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Insects are seen as a solution to the increasing demand for protein sources for food. However, entomophagy has unfortunately been linked to allergic reactions in Europe with people with professional contacts. As mealworms (Tenebrio molitor) and crickets (Acheta domesticus) have recently become commercially available (both whole or in food formulation) in several European countries, this research assessed the cross allergenicity of arginine kinase (AK). Based on the collection of sera from a entomology laboratory staff, oven cooked insects but also purified AK fractions were tested. Immunoblotting against the protein extracts revealed different Immunoglobulin E reactivity of sera according to the insect target species: two bands (40 and 14 kDa) for crickets and a pattern including light responses at 17, 25 and 37 kDa for mealworms. Focusing on AK, low specific allergenicity was here illustrated and discussed in relation to the development of a safe edible insect consumption by humans.

To address the future challenge of food availability (9 billion people on earth by 2050), non-common sources of proteins need to be investigated. Insects are consumed mainly in Africa, Asia and South America, but entomophagy is now being increasingly promoted in Europe and North America. In addition to consumption in raw form, insects are often cooked, which represents an important guarantee for sanitation purposes. Little information is available on the influence of such treatment and its effect on the nutritional value of the resulting insect food. The aim of this study was to determine, depending on the heat treatment, the quality of the proteins of two edible insects, using the protein digestibility-corrected amino acid score (PDCAAS) and a rat bioassay. The insects were adult house crickets (Acheta domesticus) and the larvae of mealworms (Tenebrio molitor). Both insects, not heated or heat-treated by oven-cooking at 150 °C for 30 min or at 200 °C for 10 min and by autoclaving at 120 °C for 25 min, were fed to rats and evaluated for ingestion, digestibility and nitrogen retention and compared with a control casein diet. The growth performance of rats fed mealworm larvae, and to a lesser extent house crickets, was hampered by a deficiency in sulphur-containing amino acids (AA) in not heated insects. Then, the nitrogen retention of diets formulated with oven-cooked or autoclaved insects was reduced in rats because the AA profile was negatively modified by the heat treatment. Cooking insects at 200 °C for 10 min seemed the most appropriate for maintaining a high nutritive value in growing rats. However both tested insect-species are promising as human food ingredients because of (1) their high protein digestibility in the not heated state (84-92%) as well as after being heated (84-90%); and (2) their AA profile, which meets human dietary requirements (69-84% for PDCAAS).

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and compared with those of Tenebrio molitor larvae. A. domesticus, Co. discolor, Ch. parallelus and T. molitor larvae were found to contain approximately 15%, 13%, 10% and 32% lipids on dry weight, respectively. The lipids from three Orthopterans contain much higher amounts of essential fatty acids than those of T. molitor larvae. The two Orthopterans of the suborder Ensifera i.e., A. domesticus and Co. discolor contain linoleic acid in major quantities, while Ch. parallelus of the suborder Caelifera, contain α-linolenic acid in major quantities. The consumption of linoleic and α-linolenic fatty acid is linked with numerous health promoting effects. The factors that contribute to differences in fatty acid profiles of these insects are being discussed. At last the nutritional parameters including polyunsaturated to saturated and omega 6 to omega 3 fatty acid ratios of these insect lipids are also being discussed to understand the potential role of these lipids in human nutrition.

During the past few years, entomophagy has been increasing in significance. As insects are generally high in protein, they are principally considered as meat substitutes. Nevertheless, in Western countries, meat substitute consumption is actually very low, principally due to food neophobia and poor sensory qualities in comparison with meat. In insect particular case, food neophobia is clearly high. To reduce insect food neophobia, previous studies suggest to insert invisible insect in food preparation and/or to associate them with known flavors. In this study, a survey on entomophagy perception and hedonic tests were realized to assess the level of sensory-liking of hybrid insect-based burgers (beef, lentils, mealworms and beef, mealworms and lentils). Participants’ overall liking of the four burgers differed between genders and was influenced by burger appearance and taste. Women clearly preferred beef burger appearance, whereas men preferred the appearance of beef and insect-based burgers. Concerning insect-based burger taste, participants (men and women) rated it intermediately, between that of the beef and lentil burger, with a preference for the mealworm and beef burger. Results also showed that people with previous entomophagy experience was limited but that they gave globally higher ratings to all preparations. In conclusion, insect tasting sessions are important to decrease food neophobia, as they encourage people to “take the first step” and become acquainted with entomophagy. Nevertheless, insect integration into Western food culture will involve a transitional phase with minced or powdered insects incorporated into ready-to-eat preparations, as people are not ready to add insects to their diets in “whole form.”

