Search Results (48)

Due to their nutritional value and sustainability, edible insect-based foods are gaining popularity in Europe. Their use is regulated by EU legislation, which defines authorised species and sets labelling requirements. Molecular tools are being developed to authenticate such products. In this study, yellow mealworm (Tenebrio molitor) larvae authorised for human consumption were fed wheat flour-based diets containing varying proportions of house cricket (Acheta domesticus) flour for 21 days. This was followed by a 48 h starvation period to assess the persistence of insect DNA in the digestive tract. Two novel, species-specific, single-copy markers were designed: ampd gene for the Acheta domesticus and MyD88 gene for the Tenebrio molitor. These were applied using qPCR and ddPCR. Both methods successfully detected cricket DNA in the guts of starved larvae. Linear regression analysis revealed a strong, statistically significant correlation between the proportion of Acheta domesticus flour in the diet and the normalised relative quantity of DNA. ddPCR proved to be more sensitive than qPCR, particularly in the detection of low DNA levels. These results suggest that the presence of DNA from undeclared insect species in edible insects may be indicative of their diet rather than contamination or adulteration. This highlights the importance of contextual interpretation in food authenticity testing. Full article

Pre-, pro-, and post-biotics have been used with success in several commercially grown insect species to increase yields and improve health outcomes. However, few studies have been published evaluating the use of nutritional supplements in Acheta domesticus. For this study, we fed day-old, farm-raised, A. domesticus a Saccharomyces cerevisiae postbiotic product at one of three different inclusion rates (0, 0.25, and 0.5%) for 32 days. Crickets were analyzed for differences in average weights, total biomass, percent survival, nutritional analyses, viral qPCR, and 16S/18S microbiomes. Crickets receiving the 0.5% inclusion feed trended towards having a higher total biomass (F = 3.823, p = 0.052) and a higher percent survival per bin (F = 3.667, p = 0.057) than the crickets receiving lower inclusion feeds. No significant differences were found in viral prevalences or loads. Significant changes to the microbiomes were mostly defined by increased abundances of presumed beneficial bacteria (Akkermansia, Catenibacillus, and Odoribacter) in the groups receiving postbiotics rather than by losses of harmful bacteria. For the 18S results, there was an increased abundance of a Gregarian apicomplexan, Leidyana erratica in the treatment groups. Overall, the 0.5% inclusion feed appeared to be beneficial and further study investigating other forms of feed additives is warranted. Full article

The possibility of designing the nutrient composition of invertebrate biomass was investigated. Two model species of terrestrial invertebrates, the house cricket Acheta domesticus (Linnaeus, 1758) and the earthworm Eisenia fetida (Savigny, 1826), were studied after feeding on substrates alternately enriched with certain nutrient precursors proposed in single and double doses. Crickets and earthworms showed similar tendencies to increase the B vitamin content of those vitamins whose initial level was high. Double-dose enrichment of the food substrate increased the levels of vitamin C, fat-soluble vitamins and most B vitamins. In a control group of crickets, vitamin C levels were 1.5 times lower than in a control group of earthworms. After enrichment of the feed substrate, the vitamin C content in the biomass of the crickets did not change significantly, but in the earthworms it increased significantly. The content of a wide range of minerals did not change after single-dose enrichment, but some micro-elements such as Pb and Se decreased significantly in earthworms after double-dose enrichment of the feed substrate. The calorific value of crickets was twice that of earthworms and did not change significantly after double-dose enrichment. It is shown that the nutrient composition of invertebrate biomass can be increased by enriching the feed substrate with precursors. The most effective increases are observed for all vitamins and several minerals. The results can be used to achieve specific nutrient concentrations in biomass for food and medical purposes. Full article

The utilization of insects as a source of essential nutrients holds considerable promise, with the potential to serve as both feed and food. Consequently, there is a necessity to develop control systems, as the undeclared addition of insects to food products and/or non-compliance with labelling regulations may pose health risks and result in financial losses for consumers. This review describes methods for identifying and detecting insect species by targeting biomolecules such as DNA, proteins, saccharides, and metabolites, with a particular focus on DNA-based approaches. This review provides a detailed overview of the application of polymerase chain reaction (PCR) and DNA sequencing methods that are suitable for the analysis of edible and forage insects. The main focus is on identifying species that are approved for use as novel foods or insect feeds within the European Union (e.g., house cricket (Acheta domesticus), common mealworm (Tenebrio molitor), migratory locust (Locusta migratoria), lesser mealworm (Alphitobius diaperinus), black soldier fly (Hermetia illucens), banded cricket (Gryllodes sigillatus), field cricket (Gryllus assimilis), silkworm (Bombyx mori)). However, insect species of global relevance are also discussed. The suitability of DNA analysis methods for accurate species identification, detection of (un)labeled contaminants, and monitoring of genetic diversity has been demonstrated. Full article

