Improved method for enriching processed beetle larvae with vitamin D3 by ultraviolet treatment and related food powders

Abstract

The present invention relates to a method for the preparation of beetle powder, which comprises a phototreatment step during which at least one light source radiates ultraviolet light of the UVB type in the direction of the processed beetle larvae, said ultraviolet light of the UVB type reaching a concentration of 80 μW / cm2 in the powder. 2 It has an irradiance of more than 10 ...

Description

[Technical field]

[0001] The present invention relates to the field of the food industry.

[0002] The object of the invention more precisely concerns the production of a food powder containing beetles.

[0003] One of the aims of the present invention is to improve the enrichment with vitamin D3 of powder derived from beetle larvae.

[0004] The present invention therefore has numerous applications, especially in the food industry and especially for human food, reptile feed, animal feed (pet food / pet care / nutraceuticals) or fish farming. [Background technology]

[0005] Vitamin D3 has important properties for the body.

[0006] Vitamin D3 as used herein means cholecalciferol.

[0007] In humans, vitamin D3 is involved, among other things, in maintaining normal blood levels of calcium and phosphorus that is absorbed in the intestine. It strengthens the immune system and improves cognitive function.

[0008] Vitamin D3 also plays an essential role in maintaining bones and skeletal muscles in humans and pets, such as dogs.

[0009] Vitamin D3 is used, for example, in addition to calcium to prevent osteoporosis in elderly people.

[0010] In reptiles, vitamin D3 allows optimal assimilation of calcium and mineralization of bone.

[0011] Today, it is known that 50% of healthy adults suffer from vitamin D3 deficiency.

[0012] The daily requirement for vitamin D3 is 15 μg for adults and can rise to 20 μg for those over 70 years of age.

[0013] Traditionally, dietary sources of vitamin D3 are substantially derived from fish, particularly through fish oils, fillets and livers, but fish is a declining resource and is therefore becoming increasingly expensive.

[0014] Vitamin D3 extracted from boreal lichen or synthesized from lanolin can also be found in supplement form.

[0015] Thus, the amount of food rich in Vitamin D3 is decreasing. As far as the demand for Vitamin D3 is concerned, it is increasing exponentially.

[0016] Food industry players are therefore devoting a great deal of energy to finding solutions that will allow them to produce this vitamin D3 in a sustainable and rational way.

[0017] Patent document WO 2005 / 023964, belonging to the same applicant, is known as prior art, which proposes the production of a food powder rich in vitamin D3, which contains beetles.

[0018] In this document, more particularly, ultraviolet light treatment, so-called UV treatment, during the developmental stages of larvae of the Tenebrio molitor or Alphitobius diaperinus type is proposed, which allows a significant synthesis of vitamin D3.

[0019] Indeed, the results obtained with the enrichment technique proposed in patent document 1 reveal that without UV treatment the larvae contain little or no vitamin D3 (0-2 μg / 100 g dry weight), whereas with UV treatment during the larval development stage an average maximum concentration of vitamin D3 is obtained in the larvae of about 50 μg / 100 g dry weight on average. These live larvae enriched in vitamin D3 therefore make it possible to obtain, after a processing step, beetle powder or beetle larvae enriched in vitamin D3.

[0020] However, the Applicant argues that at an industrial level, the implementation of the solution proposed in US Pat. No. 5,399,633 remains complicated.

[0021] Indeed, according to the technical teachings of this document, the UV treatment is carried out directly on live larvae during these larval development stages.

[0022] This creates several problems that can significantly impair farm productivity and make the industrialization of UV treatment methods difficult.

[0023] Applicants allege, first, that UV treatment of live larvae can cause larval mortality that is 10 times greater than the larval mortality observed in larvae without UV treatment, particularly when the light source is positioned at a distance of 25 cm or less from the live larvae.

[0024] Indeed, tests have shown that 12-week-old larvae subjected to UV treatment (25 W lamp, UVB index 200) for 10 days at a distance of 25 cm from the light source had a mortality rate of 0.1%, compared to 0.01% without this light treatment.

[0025] Second, applicants argue that the surface area required to perform this type of UV treatment is substantial.

[0026] To synthesize 50 μg / 100 g of vitamin D3 in the dry weight of the larvae, a 25 W UVB lamp (UVB index 200) must be placed for 10 days at a distance of 25 cm from the tank in which the larvae are kept. The tank has a volume of 56 cm x 38 cm x 17 cm. This configuration allows to minimize mortality while maximizing the rate of vitamin D3 synthesis.

[0027] Therefore, in the above conditions, a 125cm x 200cm x 30cm structure can only produce 10.5 kilograms of live larvae (or 3.75 kilograms of powder) every 10 days, making it very costly both in terms of time and surface area.

[0028] Thus, the applicant claims that the prior art solutions are not fully satisfactory to date for the industrialization of the production of vitamin D3-enriched beetle food powder.It is of great interest to find a reliable industrial solution that allows to significantly increase the vitamin D3 concentration in processed beetle larvae while reducing production costs. [Prior art documents] [Patent documents]

[0029] [Patent Document 1] International Publication No. 2019 / 229332 Summary of the Invention [Problem to be solved by the invention]

[0030] The present invention aims to improve the above situation.

[0031] The present invention more particularly aims to overcome the various drawbacks mentioned above by proposing an efficient solution, easy to implement at industrial level, for significantly increasing the vitamin D3 concentration in beetle powder while limiting industrial costs. [Means for solving the problem]

[0032] The object of the present invention relates, according to a first aspect, to a method for producing a beetle powder enriched with vitamin D3, comprising a phototreatment step during which at least one light source radiates ultraviolet light of the UVB type in the direction of processed beetle larvae.