Summary: Risks and valorization of insects in a food and feed contextIn a context of dwindling lands and resources, associated with a strong dependence on protein for feed and food, new methods of production and/or new food must be developed without affecting the quality of food, natural habitat and biodiversity of animal and vegetable species. As such, insects appear more and more as a solution of the future. To date, the consumption of insects is indicated by the term “entomophagy”, from the Ancient Greek “entomos” meaning insect and “phagos” meaning food. In such a context, a global evaluation of entomophagy seems essential before allowing the introduction of this practice in animal and human feed. Firstly, through this review, elements concerning the potentialities of insect valorization and their nutritional qualities will be brought. Secondly, the environmental impact of such a practice as well as the biological, chemical, physical or sanitary risks and even the potential presence of allergens and a...

BACKGROUND The health status of the indigenous people of Ratanakiri Province, Cambodia, is significantly lower compared with that of the rest of the nation. The domestication and mass production of insects may represent a sustainable, cost effective and high quality alternative source of protein to traditional livestock. This study aimed to optimise a cheap and residential cricket breeding system based on unused wild resources. The development of crickets, Teleogryllus testaceus (Walker), under seven diets composed of taro aerial parts, young cassava leaves, young cashew leaves and brown rice flour (with or without banana slices), versus a traditionally used broiler feed diet was studied. RESULTS Cricket mortality was low in all diets, except the two cashew-based diets. Total biomass was significantly higher under the broiler feed, in addition to the two diets containing a combination of cassava leaf powder and brown rice. Yet, crickets fed with the taro diet had the highest percentage of protein. Concerning the breeding system cost, units using cassava leaves were the cheapest. CONCLUSION Diets based on cassava leaves seem to be the most promising. Nevertheless, to produce crickets with a high body mass and a high protein level, a new experiments must be devised in which cassava leaf maturity will be adapted to fit with the cricket growth stage. Moreover, to reduce the cost of the breeding units, handmade local products should be used instead of purchased components. © 2015 Society of Chemical Industry

We present an overview of the diversity, distribution, nesting behaviour, traditional knowledge and use of stingless bees in Gabon, Central Africa. A total of 16 species were recorded and grouped into 5 genera: Cleptotrigona, Dactylurina, Meliponula, Hypotrigona and Liotrigona. The species identification of Hypotrigona and Liotrigona based on morphological characteristics remains difficult. The distribution of stingless bees is poorly documented in Gabon. However, several species have been reported to have wide distributions. Stingless bees build exposed nests or nests in tree cavities, in the ground or in termite mounds and anthills. The inhabitants of Gabon hunt honey to support traditional medicine. Future research should focus on investigating how human activities impact the diversity of stingless bees in Gabon, along with assessing the threats and constraints of implementing a breeding programme for stingless bees.

In the present study, soil samples and earthworms were collected from wheat-cultivated fields under four agricultural practices: (1) conventional tillage with crop residues incorporated into the soil (CT/IN), (2) conventional tillage with crop residues exported from the field (CT/OUT), (3) reduced tillage with crop residues incorporated into the soil (RT/IN), and (4) reduced tillage with crop residues exported from the field (RT/OUT). Agricultural practices were applied on Luvisol soil for four consecutive years. The purpose of this study was to investigate the influence of agricultural practices on soil organic matter and earthworm communities and their interactions with soil properties and crop residues. Results indicated that crop residue exportation affected soil properties and earthworm communities. The penetration resistance (PR) measured to a depth of 50 cm rose with increasing soil depth in all treatments. For each depth, measures of soil physicochemical properties showed significant differences among treatments. A major difference was observed between IN and OUT treatments, suggesting the exportation of crop residues will limit earthworm abundance and biomass. Findings indicate endogeic and epi-anecic groups appears to be highly affected by tillage and crop residues exportation. Results emphasize the influence of crop residue exportation on the earthworm community, as well as the influence of earthworm activity on PR, P and K nutrients change; these processes are closely linked.

