EP4138551A1

EP4138551A1 - Method and system for rearing insects

Info

Publication number: EP4138551A1
Application number: EP20729117.0A
Authority: EP
Inventors: Johannes Nikola; Johannes Erkkonen; Tiiu KYLLÖNEN
Original assignee: Entocube Oy
Current assignee: Ec Holding Oy
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2023-03-01
Also published as: JP7565099B2; JP2023529271A; WO2021214375A1

Abstract

The present disclosure describes a method and a system for rearing insects. In the method and the system, edible insects, and in particular crickets, can be reared in a rearing container or containers. The container comprises a rearing matrix that has been formed from a long sheet of ductile material that has been folded on top5of itself into a plurality of overlapping layers on a rack. The layers form a plurality of overlapping, drooping loops. The sheet has been perforated with a pattern of cuts through the sheet.

Description

METHOD AND SYSTEM FOR REARING INSECTS FIELD

The invention relates to rearing of edible insects, and in particular, rearing of crickets in a rearing container. BACKGROUND INFORMATION

While the eggs, larvae, pupae, and adults of certain insects have been eaten by humans from prehistoric times to the present day, rearing of such insects for commercial consumption is relatively new, at least in larger scale. The rearing processes still typically rely heavily on manual labour. For example, feed and water may still be manually supplied. Further, the rearing environment may be manually prepared for each harvest. For example, a habitat for insects may be manually assembled out of egg cartons for each new batch of insects. A less labour-intensive but costlier approach is to use bottle dividers (cardboard matrices for holding a plurality bottles) as the habitat. Low-tech approaches may still be considered a viable option, at least where manual labour is more affordable. However, as demand for insect-based products increases, competitiveness of the rearing processes become increasingly relevant. At the same time, developing legislation and regulations related to insect rearing sets additional restrictions and quality standards for the rearing. These aspects set new requirements for improving the rearing processes.

As the industry develops, more automated approaches for rearing are becoming available. The scaling of these approaches into a large scale is not without problems. For example, it may be very challenging to maintain sufficient level of hygiene in an automated, large scale rearing process. Insufficient hygiene may lead to an increased risk of bacterial, fungal or viral contamination of the end product (insects used as food and feed) or rearing tools and devices. Further, monitoring and control of unwanted insect species and pests may be a difficult task in current large-scale rearing systems. In addition, non-optimal environmental parameters may lead to an increased death rate in the insect population or increase the cannibalistic behaviour of the insects. Solving these challenges may require costly technical implementations. Therefore, it may be difficult to make large-scale rearing economically feasible. BRIEF DISCLOSURE

An object of the present disclosure is to provide a method and a system for implementing the method so as to alleviate the above disadvantages. The object of the disclosure is achieved by a method and a system which are characterized by what is stated in the independent claims. The preferred embodiments of the disclosure are disclosed in the dependent claims.

In a rearing system according to the present disclosure, edible insects, and in particular crickets, may be reared in a rearing container or containers. The container preferably comprises a rearing matrix that has been formed from a long sheet of ductile material that has been folded on top of itself into a plurality of overlapping layers on a rack. The layers form a plurality of overlapping, drooping loops. The sheet has been perforated with a pattern of cuts through the sheet. This kind of rearing matrix provides several desirable features for insects. For example, it provides ease of movement and a large number of hiding places. Due to the structure of the rearing matrix, supplied feed migrates throughout the structure, thereby ensuring easier access to the feed. The rearing matrix sheet may be made of very inexpensive materials, such as cardboard. Further, the rearing matrix sheet may be extracted from the rearing container as a single, continuous sheet or ribbon. This enables easy automation of harvesting. The rearing matrix and the rearing container may be used together with an automatic feeding system that controls the amount and/or rate of feed supply. The automatic feeding system may control the feed supply in response to estimated size and age of the insect population and/or the temperature in which the insects are reared. Water consumption by the insect population may be used in estimating the population size, and this estimate may then be used by the automatic feeding. In this manner, the feeding process can be managed with reduced human interaction and risk of wasted feed due to overfeeding is lower. BRIEF DESCRIPTION OF THE DRAWINGS

In the following paragraphs, the invention will be described in greater detail by means of preferred embodiments with reference to the attached drawings, in which Figure la to le show simplified examples of a rearing matrix according to the present disclosure;

Figures 2a to 2c show an example of an insect-gathering arrangement according to the present disclosure;

Figure 3a to 3c shows an example of a separation arrangement according to the present disclosure;

Figure 4 shows an exemplary block diagram of a rearing system with automated feeding according to the present disclosure; and

Figure 5 shows simplified flow diagram of a method according to the present disclosure.

DETAILED DISCLOSURE

The present disclosure describes a rearing system for rearing edible insects. Arthropods, such as beetles, termites, ants, crickets and their different life stages are some examples of edible insects. Many species of crickets, locusts, beetles, wax moths and various other insects are also used as pet food and fish bait all over the world. Crickets are particularly relevant as a nutrient source for human consumption because of their protein content. Among the hundreds of different species of crickets, the house cricket [Acheta domesticus] is one of the most common species used for human consumption. In many parts of the world, crickets are consumed dried, baked or seasoned. Crickets are also farmed for animal feed for pets and agricultural livestock.

Insects typically require manual feeding (via distribution of fresh feed or dry granulated foods that may utilize resources originating from food industry side streams), watering, handling, harvesting, cleaning and aid in reproduction. The system according to the present disclosure may be used to provide all these aspects.