[0033] According to the invention, UVB type ultraviolet light has a density of 80 μW / cm2 in the powder. 2 It has an irradiance of more than 10 ...

[0034] Such an 80μW / cm 2 It has been observed that by irradiating UVB rays with an irradiance of 1000 nm or more, the duration of UV treatment can be significantly shortened and a remarkable increase in vitamin D3 concentration can be obtained.

[0035] This shortening of the irradiation time makes it possible to optimize the process, reducing its costs and facilitating its industrialization.

[0036] Preferably, the irradiance of the emitted UVB light is 80 to 1,000 μW / cm 2 Preferably, the irradiance of the emitted UVB light is between 150 and 250 μW / cm 2 Preferably, the irradiance of the emitted UVB light is between 170 and 200 μW / cm 2 It is between.

[0037] UV pre-treatment process (processing): By processed larvae is meant beetle larvae which have been subjected to at least an insecticidal treatment.

[0038] Advantageously, the method according to the invention comprises a step of processing the beetle larvae, including killing said larvae, prior to the light treatment step. Preferably, said processing step is carried out on the beetles in the larval stage.

[0039] According to a first option, this killing is carried out by cold treatment, which means, for example, exposing the beetle larvae to a temperature below 4° C. for a time of more than 10 minutes.

[0040] According to a second option, this processing step is carried out by high-temperature treatment, which means, for example, exposing the beetle larvae to temperatures above 40° C. for more than 15 seconds in water (blanching) or to heated air for more than 30 minutes.

[0041] In a particular embodiment, during the killing process, the larvae can be placed in water having a temperature between 50 and 120° C., preferably between 85 and 110° C., and even more preferably between 90 and 100° C. This is also called blanching.

[0042] Such blanching killing techniques have been shown to be efficient and are able to preserve the nutritional properties of the beetles and reduce the bacterial load of the larvae.

[0043] Preferably, this blanching is carried out for a blanching time between 30 seconds and 10 minutes, preferably between 1 and 5 minutes.

[0044] According to a third option, the killing step can also be carried out by exposing the beetle larvae to microwaves, for example for at least 10 seconds.

[0045] Advantageously, the processing step includes a dehydration (or cooking) step, after disinfection, aimed at obtaining a water activity of the powder of less than 0.7.

[0046] For this dehydration, a microwave treatment can be provided, which means exposing the beetle larvae to microwaves, for example for at least 10 seconds.

[0047] For this dehydration, or alternatively or in addition, it is also possible to subject the killed larvae to a heat treatment.

[0048] During this heat treatment of the larvae for dehydration, the killed larvae are therefore placed in an environment of 40 to 250°C, preferably 50 to 150°C, for a treatment time of preferably 1 hour to 24 hours, whereby the killed larvae - 2 to 15% moisture, more preferably 3 to 8% moisture, and / or Water activity (AW) less than -0.7 has.

[0049] Preferably, during heat treatment, the processed larvae are arranged in a thickness of between 1 and 100 millimeters, preferably between 5 and 15 millimeters.

[0050] Optionally, the processed larvae may be subjected to crushing and / or squeezing.

[0051] Preferably, the processing step involves grinding the larvae after killing to obtain beetle powder.

[0052] It is noted here that crushing the larvae after dehydration can improve the performance of vitamin D3 synthesis after UV treatment, however, this step after dehydration remains optional.

[0053] After dehydration and grinding, beetle powder is obtained.

[0054] Beetle powder is, for example, - Whole Tenebrio molitor larvae that have been dry heat processed and crushed; - or whole larvae of Alphitobius diaperinus that have been dry heat processed and crushed; - or a mixture of these two larvae species subjected to dry heat processing and crushing; or a fraction of whole Tenebrio molitor larvae previously subjected to crushing, followed by dry heat processing and crushing; - or a fraction of whole larvae of Alphitobius diaperinus previously subjected to pressing processing, followed by dry heat processing and grinding; - or a mixture of these two larval fractions previously subjected to a pressing process, followed by a dry heat process and grinding; This refers to dry powder (AW<0.7) consisting of either

[0055] In a particular embodiment, the processing step includes a first screening of the larvae to remove residues such as excrement or possible food residues. However, such screening is optional. It has the simple purpose of cleaning the larvae before killing them.

[0056] Preferably, the processing step involves fasting for 24 to 48 hours. Such fasting avoids the appearance of new excrement. Therefore, such fasting is optional in the context of the present invention.

[0057] Optionally, the fasting step is followed by a second screening.

[0058] Advantageously, the processing step includes stunning at low temperatures between -18°C and +4°C prior to killing.

[0059] Preferably, the stunning step at low temperature is carried out with a stunning time of 1 to 5 minutes. Killing can also be carried out without stunning. Such stunning is therefore optional in the context of the present invention.

[0060] UV treatment process (synthesis of vitamin D3): Advantageously, the ultraviolet light emitted by the at least one light source in the direction of the processed beetle larvae during the light treatment step has the following properties: - consisting of electromagnetic radiation of the UVB type and with a wavelength between 280 nm and 320 nm; and / or - UVA type and consists of electromagnetic radiation with wavelengths between 320nm and 400nm.

[0061] Preferably, it is contemplated that during the light treatment step at least one light source is positioned at a predetermined distance from the beetle larvae between about 1 and 100 cm, preferably between about 5 and 20 cm.