Experiments were carried out to investigate the egg-laying behaviour of the maize weevil, Sitophilus zeamais Motsch. (Coleoptera: Curculionidae) in uninfested and previously infested (termed conditioned here) maize grains. The number of offspring produced and preferred grain type of the weevil were examined under laboratory conditions, along with the effect of the presence of egg plugs on the oviposition site selection. The number of progeny produced was higher in conditioned maize. The highest and lowest number of adults emerged from conditioned and uninfested maize, respectively. S. zeamais individuals were significantly more attracted to conditioned grains compared to uninfested grains. S. zeamais females laid more eggs on host grains already bearing conspecific eggs (that is, conditioned) compared to clean grains (that is, uninfested). The number of eggs per grain showed a contagious distribution because females laid additional eggs on grains already infested with more than one egg. The results of this study indicate the possible role of the aggregation pheromone, intraspecific competition and egg marking in the observed egg-laying behaviour pattern of this pest species. Key words: Maize weevil, egg, aggregation pheromone, oviposition behaviour, host marker.

Mealworms are new food products in Europe, but consumers do not know how to cook them. Although cooking could increase the safety, acceptability, palatability, and digestibility of insects, the heating process could have deleterious effects on protein and lipid quality. Therefore, this study characterized the effects of different household cooking methods (boiling, pan-frying, vacuum cooking, and oven cooking) on the microbial load and nutritive value of mealworms, with a focus on protein digestibility and fatty acid composition. Boiling and cooking under vacuum were the most efficient techniques to reduce microbial load while maintaining the high levels of protein and polyunsaturated fatty acids of mealworms. Cooking method-related changes were very low on macronutrients content except for pan-fried mealworms which exhibited the highest lipid content. Cooking slightly changed fatty acid composition of mealworms by principally decreasing their level of saturated fatty acids but also increased the in vitro crude protein digestibility of mealworms.

ResumeLes observations faites sur deux cucurbitacees africaines, Lagenaria siceraria Molina (Standl.) et Citrullus lanatus Thumb (Matsum & Nakai) ont permis d’inventorier l’entomofaune (utiles et ravageurs) associee a la pratique culturale. L’evaluation des degâts occasionnes par les ravageurs a mis en evidence leur impact sur la production. Suivant un schema experimental, des parcelles de 49 m2 traitees au CYPERCAL 50 EC (50 g/l de Cypermetrine) et au FURADAN 5G (50 g/kg de Carbofuran) et non traitees ont ete disposees en blocs aleatoires. Les observations ont porte sur l’identification et le denombrement des insectes, sur le pourcentage de plants attaques ainsi que sur la production de baies mures et de graines. Au total, 71 especes ont ete identifiees, reparties en 41 familles et 10 ordres (Coleopteres, Hymenopteres, Dipteres, Lepidopteres, Orthopteres, Homopteres, Heteropteres, Dictyopteres, Odonates et Dermapteres). Les principaux ravageurs appartiennent a la famille des Chrysomelidae (Lamprocopa occ...