The system is especially well suited for rearing hemimetabolous, crawling insects in the order of Orthoptera (such as crickets, katydids and grasshoppers) and in the order of Blattodea (such as cockroaches). While the present disclosure discusses the rearing system mostly in relation to crickets, the system can be used for rearing other insects. Crickets are preferably housed in movable or stationary rearing containers or rearing areas in relatively high temperature (approximately 30°C) and furnished with a habitat structure to provide them shelter. The rearing system according to the present disclosure is scalable to industrial scale. The system can be used from a small-scale rearing unit (e.g. 0.1 - 1 m³ unit) to a large-scale rearing unit (e.g. 10 - 100 m³ unit). In the context of the present disclosure, a rearing unit may be a movable or stationary rearing container or a rearing area/space. A rearing system according to the present disclosure preferably comprises a rearing container. The size and shape of such container may vary depending on the application. Preferably the container is essentially box-shaped (rectangular cuboid), or at least has a rectangular top face. In this manner, a rearing matrix sheet according to the present disclosure can be folded into a neatly fitting rearing matrix inside the rearing container. The internal volume of the container may be in the range of 0.1 - 100 m³, for example. Preferably, the volume is in the range of 0.5 - 1 m³. Automation of rearing is simpler when the volume is in this range. Further, with volumes of this range, the scale of the rearing operation can be easily adjusted, e.g. by adding new containers. Length, width, and height of the container may be 0.25 - 5 m, for example. In the context of the present disclosure, "height" of the container is parallel to the direction of gravity during the use of the rearing container while "width" and "length" are perpendicular to "height". The dimensions "width" and "length" are perpendicular with respect to each other and define a horizontal plane. The rearing container maybe an open container or a closed container. The material of the rearing container is non-toxic for the insects but has such characteristics that it can withstand insect bites without breaking or fraying significantly. The material is preferably also easy to sanitize. The rearing container may be a plastic box with a detachable lid, for example. In a rearing system according to the present disclosure, the rearing container comprises a rearing matrix that acts as a habitat structure providing shelter for the insects. In the context of the present disclosure, the term "habitat structure" refers to a structure that is configured to act as a habitat for a population of edible insects. The insects live and grow in this habitat structure. The shape and construction of the habitat structure may have a significant effect on the functionality of the rearing system. Thus, an aspect of the rearing system is a rearing matrix according to the present disclosure. In the following paragraphs, the rearing matrix are discussed in relation to Figures la to le that show various exemplary features of the rearing matrix. In the context of the present disclosure, the rearing matrix is a habitat structure that comprises at least a rearing matrix sheet and a rearing matrix rack. The rack may be in the form of a horizontal ladder-like structure, for example. The rearing matrix sheet is intended to form a habitat surface for rearing insects, and the rearing matrix rack is intended to support the rearing matrix sheet. Figures la and lb show simplified examples of a rearing matrix according to the present disclosure. In Figure la, a perspective view of a rearing container 14 is shown. The two front facing sides of the container 14 are shown as transparent. The container 14 has a rearing matrix that comprises two rearing matrix sheets 10 arranged into two stacks 15 next to each other on spokes of a rearing matrix rack 12. Throughout the drawings of the present disclosure, a reference number is attached to only one element in a drawing when the drawing shows a plurality of the same element. Figure lb shows a simplified cross-sectional diagram of a rearing matrix according to the present disclosure. In Figures la and lb, rearing matrix sheets 10 is laid on top of spokes 12 of a rearing matrix rack. Together, the sheets 10 and the rack form a rearing matrix. The rearing matrix may be arranged inside a rearing container 14, for example. The rearing matrix rack may comprise a plurality of spokes arranged in a row. In some embodiments, the spokes are in a row on a horizontal plane. In Figures la and lb, five round spokes 12 are shown. They are arranged in a lengthwise row on a horizontal plane. The spokes 12 extend in widthwise direction (i.e. direction W in Figure la and the direction parallel to viewing direction of

Figure lb). The rearing matrix sheet (or sheets) 10 may be folded into a plurality of layers on the rearing matrix rack to form a plurality of overlapping, drooped folds, thereby forming the rearing matrix. In Figure 1 b, the rearing matrix sheet 10 is folded into six layers 102 on top of the spokes 12 of the rearing matrix rack. Portions 104 of the layers 102 between the spokes 12 are arranged to form drooped folds 106. The drooped folds 106 may be arranged such that they have different lengths. Upper drooped folds may be shorter than drooped folds below them. In this manner, gaps form between the drooped layers 106, as also shown in Figure lb. This provides versatility to the structure of the rearing matrix and increases the size of the habitat formed by the rearing matrix. The folding of the rearing matrix sheet 10 may be configured such that may be extracted from the rearing container 14 as a single, continuous, elongated sheet or ribbon. For example, as shown in Figure lb the sheet 10 may be laid on top spokes 12 of the rack in a back and forth manner from a first end 140 of the container 14 to a second end 142 of the container 14 so that end folds 108 form alternately on both of the ends 140 and 142 .

In Figures la and lb, the spokes 12 of the rearing matrix rack are arranged to a horizontal plane at a regular interval. However, other configurations are possible in a rearing matrix according to the present disclosure, as long as the configurations enable folding of the rearing matrix sheet into overlapping folds on top of the spokes. For example, the spokes may be at different intervals and/or they may be at different heights. Also, the number of spokes may differ based on the size of the rearing container and folding configuration. The rearing matrix rack may be adapted to support one rearing matrix sheet or a plurality of rearing matrix sheets in parallel on the spokes of the rack. While Figure la shows two separate rearing matrix sheets, one rearing matrix sheet may be used instead. For example, a long rearing matrix sheet may be arranged into a plurality of stacks of drooping folds on the rearing matrix rack. In Figure la, the two stacks 15 may also be made of a single rearing matrix sheet. Alternatively, a rearing matrix may be folded into staggered layers that overlap with each other only partially so that a spread stack formed by the staggered layers completely or mostly covers the spokes of the rearing matrix sheet. For example, in Figure la, a rearing matrix sheet may be arranged into partially overlapping, staggered layers so that they cover the whole width W of the rearing container 14 even when the width of the rearing matrix sheet itself is less than the width W of the rearing container 14.