[0062] The intensity of the UV light source decreases with distance from the source. The amount of vitamin D3 synthesized depends on the amount of UVB received per unit time. Advantageously, the at least one light source has a radiant power of between 13 and 125 watts, preferably between 20 and 50 watts.

[0063] Advantageously, during the light treatment step, at least one light source is intended to radiate ultraviolet light in the direction of the processed beetle larvae, with a treatment range of between 10 seconds and 24 hours, preferably between 1 and 7 minutes, more preferably between 2 and 5 minutes, advantageously this treatment range being achieved continuously or cumulatively.

[0064] It will be appreciated that the 3 minute UV treatment can be carried out, for example, continuously for 3 minutes or by three successive periods of 1 minute each, spaced apart by rest periods of several minutes. Advantageously, it is intended that during all or part of the light treatment step the processed beetle larvae are maintained in an environment having a substantially constant temperature between 15 and 35°C, preferably between 22 and 26°C.

[0065] The synthesis of vitamin D3 is optimized in the presence of temperatures above 20°C.

[0066] An object of the present invention relates, according to a second aspect, to the beetle powder obtainable by implementing the manufacturing method described above.

[0067] The object of the present invention, according to a third aspect, relates to the use of the above-mentioned beetle powder in human or animal food. Preferably, the powder is used as an ingredient or food supplement. Other advantageous uses are possible, for example as food for reptiles or fish.

[0068] drawing Other characteristics and advantages of the present invention will become apparent from the following description, with reference to the attached FIGS. 1 to 4A-4D, which show exemplary, non-limiting embodiments thereof. [Brief description of the drawings]

[0069] [Figure 1] FIG. 1 is a graph showing vitamin D3 concentrations in several samples of beetle larvae subjected to UV light treatment for an exposure time of 8 hours. [Diagram 2] FIG. 2 is a graph showing the change in vitamin D3 concentration as a function of time in several samples of beetle larvae subjected to UV light treatment. [Diagram 3] FIG. 3 is a graph showing the change in vitamin D3 concentration over time for several different samples of beetle powder exposed to a UV light source having a particular UVB irradiance. [Figure 4A] FIG. 4A includes a graph illustrating a first exemplary embodiment of the change in oxidation index of beetle powder as a function of UVB treatment time and UVB irradiance level. [Figure 4B] FIG. 4B includes a graph showing a second exemplary embodiment of the change in oxidation index of beetle powder as a function of UVB treatment time and UVB irradiation level. [Figure 4C] FIG. 4C includes a graph depicting a third exemplary embodiment of the change in oxidation index of beetle powder as a function of UVB treatment time and UVB irradiation level. [Figure 4D] FIG. 4D includes a graph depicting a fourth exemplary embodiment of the change in oxidation index of beetle powder as a function of duration of UVB treatment and UVB irradiation level. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070] An exemplary embodiment of the production of vitamin D3 enriched beetle powder will now be described below with additional reference to Figures 1 through 4A-4D.

[0071] Just to be clear, the powder production described here aims to develop a technique to significantly increase the concentration of vitamin D3 in powders containing beetles, and in particular beetles of the Tenebrio molitor and / or Alphitobius diaperinus type. Contrary to the technique of applying UV treatment to live beetles (e.g. fresh beetle larvae), as proposed in US Pat. No. 5,999,593, one of the basic concepts of the present invention is to apply UV treatment to live beetles (e.g. fresh beetle larvae) at a dose of 80 μW / cm 2 The UV treatment comprises irradiating the treated larvae with UVB light having an irradiance of at least 100 nm.

[0072] By processed larvae is meant herein beetle larvae which have been at least subjected to killing.

[0073] In the examples described herein and used in the various experiments, larvae selected from the following species are used: Tenebrio molitor and / or Alphitobius diaperinus.

[0074] It is understood that other experiments not described here have been performed using other species and show comparable results.

[0075] It should be noted that the larval development stages are not described herein since the present invention relates to UV treatment (and incidentally processing steps) and pre-cultivation steps are not part of the present invention.

[0076] Processing steps: In a particular embodiment of the invention, the processing steps are carried out in the following manner.

[0077] Between the 6th and 14th week of growth, more preferably between the 10th and 13th week of growth, the larvae are sieved to remove excrement. The sieved larvae are then placed in a plastic tank and fasted for 24-48 hours. After fasting, the larvae are sieved again to remove excrement. The larvae are then placed in water at between 85°C and 100°C and killed for 1-4 minutes, which is called high-temperature killing. During this process, a further step of stunning at a low temperature between -18°C and +4°C for a few minutes is carried out immediately before killing. After killing, the larvae are subjected to a heat treatment at a temperature between 50°C and 150°C for a time period of 1 hour to 24 hours according to the temperature used.

[0078] The resulting larvae have a moisture content between 2 and 15%, more preferably between 3 and 8%, and a water activity of less than 0.9, more preferably less than 0.7.

[0079] A grinding step can be carried out, the term powder here including whole insects previously subjected to heat treatment in the larval or pupal stages, or only morphological parts of these insects reduced to elements less than 3 millimeters, it being understood that this is a description of a specific embodiment of this processing step.

[0080] Such an embodiment can provide results with good performance, however, it should be understood that a person skilled in the art can envision other implementations for processing beetle larvae.

[0081] It should also be noted here that the powder manufacturer does not necessarily perform this killing step and can purchase from a supplier, a beetle farmer, who delivers to them already processed (i.e. killed) beetle larvae, in which case the powder manufacturer would directly perform the enrichment (i.e. UV treatment) step to enrich the powder with vitamin D3.

