

[0099] In a third experiment, raw larvae were washed with a water content of 68% and mechanically dewatered using a Flottweg Trikanter centrifuge at 80°C. The resulting press water was separated into oil and water using a disc separator. The water was drained off, and the oil was examined separately.

[0100] The dry material, with a water content of approximately 40% (w / w), was dried in an Entex planetary roller extruder (TP / WE 70 / 800 M2 RG) at 380°C for an effective drying time of 20 seconds. The larvae are fed into an extruder using planetary shaft technology via a metering device. This extruder contains a rotating rotor whose speed can be controlled by a frequency converter to regulate the throughput time. The larvae are captured, pressed against the extruder housing, heated to 380°C, by means of a planetary roller shaft, and kneaded. The resulting water vapor is extracted through the different zones of the extruder, and the temperatures are adjusted to decrease. The time and temperature were adjusted to achieve an initial moisture content of approximately 10% (w / w).

[0101] The dried powder was then processed together with starch and a vitamin-mineral premix in a single-screw extruder from AmandusKahl (OEE8) to form 3 mm and optionally 6 mm thick granules.

[0102] By connecting a moving floor or belt cooler, the final product was cooled during granulation and rendered abrasion-resistant. This prevents dust formation during storage and transport and also ensures good shelf life, good flow properties, and improved feed intake by the animal. Additional raw materials can also be added as ingredients in a recipe at the end of the process or into the planetary roller extruder, or later into the single-screw extruder, to produce a feed or finished product. Result / Properties of the resulting product: Color: beige / brown Odor: chocolate

[0103] Taste: pleasant, sweet

[0104] Protein content 67% (w / w) in dry matter - Amino acid composition: unchanged from raw larvae

[0105] Moisture content: 10% (w / w) Oil content: 8% (w / w) in dry matter Consistency: Powder or granules

Claims

Claims 1 . A process for producing an insect powder or granules, comprising the step of heat-treating insect larvae at a temperature of 200°C to 400°C for a period of 10 minutes or less and 10 seconds or more, thereby simultaneously drying and pasteurizing the insect larvae.

2. Method according to claim 1, comprising the steps: (a) Providing insect larvae, (b) heat-treating the insect larvae provided in step (a) at a temperature of 200°C to 400°C for a period of 10 minutes or less and 10 seconds or more, thereby simultaneously drying and pasteurising the insect larvae, and (c) grinding or granulating the heat-treated insect larvae obtained in step (b).

3. A process according to claim 1 or claim 2, wherein the heat treatment in step (b) is carried out at a temperature and for a duration which results in a residual moisture content of the insect larvae of 20% (w / w) or less.

4. A process according to any one of claims 1 to 3, wherein the heat treatment in step (b) is carried out at a temperature of 220°C to 360°C.

5. The method according to any one of claims 1 to 4, wherein the heat treatment in step (b) is carried out for a duration of 6 minutes or less and 10 seconds or more, 4 minutes or less and 10 seconds or more, 3 minutes or less and 10 seconds or more, 2 minutes or less and 10 seconds or more, or 1 minute or less and 10 seconds or more.

6. The process according to any one of claims 1 to 5, wherein the heat treatment in step (b) is carried out by means of a planetary roller extruder, a thin-film dryer, a multi-screw extruder, a twin-screw extruder, a single-screw extruder, a mill dryer, a disk dryer, a tube dryer, a drum dryer, a fluidized-bed dryer, a belt dryer, a microwave disk dryer, or a fluidized-bed dryer.

7. A method according to any one of claims 1 to 6, wherein the insect larvae are continuously moved during the heat treatment in step (b).

8. The method according to any one of claims 1 to 7, further comprising the step of mechanically reducing water by means of an oil press, centrifuge, filter press, screw press and / or a decanter before step (b).

9. A process according to any one of claims 1 to 8, further comprising the step of deoiling the resulting insect powder or granules after step (c).

10. The method according to any one of claims 1 to 9, wherein an insect powder obtained has an average particle size of 500 pm or less and wherein an insect granulate obtained has an average particle size of more than 500 pm.

11. A process according to any one of claims 1 to 10, wherein the insect powder or granulate obtained (i) less than 10 CFU / g (colony forming units per gram) of Clostridium perfringens, (ii) less than 100 CFU / g Enterobactericeae sp., (iii) no detectable salmonella (Salmonella sp.), (iv) no detectable pesticides, (v) no detectable viruses, (vi) less than 0.15 mg / kg lead, (vii) less than 0.05 mg / kg cadmium, and / or (viii) contains less than 0.05 mg / kg of mercury.

12. The method according to any one of claims 1 to 11, wherein the insect larvae are selected from the group consisting of fly larvae (Brachycera), larvae of stored product pests, cricket larvae (Grylloidae) and mixtures thereof.

13. The method according to claim 12, wherein the insect larvae are selected from the group consisting of larvae of the black soldier fly (Hermetia illucens), larvae of the flour beetle (Tenebrio molitor), larvae of the flour beetle (Tribolium castaneum), larvae of the house cricket (Acheta domesticus) and mixtures thereof.

14. Insect powder or granules obtained by the process according to any one of claims 1 to 13.

15. Food or feed containing the insect powder or granules according to claim 14.

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