The spokes preferably have smooth surface so as to minimize risk of tearing the rearing matrix sheet when it is being removed during harvest. Alternatively, or in addition, the spokes may be in the form of rolls that rotate freely when the rearing matrix is being removed. In some embodiments, the rearing matrix rack is a separate structure that can be inserted inside the rearing container. Alternatively, the rearing matrix rack may be integrated to the inside walls of the rearing container. Width of the rearing matrix sheet and the rearing matrix rack may be selected based on the width of the interior space of the rearing container. The width may be 40 to 150 cm, for example. Preferably, the width is 60 to 100 cm. A rearing matrix sheet according to the present disclosure may be in the form of an elongated sheet with a pattern of cuts through the sheet so that the sheet forms a grid-like structure. The cuts may be formed such that they provide insects access through the rearing matrix sheet. Figures lc to Id show exemplary details of a rearing matrix sheet according to the present disclosure. In Figure lc, a top view of a portion of a rearing matrix sheet 10 is shown. The sheet 10 has a plurality of cuts 101 through the sheet 10 from one side to the opposite side. In the context of the rearing matrix sheet, the term "elongated" is intended to be mean that the sheet may be rectangular with its length significantly larger than its width, e.g. the length of the sheet is at least 3 times, preferably at least 10 times, the width of the sheet. Length L of the rearing matrix sheet 10 is a dimension along which the rearing matrix sheet 10 is being pulled when the rearing matrix sheet 10 is gathered at the harvest of the insects. Width W of the rearing matrix sheet is a dimension that is perpendicular to the length L. The length and width extend along a plane parallel to the two sides of the sheet 10. Thickness of the sheet 10 is perpendicular the length L and the width W.

As mentioned above, a rearing matrix sheet according to the present disclosure may comprise a pattern of cuts extending through the sheet. Figure lc shows one preferable pattern for the cuts. In Figure lc, the cuts 101 are linear cuts aligned with the length L of the rearing matrix sheet 10 so as to ensure sufficient tensile strength of the matrix sheet 10 along the length L. The cuts 101 structure may form a regular, grid-like pattern, for example. Figure lc shows one preferable example of a suitable cut pattern. In Figure lc, the cuts 101 are arranged into a pattern of pairs of parallel cuts in staggered rows. The distance between the cuts in a pair may be in the range of 5 - 15 mm, for example. The pattern of Figure lc enables one preferable deformation of the otherwise flat surface topology of the two sides of the rearing matrix sheet 10. Figure Id shows a perspective view of this deformation. For simplicity, the rearing matrix sheet is visualized as a sheet without thickness in Figure Id. In Figure Id, pairs of cuts define bridges 16 into the sheet 10. The bridges may be in the form of straight strips that are separated from the rest from sheet 10 in their centre section 161 but are connected to the sheet by their ends 162. The bridges form openings to the rearing matrix sheet 10. These openings provide insects access through the rearing matrix 10.

In order to facilitate the folding of the rearing matrix sheet into the plurality of overlapping folds, the material and/or surface structure of the rearing matrix sheet is ductile. Further, when the material of the rearing matrix sheet is ductile, the sheet can be easily deformed to the form as shown in Figure Id. The sheet may be rectangular with its length significantly larger than its width. The rearing matrix sheet may be made of corrugated cardboard, for example. The corrugated cardboard may comprise a layer having small, wave-shaped, width-wise corrugations. Figure le shows a simplified, lengthwise cross section of the rearing matrix sheet 18 made of cardboard. The rearing matrix sheet structure of Figure le can be used in the embodiments of Figures la to Id, for example. In Figure le, the cardboard rearing matrix sheet 18 comprises a corrugated middle layer 181 and flat outer layers 182 on both sides of the middle layer 181. The middle layer 181 forms a wavelike form extending along the length of the sheet 18. Correspondingly, each corrugation (i.e. each peak and valley of a wave) of the cardboard extending along the width of the rearing matrix sheet 18. The size of the corrugations may be few millimetres (3 - 8 mm) in the direction of the thickness of the sheet 18, for example. The small corrugations in the surface of the cardboard provide further shelter for small insects (e.g. young crickets in their pinhead stage). A rearing matrix sheet made of corrugated cardboard is very cheap and can be easily disposed after use. Surface of corrugated cardboard is such that insects are able to climb it. Further, because of the orientation of the corrugations of the middle layer 181 in Figure le, the rearing matrix 18 has is much more ductile along its length than along its width. As a result, the rearing matrix sheet 18 can be easily folded on the spokes of a rearing matrix rack. At the same time, the sheet 18 is at least semirigid along its width, thereby easing its deployment and removal. Figure le also shows two larger wavelike structures 183 in the rearing matrix sheet 18. The wavelike structures 183 may be in the form of the bridges as described in relation to Figure Id. The pattern of cuts may be formed to the cardboard sheet with a machine. A long rearing matrix sheet made of corrugated cardboard can be stored rolled to a roll along its length or folded into a bundle before use.

The example of Figure le describes one embodiment of a rearing matrix sheet according to the present. However, the rearing matrix sheet may also have other kind of constructions or may be made other materials. For example, a rearing matrix sheet may be formed out of a cardboard that has a corrugated layer and a flat outer layer only on one side of the corrugated layer. Alternatively, the rearing matrix may be made of a single, flat carboard layer. Further, other materials than cardboard may be used. For example, polymer-based materials may be used in the rearing matrix sheet.

A rearing matrix according to the present disclosure provides many advantages. For example, the rearing matrix can be assembled very quickly. The rearing matrix sheet can be spread on the rearing matrix rack in the matter of few minutes (preparation of an egg carton -based habitat, for example, requires much more time). Further, when the rearing matrix sheet is in the form of a single, continuous sheet, insects can be harvested very quickly. A rearing matrix approach according to the present disclosure is also very cheap even in small-scale rearing systems and is also hygienic.