[0082] For these reasons, it should be understood that the above processing examples are purely illustrative and are not an essential part of the invention.

[0083] -First series of tests: UV treatment stage:

[0084] In this embodiment, processed larvae can be utilized. In this embodiment, these processed larvae can be in the form of whole dehydrated larvae ground into a powder or whole dehydrated larvae that are not ground. In this embodiment, it is contemplated that these processed larvae will be subjected to the UV treatment that is a feature of the present invention.

[0085] In this example, this UV treatment step is carried out in a specific room. In an exemplary embodiment of the invention, this room is A substantially constant temperature between 15 and 35°C, preferably between 22 and 26°C; and Substantially constant humidity of 20-80%, preferably 30-40% relative humidity The beetles are maintained under environmental conditions that allow for the maintenance of the processed beetles in an environment having

[0086] By controlling the environmental parameters (temperature and humidity), better yields can be obtained in the synthesis of Vitamin D3.

[0087] However, other similar environmental conditions can be envisioned by one skilled in the art.

[0088] In this example, the UV treatment continues in a continuous manner for between 2 minutes and 72 hours, although it should be noted that this treatment period can be further shortened.

[0089] In the examples described herein, it is thus sought to enrich processed beetle larvae with vitamin D3 by UV treatment.

[0090] Such UV treatment provides at least one light source of the ultraviolet light source type (i.e., a UV light source) that emits ultraviolet light in the direction of the processed beetle larvae, preferably maintained in a position vertically above the beetle powder or entire beetles.

[0091] In this embodiment, the ultraviolet light emitted by the UV light source in the direction of the beetle larvae is: - consisting of electromagnetic radiation of the UVB type and with a wavelength between 280 nm and 320 nm; and / or -UVA type and consists of electromagnetic radiation with wavelengths between 320nm and 400nm.

[0092] It should be noted here that radiation in the visible range does not affect the synthesis of vitamin D3.

[0093] In the embodiments described herein, the UV light source is positioned at a predetermined distance from the beetle larvae during the phototreatment step, between about 2 cm and 100 cm, preferably between 10 cm and 30 cm.

[0094] In this embodiment, the UV light source has a radiant power between 13 and 125 watts, preferably between 20 and 50 watts.

[0095] In this first embodiment, the UVB light emitted by the UV light source is approximately 75 μW / cm 2 has an irradiance equal to

[0096] Optionally, after this UV step a second heat treatment can be carried out at between 40 and 200° C., preferably between 60 and 100° C., for 1 hour to 24 hours.

[0097] result Of particular interest are the early results obtained in the context of the various studies and tests that have been carried out.

[0098] [Table 1] 1 Live and processed larvae are placed 25 cm from the light source and contained in a tank with dimensions 57 cm x 38 cm x 17 cm. The thickness of the live and processed larvae is a maximum of 1 cm.

[0099] These results are confirmed and elaborated by another series of tests detailed in the remainder of this specification. These additional tests and the analysis of vitamin D3 concentrations (Figures 1 and 2) show that this first series of tests can increase vitamin D3 synthesis by up to 10-fold over the method described in US Pat. No. 5,999,363.

[0100] 2.5 times more production per unit surface area The present invention also allows for increased production of processed larvae per unit surface area.

[0101] Just to be clear, in Patent Document 1 the light source for UV treatment of live larvae is preferably placed at an optimal distance of 25-35 cm above the tank in which the larvae are kept, in order to avoid, inter alia, too high a mortality rate linked to excessive heat.

[0102] With the present invention the light source can be placed between 10-15cm without any effect on mortality.

[0103] In patent document 1, a structure with dimensions of 125 cm x 200 cm x 30 cm, which houses a light source and a tank containing live larvae for 5 days, makes it possible to produce 10.5 kg of live larvae or 3.75 kg of larvae powder containing 24 μg / 100 g of vitamin D3 by dry weight. In the present invention, the same structure over a comparable period makes it possible to produce 9.5 kg, i.e. more than 2.5 times as much larvae powder, containing 50-500 μg / 100 g of vitamin D3 by dry weight, according to the irradiation time. This is made possible by reducing the distance between the light source and the processed larvae, but also because it can act directly on the processed larvae that have previously been subjected to a heat treatment. In contrast to live larvae, which must be cooked or dehydrated and lose 65% of their total mass due to evaporation of water, the larvae no longer lose weight.

[0104] Light processing time reduced to 1 / 100 According to the technique proposed in Patent Document 1, 10 days of light treatment was required to reach 50 μg / 100 g of vitamin D in the dry weight of the larvae.

[0105] After this first series of tests, a concentration of 50 μg / 100 g dry weight is obtained after 1-2 hours of UV treatment.

[0106] These results are highlighted in a second series of studies, detailed below.

[0107] Quantitative analysis of Vitamin D3 was performed by an independent Cofrac-certified laboratory. Quantitation was performed by semi-preparative HPLC followed by reversed-phase HPLC with a UV / DAD detector (265 nm).

[0108] Other studies were also carried out to highlight and optimize the beneficial effects of post-processing UV treatment of the larvae.

[0109] -Second series of tests: During this second series of tests, several samples of Tenebrio molitor larvae are available: S1, S2, S3 and S4. Each sample is different (fresh larvae, live larvae, etc.). These analyses were carried out by an independent laboratory accredited by Coflac, according to the EN 12821: 2009-08 standard.

[0110] During these tests, UV treatment is applied to each of these samples S1, S2, S3 and S4 and the vitamin D3 concentrations of these samples are measured.