Earthworms increase the availability of heavy metals in some situations and aid in maintaining the structure and quality of soil. The introduction of earthworms into metal-contaminated soils has been suggested as an aid for phytoremediation processes. In Wallonia, Belgium, a century of industrial metallurgic activities has led to the substantial pollution of soils by heavy metals, including copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd), due to atmospheric dusts. Two plant species, Vicia faba and Zea mays , and earthworms ( Eisenia fetida ) (Savigny, 1826) were exposed to different concentrations of long-term-contaminated soils for 42 days. The soil samples, which were collected from the land surrounding a former Zn-Pb ore-treatment plant, exhibited different levels of heavy metals. Our aim was to evaluate the role of earthworms E. fetida on the availability of metals in soils and their effects on metal uptake by V. faba and Z. mays plants at different soil concentrations. The results suggest that earthworms and plants modified the availability of metals in contaminated soils after 42 days of exposure. Earthworm life-cycle parameters were affected by metal contamination and/or the addition of plants; cocoon production and weight were more responsive to adverse conditions than earthworm survival or weight change. The concentrations of Pb and Cd in earthworm tissues decreased in the presence of plants. Results showed that metal accumulation in plants depended on the metal element considered and the presence of earthworms. However, the presence of earthworms did not change the concentrations of metals in plants, except for Cd. In the presence or absence of earthworms, V. faba accumulated higher concentrations of Cu and Zn compared with Z. mays , which accumulated higher concentrations of Cd. These findings have revealed that earthworm activities can modify the availability of heavy metals for uptake by plants in contaminated soils. Moreover, the study results show that the ecological context of phytoremediation should be broadened by considering earthworm-plant-soil interaction, which influence both the health of the plant and the uptake of heavy metals by plants.

The health status of the indigenous people of Ratanakiri Province, Cambodia, is significantly lower compared with that of the rest of the nation. The domestication and mass production of insects may represent a sustainable, cost effective and high quality alternative source of protein to traditional livestock. This study aimed to optimise a cheap and residential cricket breeding system based on unused wild resources. The development of crickets, Teleogryllus testaceus (Walker), under seven diets composed of taro aerial parts, young cassava leaves, young cashew leaves and brown rice flour (with or without banana slices), versus a traditionally used broiler feed diet was studied.Cricket mortality was low in all diets, except the two cashew-based diets. Total biomass was significantly higher under the broiler feed, in addition to the two diets containing a combination of cassava leaf powder and brown rice. Yet, crickets fed with the taro diet had the highest percentage of protein. Concerning the breeding system cost, units using cassava leaves were the cheapest.Diets based on cassava leaves seem to be the most promising. Nevertheless, to produce crickets with a high body mass and a high protein level, a new experiments must be devised in which cassava leaf maturity will be adapted to fit with the cricket growth stage. Moreover, to reduce the cost of the breeding units, handmade local products should be used instead of purchased components.

The present study quantified egg and pupal cannibalism, and interspecific predation on eggs and pupae, by larvae and adults of seven species of flour beetle ( Tribolium spp.) under laboratory conditions: T. anaphe , T. brevicornis , T. castaneum , T. confusum , T. destructor , T. freemani , and T. madens . 2. Variation among species in cannibalism and predation propensities did not reflect taxonomic affinities within the genus, indicating that these behaviours were shaped by ecology at species level. 3. Within species, larvae and adults displayed different propensities for cannibalism and predation, leading to the conclusion that these behaviours evolve independently in the two life stages. 4. All species behaved as intraguild predators to some degree, especially in the adult stage. 5. Three general patterns of cannibalism and predation were described by principal component mapping and cluster analysis. 6. The first group comprised three cosmopolitan pest species that were more voracious as adults than as larvae: T. castaneum , T. confusum , and T. destructor . It is proposed that stored product environments select for high adult voracity because the costs associated with emigration from such rare, but resource-rich, habitats intensifies interference competition among adults. 7. The second group consisted of species that inhabit natural environments and that were more voracious as larvae: T. anaphe , T. freemani , and T. madens . Habitats for these species are probably numerous, but generally poor in quality, a situation that intensifies larval competition, while favouring earlier adult emigration. 8. The largest species, T. brevicornis , demonstrated inconsistent voracity between life stages and was the only species with chemically defended pupae. 9. It is proposed that consumption of eggs provides primarily nutritional benefits, whereas consumption of pupae has a more important role in interference competition.