A rearing matrix according to the present disclosure also provides many preferable features for the insects, such as ease of movement, hiding, and feeding. Ease of movement is preferable at least when the reared insects are crickets. Young crickets in their pinhead stage may be 100 times smaller than harvest-ready crickets. The young cricket can easily lose their way or get stuck in their habitat. Thus, the easily accessible rearing matrix according to the present disclosure improves the survival rate of young crickets. Ease of finding cover may reduce cannibalism and variance in size. For example, when crickets shed their exoskeletons, they have to find shelter for their new exoskeletons are very soft for a couple of hours after shedding the old one. Crickets with soft exoskeletons are more at risk of falling victim to possible cannibalistic behavior of the other crickets. A matrix according to the present disclosure provides shelter for insect of many different sizes. The matrix can also provide the crickets with several different microclimates based on the crickets’ whereabouts within the matrix (close to a heat source, close to feed, etc). The rearing matrix can be configured such that feed traverses downwards through the cuts of the overlapping layers of the rearing matrix sheet due to gravity and movements of the insects. In this manner, the supplied feed is distributed on a wider area within the rearing matrix. As a result, the feed is better utilized by the insects. Further, control of the feed supply by dominant insect individuals becomes more difficult, thereby leading to more uniform size of insects at harvest. The exemplary embodiments of Figures la to le are just some examples of suitable structures, cut patterns, and materials. However, other structures, cut patterns and materials may also be used in a rearing matrix according to the present disclosure. Further, while the above examples mostly discuss rearing matrices formed on a rearing matrix rack, a rearing matrix according to the present disclosure can also be formed without a rearing matrix rack. A rearing matrix sheet according to the present disclosure may be folded into a rearing matrix on the bottom of a rearing container, for example. This rearing matrix may lack any drooped folds. While the drooped folds have the advantage of providing versatility to the structure of a rearing matrix according to the present disclosure, the rearing matrix can also be formed without them. A rearing matrix without the drooped folds has its own advantages. Without the drooped folds, the rearing matrix may be denser. It may have smaller openings and gaps than a rearing matrix with drooped folds and may thus be well suited for small and/or young insects. In some applications, insect nymphs may be first reared in a rearing matrix without drooped folds, and once they have reached a certain average size, they may be moved to a different rearing matrix (e.g. a rearing matrix with drooped folds).

Another aspect of a rearing system according to the present disclosure is ease of harvesting. For this reason, the present disclosure describes a sweeper device that can be used for removing insects from the rearing matrix of the rearing container. The present disclosure also describes an insect-gathering arrangement in the rearing container. Figures 2a to 2c show exemplary features of a sweeping device 22 and an insect-gathering arrangement 24 according to the present disclosure. Figure 2a shows an exemplary perspective view of the sweeper device and the insect-gathering arrangement Figure 2b shows a simplified, lengthwise cross- sectional diagram of the sweeper 22 and the insect-gathering arrangement 24. Figure 2c shows a perspective view of details of the insect-gathering arrangement 24.

A sweeping device according to the present disclosure may comprise at least two opposing rotating sweeper rolls with a plurality of flexible, elongated members (e.g. bristles, flaps, wings) extending from the surfaces of the rolls. Figures 2a and 2b show an embodiment where the sweeper device 22 comprises two sweeper rolls 221. The sweeper device 22 may be mounted on a detachable lid 222, for example. The lid 222 may be configured to fit on top of a rearing container according to the present disclosure so as to make the harvesting easier. In this manner, a sweeper device may be mounted on the rearing container In Figures 2a and 2b, the sweeper device 22 is mounted on a rearing container 14 according to the present disclosure. In Figure 2a and 2b, each roll 223 comprises two wings 223 positioned on opposite sides of the roll 221. The sweeper rolls 221 have a narrow slot 224 between each other. The sweeping device 22 is configured receive the rearing matrix sheet through the slot so that it passes between the sweeper rolls. Figure 2b shows a rearing matrix sheet 10 passing through the rolls 221. The sweeper rolls 221 are configured to repel and/or dislodge insects from the rearing matrix sheet while the rearing matrix sheet is conveyed between the sweeper rolls. For example, the rolls 221 may be configured to beat and shake the sheet 10 with the wings 223 (or other elongated members) to scare the insects and/or the rolls may be configured to brush insects off the sheet 10 by sweeping motion caused by their rotation. The insects are not able to get past the sweeper rolls 221 and they fall down to the bottom of the rearing container. Rotation of the sweeper rolls 221 may be driven by an electric motor assembly, for example. The electric motor assembly (not shown in Figure 2a to 2c) may be mounted on the lid 222, for example.

As shown in Figures 2a and 2b, the sweeper device 22 may further comprise a frame 225 with a support spoke 226 on top of the sweeper rolls 221. In Figures 2a and 2b, the frame is made of a transparent plastic. The centre axis of the support spoke 226 may be aligned to be parallel with the axes of the sweeper rolls 221 and the support spoke may be positioned above the gap between the sweeper rolls so that the pulling force pulling the rearing matrix sheet 10 an upwards through the sweeper rolls 221 is transformed from a up-pointing pulling force into a horizontal pulling force. In this manner, it is easier for a person to pull the rearing matrix sheet. Alternatively, or in addition, once a first end of the rearing matrix sheet 10 has been fed to the sweeper device, the sweeping operation may continue automatically. In some embodiments, the sweeper device may comprise a traction device (such as a nip roller) for pulling the whole rearing matrix sheet from the rack steadily as a single, continuous ribbon. This way the insects can be quickly harvested in a reliable manner. Further, the insects can be removed from the rearing matrix sheet with less dust (compared with removal of insects by shaking the sheet, for example). As mentioned above, the rearing container may also be equipped with an insect gathering arrangement according to the present disclosure. One major function of the insect-gathering arrangement is improving ease of gathering insects from the bottom of the rearing container during and after the clearing of the rearing matrix sheet. For this purpose, the insect-gathering arrangement may comprise at least one suction inlet. In this context, a suction inlet is an entry point through which insects may be sucked out from the container to a suction line. Figures 2a to 2c show an example of an insect-gathering arrangement according to the present disclosure. In Figures 2a to 2c, a detachable the insect-gathering arrangement 24 is positioned at an inside wall of the rearing container 14. Figure 2a shows the portions of the insect-gathering arrangement 24 extending below the lid 22 with dashed lines.