[0111] The results and analysis of these tests for samples S1-S4 are shown in Figure 1, which shows in more detail the vitamin D3 concentration of each of samples S1, S2, S3 and S4 after 8 hours of irradiation.

[0112] The first test (sample S1) involved UV treatment of live Tenebrio molitor larvae.

[0113] In this first test, UV treatment is applied to these live larvae as proposed in US Pat. No. 5,399,633. The only difference is that here the vitamin D3 concentration is quantified directly in fresh larvae that have been previously frozen.

[0114] In this first example, the distance of the UV lamp above the live larvae was 20 cm, with the following bulb characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 74.1 μW / cm 2 ;Average temperature: 31.8℃.

[0115] According to Figure 1, this concentration is 3,600 IU / kg fresh weight, i.e. about 10,260 IU / kg dry weight. Conversion to dry larval concentration was obtained by multiplying the fresh larval concentration by 2.85 (Tenebrio molitor larvae have an average water content of 65%), where IU is the International Unit, i.e. 1 IU = 0.025 μg vitamin D3.

[0116] The second test (sample S2) also concerns the UV treatment of live larvae, thus subjecting these larvae to the UV treatment in this second test.

[0117] Here, the distance of the lamp above the larvae sample S2 was 20 cm, and the following bulb characteristics were used: 25 W; 10% UVB, Exo Terra; average irradiance: 75 μW / cm 2 ;Average temperature: 29.44℃.

[0118] These fresh larvae are then processed according to the technology proposed in US Pat. No. 5,399,433 to obtain a powder of dried larvae enriched with Vitamin D3 by UV treatment during the larval stage, where the concentration of Vitamin D3 is measured on dehydrated dried larvae.

[0119] According to FIG. 1, the vitamin D3 concentration of this sample S2 is 7,200 IU / kg of dry weight.

[0120] Another test (sample S3) concerned UV treatment of processed (dead) larvae, and more specifically, uncrushed dried larvae.

[0121] It is understood that in this test the larvae are previously killed and then subjected to the UV treatment proposed according to the invention, and therefore this test represents a specific exemplary embodiment of the invention.

[0122] Note that in this example, killing is performed by immersion in a water bath at 100° C. for 2 minutes, however other techniques are possible for those skilled in the art.

[0123] In this example, the processed larvae were dehydrated at 65° C. for 14 hours. The processed (but uncrushed) larvae were then placed under a lamp located at a distance of 20 cm above the uncrushed dried larvae. The lamp used had the following bulb characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 75 μW / cm 2 ;Average temperature: 30℃.

[0124] According to FIG. 1, the vitamin D3 concentration for this sample S3 now reaches 36,000 IU / kg of dry weight, ie here 5 times greater than the vitamin D3 concentration for the live larvae (samples S2 and S1).

[0125] As far as the fourth test (sample S4) is concerned, this concerns UV treatment of processed larvae, and more particularly of a sample of crushed dried larvae.

[0126] It should be understood that in this example, the Tenebrio molitor larvae underwent the same killing procedure as the larvae in sample S3. After killing, they were further crushed.

[0127] In this example, UV treatment as proposed by the present invention is applied to this sample S4 after killing.

[0128] Here, the same device as above was used, i.e. a UV lamp with the following bulb characteristics: 25 W; 10% UVB, Exo Terra, placed at a distance of 20 cm above the crushed dried larvae. The average irradiance was 75 μW / cm. 2 and the average temperature is 30°C.

[0129] According to FIG. 1, the vitamin D3 concentration for this sample S4 now reaches 72,000 IU / kg of dry weight, i.e. here 10 times higher than the vitamin D3 concentration for live larvae (samples S1 and S2) and 2 times higher than the vitamin D3 concentration for sample S3.

[0130] This second series of tests highlights the advantage of UV treatment on processed larvae (post-kill) (samples S3 and S4) rather than on live larvae (samples S1 and S2) as proposed in WO 2006 / 023996.

[0131] Applicants now argue that, prior to the present invention and the above tests, it was conceivable that processed beetle larvae would, at best, retain the same capacity for synthesis of vitamin D3 as live larvae when faced with UVB radiation.

[0132] It might even be expected that the processing that the larvae underwent would diminish their ability to synthesize vitamin D3.

[0133] However, in a very surprising and unexpected way, the results obtained show the opposite and reveal that irradiation of processed larvae with UVB leads to a more potent synthesis of vitamin D3, with vitamin D3 concentrations 5-6 times higher than those obtained after UVB irradiation of live larvae under similar irradiation times and conditions.

[0134] These unexpected results have a strong impact on the possible yield per unit surface area and therefore on the relevance of industrializing this method with processed larvae. This series of trials also highlights the advantage of grinding the processed larvae prior to UV treatment, which further increases the concentration of vitamin D3 by two-fold.

[0135] - 3rd series of exams: A third series of studies was performed to determine the change in vitamin D3 concentration as a function of UV-B irradiation time.

[0136] During these tests, several samples of Tenebrio molitor type larvae, designated here as S1', S2', S3', S4', S5' and S6', are available. These samples are subjected to various tests.

[0137] The results of the different tests and the analysis of these samples are shown in Figure 2. The analysis was carried out by a Coflac accredited independent laboratory according to the EN 12821:2009-08 standard.

[0138] In this second series of tests, sample S1' is available which corresponds to the defatted beetle powder.

[0139] Here, degreased powder of Tenebrio molitor was available and UV treatment was performed using a UV lamp placed at a distance of 20 cm above the larvae S1'. The UV lamp had the following bulb characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 75 μW / cm. 2 ;Average temperature: 30℃.

[0140] In this example, the extraction of the oily fraction of the larvae is carried out by squeezing the dried larvae that have previously been subjected to blanchiment at 100°C for 2 minutes, followed by dehydration at 65°C for 12 hours.

[0141] According to FIG. 2, after 10 hours of UV irradiation, the vitamin D3 concentration of sample S1' is between 5,000 and 10,000 IU / kg of vitamin D3.

[0142] During this second series of tests, sample S2' now contains live larvae. The developing live larvae are then subjected to a UV treatment by a lamp with the following characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 74.1 μW / cm 2 average temperature: 31.8° C. As with sample S1 in FIG. 1, vitamin D3 concentration analysis is performed on frozen larvae.

[0143] According to FIG. 2, the vitamin D3 concentration of sample S2' is between 15,000 and 20,000 IU / kg after 60 hours of irradiation.

[0144] Sample S3' corresponds to a group of live larvae subjected to UV treatment during the developmental phase. The irradiation conditions are identical to those of S1' and S2'. With equal irradiation times, results are obtained that are virtually identical to those obtained with sample S2', according to FIG. 2. As with sample S2 in FIG. 1, the vitamin D3 concentration analysis is carried out on dehydrated larvae reduced to a powder.

[0145] The tests carried out on samples S1', S2' and S3' correspond to an exemplary embodiment of US Pat. No. 5,399,633, namely UV treatment on live larvae.

[0146] Sample S4' corresponds to whole dried (killed) larvae. Prior to UV treatment, these larvae were processed by killing (blanching at 100°C for 2 min) and then dehydrated. However, these larvae remain unground.

[0147] UV treatment was then applied to this sample S4' during this test by a lamp, the bulb of which had the following characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 75 μW / cm 2 ;Average temperature: 29.44℃.

[0148] Despite the fact that the killed larvae were not crushed, FIG. 2 shows that the concentration of vitamin D3 was high and exceeded 60,000 IU / kg vitamin D3 after 24 hours of UV-B irradiation.

[0149] Finally, in this second series of tests, samples S5' and S6' containing crushed dried larvae are available.

[0150] Sample S5' corresponds to larvae that were cryogenically killed at -18°C, then parboiled at 100°C for 2 min, then dehydrated at 65°C for 14 h and finally crushed.

[0151] Sample S6' corresponds to larvae that were killed by blanching at 100°C for 2 min, then dehydrated at 65°C for 14 h, and finally crushed. Each point in sample S6' contains two separate analyses (N=2; mean ± standard deviation).

[0152] For these samples S5' and S6', the UV lamp is placed at a distance of 20 cm above the live larvae. As with S4', this UV lamp has the following bulb characteristics: 25 W; 10% UVB, Exo Terra; average irradiance: 75 μW / cm 2 ;Average temperature: 29.44℃.

[0153] According to FIG. 2, the concentration of sample S5' is between 90,000 and 100,000 IU / kg of vitamin D3 after 24 hours of irradiation.

[0154] Furthermore, according to Figure 2, the concentration of sample S6' is between 80,000 and 90,000 IU / kg of vitamin D3 after 24 hours of irradiation, which then exceeds 90,000 IU / kg of vitamin D3 after 72 hours of irradiation.

[0155] This third series of tests on vitamin D3 concentrations shows that the present invention makes it possible to increase vitamin D3 synthesis by 4 to 10 times over a given irradiation time with respect to the method described in patent application WO 2006 / 023111.

[0156] This third series of trials also shows that milling can maximize vitamin D3 synthesis, but conversely, results obtained without milling remain highly valued.

[0157] - 4th series of exams: In the above example (FIGS. 1 and 2), the average irradiance of the emitted UVB light is 75 μW / cm 2 It is.

[0158] Subsequent experiments in the context of this fourth series of tests aim to vary the irradiance of UVB rays and to highlight the influence of this irradiance on the synthetic performance of vitamin D3.

[0159] FIG. 3 shows the time course of vitamin D3 concentration in four beetle powder samples, labeled S1'', S2'', S3'', and S4'', respectively, each of which was subjected to UV treatment with a light source having a different irradiance.

[0160] In this example, sample S1″ (black circles; N=2 per time; mean±sd) had a power output of 60 μW / cm in powder. 2 This corresponds to a powder of Tenebrio molitor that has been UV-treated with a UV light source having a UVB intensity (irradiance) of 100 nm.

[0161] In this example, sample S2″ (black triangles; N=2; mean±sd) had a luminance of 60 μW / cm 2 This corresponds to a powder of Alphitobius diaperinus that has been UV-treated with a UV light source having a UVB intensity (irradiance) of 1000 nm for 45 minutes at said power.

[0162] Sample S3'' (open circles; N=2 for each time; mean ± s.d.) had a radiation intensity of 190 μW / cm for the powder.2 This corresponds to a powder of Tenebrio molitor that has been UV-treated with a UV light source having a UVB intensity (irradiance) of 100 nm.

[0163] As for the fourth sample S4″ (open triangles; N=2; mean ± sd), it was 190 μW / cm 2 This corresponds to Alphitobius diaperinus powder subjected to UV treatment with a UV light source having a UVB intensity (irradiance) of 100 nm for 45 minutes.

[0164] Sample S5'' (gray rectangle; N=2 for each time; mean ± s.d.) was 120 μW / cm 2 This corresponds to a powder of Tenebrio molitor that has been subjected to UV treatment for 45 minutes with a UVB intensity (irradiance) of 100 nm.