The insect-gathering arrangement 24 in Figures 2a to 2c is a unit that comprises two parts: a suction inlet 242 and a dark cover 244. The suction inlet 242 (or, in some embodiments, inlets) may be positioned near the bottom of the container 14 so that the insects are able to easily access it. For example, the centre of the suction inlet 242 may be located on an internal wall of the rearing container 14 at the height of 15 cm or less from the bottom surface of the container 14. The suction inlet 242 may be at least partially covered with a dark-coloured cover 244 so as to give the insects an impression that the suction inlet 242 is a safe retreat. In Figures 2a to 2c, the cover 244 is fixed to the suction inlet 242 and has an L-shaped profile. Thus, the cover 244 may act as a stand for the unit formed by the inlet 242 and the cover 244, and the unit can be easily positioned on the bottom of the rearing container 14 at a sidewall of the container 14 without the unit falling down. When the insects have been scared off and/or forcibly removed from the rearing matrix 10 by using the sweeper device 22, for example, they instinctively seek for shelter. The dark-coloured cover 244 gives the neighbourhood of the suction inlet 242 an appearance of such shelter so the insects rush for it and enter the suction inlet. Once the insects enter the inlet 242 (or come close enough), the suction pulls the insects in the suction line.

The insect-gathering arrangement 24 as described in Figures 2a to 2c may be adapted to be a detachable unit so that it is used only during harvest. In this manner, the insect-gathering arrangement 24 may be inserted to a rearing container that is intended to be harvested next. Thus, only one device producing suction may be needed at a time (without a need for a more complex suction line network). As shown in Figures 2a and 2b, the lid 222 of the sweeper device 22 may comprise a slot sot that the sweeper device and the insect-gathering arrangement 24 can be used at the same time during harvest.

Since only live insects actively move towards the inlet, the above-discussed embodiment has the advantage that, in addition to being a means for gathering the insects, it also effectively acts as a first stage of separation between live and dead insects. Separation between live insects and dead insects is typically important, at least when the insects are intended for human consumption. The detachable embodiment of the insect-gathering arrangement shown in Figures 2a to 2c is just one example of possible implementations. Alternatively, the suction inlet (with a cover) may be integrated to an inside wall of the rearing container.

A rearing system according to the present disclosure may further comprise a separation arrangement. The separation arrangement may comprise a separation space to which at least one suction line sucks insects, and a separation surface below the separation space. The separation space is used to separate insects from the airflow of the suction line. The insects fall from the separation space to the separation surface below. Figures 3a to 3c show simplified examples of a separation arrangement. In Figure 3a, two chambers 32 and 34 are arranged on top of each other. Both chambers 32 and 34 have conical cross sections, thereby forming two down-pointing funnels in a stack. These funnels may be circular funnels or rectangular funnels, for example. The path of the insects is shown as arrows with a dashed line in Figure 3a.

The upper chamber 32 acts as a separation space in the form of a cyclone chamber that separates the insects from the incoming airflow. The upper chamber has an insect inlet 322 and a suction outlet 324 at the top of the chamber 32, and an insect outlet 326 at the bottom of the chamber 32. The suction inlet 324 may be connected to a machine that generates suction, thereby lowering the air pressure inside the upper chamber 32. In some embodiments, this machine may be a vacuum cleaner, for example.

The lowered air pressure inside the upper chamber 32 causes a suction to the insect inlet 322. The insect inlet 322 may be connected to a rearing container according to the present disclosure. For example, the insect inlet 322 may be connected to a rearing container according to Figures 2a to 2c. The suction causes insects to be sucked from the rearing container and are carried towards the upper chamber 32 by airflow. The suction and the airflow may be selected such that, as the insects enter the upper chamber 32, they fall downwards (assisted by gravity) and are separated from the air flow. At the same time, lighter objects, such as dust and other small debris may be sucked into the suction inlet 324. Because of the conical cross section of the upper chamber 32, the insects slip into the insect outlet 326 of the upper chamber 32. The inside walls of the upper chamber may be manufactured or treated such that the insects are not able to cling to the walls. The insect outlet 326 of the upper chamber 32 is configured to lead to the lower chamber 34. The lower chamber 34 acts as a separation chamber. The lower chamber comprises a separation surface in the form of a separation tray 36 onto which the insects fall from the insect outlet of the upper chamber 32. The lower chamber 34 also comprises an outlet 344. The lower chamber 34 and the separation tray 36 may be configured such that insects and any remaining debris sucked in to the suction line from the bottom of the rearing container (such as uneaten feed and/or insect frass) fall to the separation tray 36 assisted by gravity. The separation tray 36 is configured such that live crickets are able to climb off it to fall to an outlet 344. In Figure 3a, the tray 36 comprises a planar structure 361 at the centre of the tray 36 and tubular structures 362 on both sides of the planar structure 361 at the periphery of the tray 36. An inner portion 364 of the top side of the tubular structures 362 may be configured or treated such that insects can climb it while an outer portion 366 of the top side of the tubular structures 362 may be configured or treated such that the outer portion is slippery and the insects fall off it. The instinct to seek shelter and the proximity of other insects falling on the tray 36 drive live insects from the tray 36 so that only dead insects remain on the tray 36. Additionally, the separation tray 36 may configured such that the possible debris falls through a sifter grid into a reservoir and remains in the reservoir. This provides a second stage of separation. In Figure 3a, the planar structure may be a sift, and a reservoir 368 is positioned below it. Figure 3b shows a perspective view of the tray 36 in the lower chamber 34 (with the front-facing side of the chamber cut off). In Figure 3b, the two tubular structures 362 are on both sides of a sift 361. On their top side, both tubular structures have an inner portion 364 that the insects can climb and an outer portion that is slippery for the insects. Figure 3b also show a reservoir 368 into which debris fall through the sift 361. In some embodiments, the whole separation tray (with the reservoir) may be removed from the lower chamber for cleaning. Alternatively, the sift may detachable from the tray. For example, the lower chamber may be provided with a horizontal slit through which a planar sift can be removed and installed back. In this manner, the tray 36 can be cleaned without removing the whole tray. The outlet 344 of the lower chamber 34 may lead to a unit that freezes and/or other unit that further processes the insects. While Figure 3b shows a separation chamber with a rectangular conical shape, the chambers of separation arrangements according to the present disclosure are not limited to such shapes. For example, in some embodiments, the chambers may also have a circular conical shape. In some embodiments, instead of a reservoir, the lower chamber may comprise a second conical shape forming another funnel inside the funnel shape of the lower chamber. Figure 3c shows an embodiment where a funnel-shaped lower chamber 35 comprises a second, inner funnel 378 positioned directly below a separation tray 37. The debris passing through the sift 371 of the separation tray 37 fall in the mouth of the inner funnel 378. The inner funnel 378 may lead debris falling through the sift to a larger reservoir, for example. Similar to the embodiment of Figure 3a, insects are able to climb over the tubular structure 372 of the separation tray 37 in Figure 3c. As they climb over the tubular structures 372, they fall to an outlet 354 surrounding the inner funnel 378.