[0165] In this example, the processing conditions for each of the samples S1'', S2'', S3'', and S4'' are the same. That is, Each UV light source was positioned 25 cm above the powder sample. The average temperature in the UV treatment room is 25°C±1 and the relative humidity is 45%±5. Here, IU is International Unit, i.e. 1 IU=0.025 μg of vitamin D3. The measurement of UVB intensity (irradiance) on the sample is measured using a UVB meter. The analysis of Vitamin D3 in these samples S1'', S2'', S3'', S4'' and S5'' was carried out according to the reference method EN12822:2014 by an independent laboratory accredited by Coflac according to the standard EN12821:2009-08.

[0166] In FIG. 3, it is observed that after 8 hours of UV treatment, increasing the time of exposure to the UV light source does not result in a significant increase in the vitamin D3 concentration in the beetle powder, neither in the first S1″ sample nor in the third S3″ sample.

[0167] Indeed, in this FIG. 3, a plateau in vitamin D3 concentration is observed from 8 hours of exposure.

[0168] During the first experiments carried out by the applicant, the plateau observed in the first sample appeared to correspond to the maximum achievable level.

[0169] This plateau appeared to correspond to the processing of all 7-dehydrocholesterol in the matrix exposed to UV light into cholecalciferol.

[0170] Therefore, a person skilled in the art can, according to his or her common knowledge, assume that the increase in vitamin D3 concentration is proportional to the increase in light intensity, and therefore, by increasing the intensity of the UVB light source, the vitamin D3 concentration can reach a plateau more quickly.

[0171] However, that was not true and was an unexpected result.

[0172] In fact, according to this same Figure 3, by increasing the irradiance by a factor of three, the maximum concentration obtained is increased by a factor of 5 for a given irradiation time (for example, for the same irradiation time of 8 hours for UV treatment, a vitamin D3 concentration of 352,400 IU / kg for the third Tenebrio molitor sample S3″ versus a concentration of 70,000 IU / kg for the first Tenebrio molitor sample S1″); and - the time required to reach a concentration of 20,000 IU / kg is reduced by more than 10 times, for example, the third sample S3'' of Tenebrio molitor requires 3.5 minutes of irradiation time to reach a vitamin D3 concentration of 20,000 IU / kg, compared to 45 minutes for the first sample S1''; is observed.

[0173] Thus, applicants observe that very high concentrations of vitamin D3 are rapidly achieved even with UVB exposure times of less than 10 minutes. 2Using a UV light source with a UVB irradiance of 10000 IU / kg, 26,000 IU / kg is achieved after 5 minutes of irradiation.

[0174] Comparison of the time-dependent changes in vitamin D3 concentration between the first S1'' sample and the third S3'' sample (or between the second S2'' sample and the fourth S4'' sample) shows that the expected proportional relationship between exposure time and UVB light irradiance is not encountered.

[0175] As a consequence, the plateau in the vitamin D3 concentration observed in the first sample S1″ is therefore not caused by complete processing of the sterol to cholecalciferol, as proposed in the above hypothesis.

[0176] Thus, the results obtained during this experiment show that increasing the concentration of vitamin D3 by increasing the irradiance of UVB rays achieves an unexpected performance that is much greater than expected: by increasing the UVB irradiance on the engineered beetle larvae by a factor of three, the maximum concentration obtained is increased by a factor of five and the exposure time required to reach a given concentration is reduced by a factor of ten.

[0177] - 5th series of exams: Ultraviolet light (particularly UVB) is known to amplify oxidative reactions in foods, in other words, significantly increasing the UVB irradiance in beetle powder (even for short periods of exposure) should result in a significant increase in the level of oxidation of its fatty acids to the point where it is potentially unfit for consumption.

[0178] Therefore, in the food sector, the beetle powder must not be irradiated at too high an intensity in order to avoid deterioration of the powder.

[0179] Nevertheless, the applicant carried out the tests in this case with the aim of improving the performance of these methods.

[0180] In this series of tests, applicants therefore tested the effect of significantly increasing UVB irradiance and exposure time on the oxidation of beetle powder.

[0181] During these tests, several oxidation indicators were measured: - Peroxide value (PV). This value allows you to evaluate the degree of oxidation of unsaturated fatty acids in fats. It is an indicator of the onset of oxidation. Peroxides are formed from free radicals that arise in the initial stages of oxidation reactions. -Anisidine value (AV). This value corresponds to the measurement of secondary oxidation products of fats. This value measures the amount of aldehydes (mainly α,β-unsaturated aldehydes). - TOTOX value (TOTal OXidation). This is a measure of the oxidation of the oil based on the peroxide value and the anisidine value. TOTOX value = (2 x PV) + AV. If the TOTOX value is greater than 26, the product is considered hazardous.

[0182] By varying the irradiance and the duration of irradiation, at the end of these tests the following results are obtained, which can be read in Figures 4A to 4D:

[0183] Figure 4A shows the luminance at 60 μW / cm 2 or 190 μW / cm 2 4 shows the peroxide value of Tenebrio molitor powder subjected to UV irradiation at a UVB irradiance of 100 nm for three different times, namely 10 min, 45 min or 480 min (N=2 for each time, mean±sd).

[0184] The concentration of peroxide is observed to increase with UV exposure time.

[0185] However, for a given exposure time and test conditions of the present invention, the level of irradiance does not affect the concentration of peroxide.