In addition to the structure and features of a rearing habitat, the amount of feed and water has a significant effect on the growth rate of an insect population reared in the environment. If the insects are not provided with enough feed, their population is not able to grow at an optimal rate. At the same time, an oversupply of feed may lead to feed waste and hygiene problems. Therefore, it is preferable to control the amount of feed available in the rearing container based on the actual feed consumption. Thus, yet another aspect of a rearing system according to the present disclosure is automatic feeding. For this purpose, a rearing system according to the present disclosure may further comprise a liquid dispenser configured to supply liquid to insects in the rearing container and an automatic feed dispenser configured to supply feed to the insects in the rearing container. In addition, the system may comprise a control system configured to control automatic feed dispenser. The amount of feed (or the rate of feeding) may be controlled in response to an estimate of the size of the insect population inside the rearing container. The estimate of the size of the insect population may be based on gathered historical data, for example. A model of (the growth cycles of) an insect population in its different growth stages may be formed, and the control system may be configured to adapt the amount and/or rate of feed supplied to the insects based on this model. Water consumption may be used for providing a reliable feedback on the size of the insect population. Thus, the system may further comprise a sensor for sensing liquid consumption from the liquid dispenser, and the control system is configured to control the amount of supplied feed based on the sensed liquid consumption. Figure 4 shows an exemplary block diagram of a rearing system with automated feeding according to the present disclosure. In Figure 4, the rearing system comprises a rearing container 42 according to the present disclosure (e.g. as shown in Figures la, lb, 2a, and 2b), a water dispenser 44 for providing water to insects inside the container 42 and a feed dispenser 46 for providing feed to the insect. The water dispenser 44 comprises a sensor 441 measuring consumption of water provided by the water dispenser 44. The feed dispenser 46 comprises an adjustment unit 462 (e.g. an electrically controlled valve) that controls the size of feed portions and/or the rate at which the portions are released in response to a control signal. The rearing system further comprises a controller 48 that receives measurement data from the sensor 441 as an input. The controller 48 may then determine an appropriate amount/rate for the supplied feed based on the measurement data and generate a control signal controlling the adjustment unit 862 based on the determined appropriate feed amount/rate.

The appropriate amount may be determined in various ways. In some embodiments, the sensed liquid consumption may be used together with the model of insect population in forming an accurate estimate of the current size of the insect population. The amount of supplied feed (or the rate of supplying feed) may then be adapted based on this estimate. In some embodiments, the system may also utilize other datasets, such as temperature measurements and/or ventilation rate, in the estimation of the size of the insect population. Alternatively, in some embodiments, the amount of feed or the supply rate may simply be directly adapted based on the sensed water consumption. The water consumption and/or the estimated population may also be used for monitoring purposes. For example, if the water consumption or the estimated population suddenly drops or otherwise deviates from the expected values, an alarm may be raised so that personnel become aware of the issue. In the following paragraphs, two exemplary embodiments of a rearing system according to the present disclosure are presented. In a first embodiment, the rearing habitat is in the form of an open-climate rearing container. The phrase "open-climate rearing container" is intended to be understood as a rearing container that does not have its own, independently controllable climate. The container may be similar or the same as shown in Figures la and lb, for example. A plurality of containers may be arranged in rows. Feed may be supplied to the rearing container (or containers) manually or with a moving dispenser robot, for example. Water may be provided with a central watering system or each rearing container may be provided with its own, independently controllable water dispenser. In the latter option, the water dispenser may be provided with a water consumption sensor so as to provide feedback on the size of the insect population. This feedback may be utilized in adjusting the feeding and/or in monitoring the progress of the rearing process, e.g. as discussed in relation to automatic feeding above. As the rearing containers are open-climate containers, the climate inside each rearing container changes along with the ambient climate. In order to optimize the climate parameters for optimal rearing, the rearing container may be located inside a climate-controlled facility. This kind of approach may be preferable when manual labour is affordable and/or if positioning the rearing container/containers in a climate-controlled facility is economically reasonable.

In a second embodiment of a rearing system according to the present disclosure, a closed-climate rearing container is used. In this context, the phrase "closed-climate rearing container" is intended to be understood as a rearing container that has its own, independently controllable climate. In order to achieve this, the inside volume of the rearing container is sealed off from the ambient climate (with a lid, for example). The rearing system may comprise at least one rearing container with a rearing matrix. The rearing container and the rearing matrix may be the similar or the same as described in the first embodiment (and in Figures la and lb), for example. The rearing container is provided with an automatic feed dispenser and a water dispenser. Preferably, the rearing system comprises a plurality of such rearing containers. The rearing container in the second embodiment may be provided with a climate control arrangement that controls at least one climate parameter (such as temperature and/or humidity) inside the rearing container. The climate control may comprise a ventilation inlet and outlet in the walls of the rearing container. The climate control may further comprise a heater inside the container or the air entering the rearing container may be heated outside the container. The rearing system in the second embodiment can be configured such that each rearing container is a separate, stand-alone unit. The rearing containers may be configured to a compact, stackable form, and the machinery required for maintaining the rearing process may be optimized for the intended size of population in the container.

Because each rearing container comprises all machinery for maintaining the rearing process in the container, it is also possible to adjust the capacity of the rearing process as the number of rearing containers in use can be easily reduced or increased. It is also possible to control the rearing process in each rearing container individually. As the insects in different rearing containers are separated from each other, it is easier to maintain overall hygiene and prevent diseases or pests from spreading.

In addition, since the climate inside the rearing container can be different from the ambient climate, the climate outside the rearing container can be adjusted to a level more tolerable for human personnel. For example, in cricket rearing, the personnel do not have to tolerate the relatively high temperature of 32°C preferred in cricket rearing. Further, with the isolation, exposure of personnel to dust and other particles originating from the insect habitat can be minimized. In this manner, risk of developing allergic reactions (e.g. due to long-time exposure) can be minimized.

While the above paragraphs discuss automatic feeding in relation to rearing in a rearing container, the automatic feeding according to the present disclosure can be applied to other kinds of rearing environments, such as large rearing spaces and areas in large facilities. Further, while the above paragraphs discuss estimation of population size in relation to automatic feeding, the estimate of population size can be used in optimization of other variables in a rearing system. In addition, while the above-discussed feeding systems are mostly discussed in relation to the rearing matrix according to the present disclosure, the feeding system may also be used together with other kind of habitat structures, including the conventional egg carton -based and bottle divider -based structures. Yet another aspect that may play a significant role in optimising a rearing process of insects is breeding (i.e. egg-laying, incubation, hatching). For example, crickets breed relatively easily by tenfold per generation. In good conditions, they may breed by 50-fold, and in an optimal environment, they are able to breed by 200- fold per generation. However, consistency of the breeding and good quality of the offspring also play a significant role in a successful rearing process. In a rearing system according to the present disclosure, the breeding may be done in a separate unit. This unit may be a climate-controlled version of a rearing container according to the present disclosure, e.g. as discussed in relation to the second embodiment of a rearing system according to the present disclosure above. In this manner, the environmental parameters may be controlled to levels that are for incubation and hatching. For example, humidity may preferably be held at a high level during incubation and hatching in order to achieve best results. Further, since the incubation/hatching units are separate, it is easier to control the amount of undesirable invasive insect species (e.g. flies and spiders) and other pests. Nymphs hatched from the eggs may be set in a rearing container and the rearing process may then begin. A portion (e.g. 2 - 10 %) of the nymphs may be used for breeding a new generation of eggs.

In order to maximise the number of new larvae, the insects may be provided a specifically dedicated breeding habitat. Coconut fibre and moss are some conventionally materials used as the breeding habitat. As these materials are natural materials, they bring in their own biological challenges to the breeding process. For example, each natural material may carry their own microbes. Further, finding eggs in these materials and separating the eggs from the material may be very challenging. Thus, the present disclosure also describes a breeding habitat according to the present disclosure. The breeding habitat comprises a microfiber cloth on which the insects may lay their eggs. Preferably, the microfiber cloth is a microfiber chenille cloth. The microfiber chenille cloth may be in the form of a large number of nodules of tubular appearance microfiber structures extending from the cloth surface. The structures may be around 2 - 5 cm long, for example. The chenille cloth provides a favourable habitat for egg-laying. The eggs are visible on the cloth and their number can be easily estimated. Further, the eggs can be easily detached from the cloth. When it is time to harvest the eggs, the cloth may be immersed in a liquid (e.g. water) in a container, causing the nodules to expand. As a result, the eggs fall off the nodules and drift to the bottom of the container. Unlike natural materials, very little other material than the eggs detach from the microfiber cloth. After gathering of the eggs, the cloth may be sanitized or sterilized and reused. The above-described breeding habitat according to the present disclosure provides a very quick and clean way for separating the eggs from the breeding habitat. The breeding habitat is especially well suited for crickets.

The present disclosure also describes a rearing method utilizing the above- discussed aspects of a rearing system according to the present disclosure. The rearing method is particularly suitable for rearing edible crickets. Figure 5 shows simplified flow diagram of the method. The method can be divided into four main stages: propagation, rearing, and harvest, and post-processing. In Figure 5, these stages are shown as sections 50, 52, 54, and 56. The first stage 50 may comprise steps related to egg-laying, incubating eggs, and hatching. In Figure 5, these aspects are covered in steps 502, 504, and 506. For example, in order to prepare new young insects for rearing, a method according to the present disclosure may comprise providing a micro-fibre cloth as an egg-laying surface, as discussed in earlier paragraphs of the present disclosure.

In the second stage 52 in Figure 5, the insects are reared for harvesting. The second stage 52 may also comprise steps related to preparing the rearing habitat. In Figure 5, this is shown as step 522. A rearing matrix according to the present disclosure is preferably used in the second stage 52. The rearing matrix is preferably in a rearing container according to the present disclosure. As discussed in the earlier paragraphs, the rearing matrix sheet may be an elongated sheet with a pattern of cuts through the elongated sheet so that the elongated sheet forms a grid-like structure. The method may then comprise folding the rearing matrix sheet on top of itself of a rearing matrix rack to form a plurality of overlapping, drooped folds. The rearing matrix rack may comprise a plurality of parallel spokes arranged in a row on a horizontal plane, as discussed in earlier paragraphs.