[0186] By increasing the level of UVB irradiance by a factor of three, the concentration of peroxides remains similar at a given time, which constitutes a rather unexpected result.

[0187] Figure 4B is 60 μW / cm 2 or 190 μW / cm 2 Figure 1 shows anisidine values ​​of Tenebrio molitor powder subjected to UV irradiation at a UVB irradiance of 100 nm for three different times, namely 10 min, 45 min or 480 min (N=2 for each time, mean ± sd).

[0188] In these tests, it is observed that neither the duration of exposure nor the level of irradiance has any effect on this oxidation index.

[0189] Figure 4C shows the luminance at 60 μW / cm 2 or 190 μW / cm 2 4 shows TOTOX values ​​for Tenebrio molitor powder subjected to UV irradiation at a UVB irradiance of 100 nm for three different times, namely 10 min, 45 min or 480 min (N=2 for each time, mean±sd).

[0190] Up to 8 hours of UVB irradiation, TOTOX values ​​were observed to be below the threshold commonly used in the food industry (dotted line in the figure; TOTOX=26).

[0191] FIG. 4D shows the change in peroxide value of beetle powder (Tenebrio molitor) over 8 h of irradiation (N=2 for each period, mean±sd).

[0192] It was observed that the peroxide value began to reach a critical value from 24 hours. At 48 hours of irradiation, the UVB irradiance levels (60 or 190 μW / cm2) 2 ), due to too much oxidation, the beetle meal is no longer edible.

[0193] Note that in these examples, the UVB light source was placed 25 cm above the powder samples. The average temperature in the UV treatment room was 25° C.±1 and the relative humidity was 45%±5.

[0194] Analysis of peroxide value was performed by titration method by a Koflac certified independent laboratory. Analysis of anisidine value was performed by spectrophotometry by a Koflac certified independent laboratory.

[0195] All of the results obtained during the various experiments carried out are unexpected and surprising and make it possible to realise a very high increase in productivity.

[0196] Indeed, the present invention provides both: - short exposure time (less than 10 minutes); -Very high concentration of Vitamin D3 (190μW / cm 2 130,000 IU / kg of powder for 10 min at an irradiance of - Oxidation levels in line with regulatory requirements This makes it possible to achieve

[0197] All of this performance makes it possible to realize with confidence a reliable and profitable industrialization of the UV treatment method for processed beetle larvae of the present invention.

[0198] Although this detailed description is directed to certain exemplary embodiments of the invention, in no event should this description be construed as having any nature limiting the scope of the invention; indeed, on the contrary, its purpose is to ensure the elimination of possible inaccuracies or any misinterpretation of the claims which follow.

[0199] It must also be noted that the reference signs placed between parentheses in the following claims do not in any way have a limiting character, the sole purpose of these signs being to improve the clarity and understandability of the following claims and the scope of protection sought.

Claims

1. 1. A method for producing a beetle powder, comprising a light treatment step during which at least one light source emits ultraviolet light of the UVB type in the direction of beetle larvae, The UVB type ultraviolet light is 80 μW / cm2 in beetle powder. ２ or more, and the beetle larvae are dehydrated at a temperature between 40 and 250°C, whereby the killed larvae are 2-15% moisture, and / or Water activity (AW) less than 0.7 and the killed larvae may be pulverized prior to the light treatment.

2. The irradiance of the emitted UVB light is 80 to 1,000 μW / cm ２ The method according to claim 1, characterized in that

3. 2. The method according to claim 1, characterized in that the irradiance of the emitted UVB light is between 150 and 250 μW / cm 2 .

4. The method according to any one of claims 1 to 3, wherein the processed larvae have a thickness between 1 and 100 millimeters.

5. 5. The method of claim 4, wherein the processed larvae have a thickness of between 5 and 15 millimeters.

6. The ultraviolet light emitted by the at least one light source in the direction of the beetle larvae during the phototreatment step is - consisting of electromagnetic radiation of the UVB type and with wavelengths between 280 nm and 320 nm; and / or The method according to any one of claims 1 to 3, consisting of electromagnetic radiation of the UVA type and having a wavelength between 320 nm and 400 nm.

7. The method according to any one of claims 1 to 3, wherein during the light treatment step, said at least one light source is positioned at a predetermined distance between 1 and 100 cm from the beetle larvae.

8. 4. The method according to claim 1, wherein during the light treatment step, the at least one light source emits ultraviolet light in the direction of the processed beetle larvae according to a treatment range between 10 seconds and 24 hours.

9. The method of claim 8 , wherein the treatment range is achieved continuously or cumulatively.

10. 4. The method according to any one of claims 1 to 3, wherein during all or part of the light treatment step, the processed beetle larvae are maintained in an environment having a substantially constant temperature between 15 and 35°C.

11. 4. The method according to any one of claims 1 to 3, wherein during all or part of the light treatment step, the processed beetle larvae are maintained in an environment having a substantially constant humidity of between 20 and 80% relative humidity.

12. The method according to any one of claims 1 to 3, wherein the beetles are selected from the following species: Tenebrio molitor, Alphitobius diaperinus.

13. A beetle powder obtainable by carrying out the manufacturing method according to any one of claims 1 to 3, characterized in that it contains 130,000 IU / Kg of vitamin D3 and has a TOTOX oxidation index calculated from the PV peroxide value and the AV anisidine value, i.e., TOTOX oxidation index = (2 x PV) + AV, of 26 or less.

14. 14. Use of the beetle powder according to claim 13 for human or animal food.

15. The use according to claim 14, wherein the powder is used as a dietary supplement.

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