The second stage 52 may further comprise supplying liquid to insects in the rearing container with a liquid dispenser, sensing liquid consumption from the liquid dispenser, and supplying feed to the insects in the rearing container with an automatic feed dispenser. As discussed in earlier paragraphs, the amount of supplied feed may be based on the sensed liquid consumption. The control of the feed and water supply is shown as step 524 in Figure 5. The water consumption may be used for estimating the size of the insect population and the amount of feed supplied may be based on this estimate, for example. Further, as discussed earlier, the water consumption may also be used for monitoring purposes. The monitoring is shown as step 526 in Figure 5. As shown in Figure 5, the second stage 5 may also comprise a step 528 of controlling the climate inside of the rearing container.

Once the insects have reached a sufficiently large size, the method may move to its third stage 54 and the insects are harvested. For example, the third stage 54 of the method may comprise removing insects from the rearing matrix of the rearing container with a sweeping device. Figure 5 shows a step 542 of sweeping the insect in stage 54. As discussed earlier, the sweeper device may comprise at least two opposing rotating brushes configured to receive the rearing matrix between them and to repel and/or dislodge insects from the rearing matrix while the rearing matrix is conveyed between the brushes. As a result, the insects fall to the bottom of the rearing container. As discussed earlier, the rearing container may be provided with an inlet of the suction line inlet is at least partially covered with a dark-coloured cover. This cover gives the insects an impression that the pipe inlet is a safe retreat. The insects approaching the inlet may then be sucked from the rearing container to a separation chamber with a suction line. This part of the procedure is shown as step 544 in Figure 5. The separation chamber may define a separation space to which the insects are sucked and a separation surface below the separation space. The separation space and the separation tray may be configured such that insects fall to the separation surface assisted by gravity, and the separation tray being configured such that live crickets are able to climb off it to fall to an outlet.

From the outlet, insects may be transferred to further processing and/or freezing, for example. In Figure 5, this is shown as steps 562 and 564 of the fourth stage 56. However, a portion of the harvested insects may be used of reproduction. Thus, Figure 5 shows a returning flow path from the step 844 in the end of the third stage 54 back to the start of the first stage 50. While the present disclosure discusses rearing of insects mainly in relation crickets, methods and systems according to the present disclosure may be used for rearing other kinds of edible insects. It is obvious to a person skilled in the art that the method and the system can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1. A rearing matrix for rearing insects, wherein the rearing matrix comprises

- a rearing matrix sheet for forming a habitat surface for rearing insects, wherein the rearing matrix sheet is an elongated sheet with a pattern of cuts through the sheet so that the sheet forms a grid-like structure, and

- a rearing matrix rack with a plurality of parallel spokes, wherein the rearing matrix sheet has been folded on top of itself on the spokes of the rearing matrix rack to form a plurality of overlapping, drooped folds.

2. A rearing system comprising

- a rearing container for rearing insects therein, wherein the rearing container comprises a rearing matrix according to claim 1.

3. A rearing system according to claim 2, wherein the rearing system further comprises a sweeper device for removing insects from the rearing matrix sheet, wherein the sweeping device comprises

- at least two opposing sweeper rolls configured receive the rearing matrix sheet therebetween and to repel and/or dislodge insects from the rearing matrix while the rearing matrix is conveyed between the brushes.

4. A rearing system according to claim 2 or 3, wherein the rearing container is equipped with at least one suction inlet inside of the rearing container, the suction inlet being connectable to a suction line.

5. A rearing system according to claim 4, wherein the suction inlet is at least partially covered with a dark-coloured cover so as to give the insects an impression that the pipe inlet is a safe retreat.

6. A rearing system according to claim 4 or 5, wherein the rearing system further comprises a separation arrangement with a separation space and a separation surface below the separation space, wherein

- the separation space is configured to receive insects carried by air flow from the suction line and separate the insects from the air flow so that insects fall to the separation surface,

- the separation surface is configured such that live crickets are able to climb off it to fall to an outlet.

7. A rearing system according to any one of preceding claims, wherein the rearing system further comprises - a liquid dispenser configured to supply liquid to insects in the rearing container,

- a sensor for sensing liquid consumption from the liquid dispenser,

- an automatic feed dispenser configured to supply feed to the insects in the rearing container, and

- a control system configured to control automatic feed dispenser, wherein the control system is configured to control the amount of supplied feed based on the sensed liquid consumption.

8. A method for rearing insects, wherein the method comprises

- providing a rearing container with a rearing matrix sheet and a rearing matrix rack, wherein the rearing matrix sheet is an elongated sheet with a pattern of cuts through the sheet so that the sheet forms a grid-like structure, and the rearing matrix rack has a plurality of parallel pokes,

- folding portions of the rearing matrix sheet on top of itself on the spokes of the rearing matrix rack to form a plurality of overlapping, drooped folds.

9. A method according to claim 8, wherein the method further comprises

- removing insects from the rearing matrix of the rearing container with a sweeping device that comprises at least two opposing sweeper rolls configured receive the rearing matrix therebetween and to repel and/or dislodge insects from the rearing matrix while the rearing matrix is conveyed between the brushes.

10. A method according to claim 8 or 9, wherein the method comprises

- providing the rearing container with a suction inlet of a suction line, wherein the suction inlet is at least partially covered with a dark-coloured cover so as to give the insects an impression that the pipe inlet is a safe retreat.

11. A method according to any one of claims 8 to 10, wherein the method further comprises

- supplying liquid to insects in the rearing container with a liquid dispenser, - sensing liquid consumption from the liquid dispenser, and

- supplying feed to the insects in the rearing container with an automatic feed dispenser, wherein the amount of supplied feed based on the sensed liquid consumption.