The gut microbiota is pivotal to chickens’ overall health, influencing digestion, nutrient absorption, and immune function. Dietary compounds significantly impact gut microbiota composition. House crickets (Acheta domesticus) have emerged as an alternative protein source for animal feed, rich in proteins and beneficial fatty acids. This study compared the gut microbiota in the cecum and ileum of Thai indigenous chicken breeds (Betong Chicken, white feather with black bone chicken, and black feather with black bone chicken) fed with or without house crickets. Using Oxford Nanopore Technology of 16S rDNA, this study found a similar relative abundance of gut bacteria across groups, with dominant bacteria including Firmicute, Bacteroidetes, Proteobacteria, and Actinobacteria. LEfSe analysis identified differential abundance of beneficial bacteria, such as Ruminococcaceae, Rikenella, and Deferribacteres, in the cecum of the black feather with black bone chicken after cricket feeding. Additionally, Lactobacillaceae exhibited differential abundance in the ileum of this breed post-cricket diet. Consequently, this study provides new data into the gut microbiota of Thai indigenous chickens. It suggests that house cricket diets did not significantly alter microbiota diversity but may enhance beneficial bacteria in certain breeds. Full article

The scientific interest in edible insects as an alternative source of high-value protein for the human diet has increased drastically over the last decade. Edible insects harbour enormous potential in terms of planetary health. Their lower water and land use, lower feed conversion ratios, and overall lower global warming potential paired with a high nutritional value compared with conventional livestock are key drivers towards an environmentally sustainable diet. However, low consumer acceptance, as well as regulatory challenges, have slowed down the success of edible insects in Western countries, despite edible insects being consumed regularly all over the world. To date, four edible insect species have been approved as novel foods in the European Union—namely yellow mealworm (Tenebrio molitor), migratory locust (Locusta migratoria), house cricket (Acheta domesticus), and lesser mealworm (Alphitobius diaperinus). Depending on the species, they have a high protein content (48–67%), with a beneficial indispensable amino acid profile, high fat content (21–39%), with a high content of unsaturated fatty acids based on the dry matter, and contain reasonable amounts of minerals and vitamins. Unlike other animal-based foods, edible insects contain dietary fibre. Data on the bioavailability of nutrients in humans are scarce. Although numerous publications have investigated the nutritional profiles, environmental impacts, and future perspectives of edible insects, here, those findings are reviewed critically, as some publications were partially contradictory or related to selected species only. In this narrative review, we emphasise that edible insects could play a key role in a changing world with a steadily increasing demand for nutritionally valuable food and the depletion of natural resources. Full article

Edible insect powder, particularly from the cricket Acheta domesticus L., is a promising sustainable alternative to traditional livestock-derived protein. Insects provide high protein content, fibre, and essential minerals, making them suitable for food applications. This study investigates the viability of alternative diets for rearing A. domesticus. Two experimental diets were tested: RI [50% horticultural by-products (HP) + 50% commercial diet (CD)] and RII (33% HP + 33% CD + 33% fish by-products). The results demonstrated that both diets were suitable for cricket rearing. Crickets reared on diets RI and RII produced, respectively, insect powders FI and FII, which were evaluated for their nutritional, bioactive, and microbiological attributes. Both powders exhibited high protein content (≈60%), all essential amino acids, higher mineral content than traditional protein sources, and met European Union food safety standards. Diet composition influenced powder characteristics: FI showed higher antioxidant activity and saturated fat content, while FII contained more protein, ash, minerals, and monounsaturated fatty acids. These findings underscore the potential of using industrial by-products to promote a circular economy in insect farming and suggest pathways for further research. However, since insects can bioaccumulate toxic elements, such as Hg, from diets, caution should be taken when considering fish by-products. Full article

Global population is projected to reach 9.1 billion by 2050, emphasizing the need for increased food production. Edible insects, such as house crickets (Acheta domesticus), emerged as promising due to higher nutritional value and efficient feed conversion rates compared to conventional protein sources. Incorporating insect powders into new food products can improve consumer acceptance but often leads to poor technological food processing functionality and/or undesirable organoleptic characteristics. Protein isolates have proven to be effective in enhancing this functionality and consumer acceptance, but existent protein extraction methods still lack improvements concerning the optimization of protein extraction rates. This study aimed to address this gap by developing and comparing the yield of three different protein extraction methods using sodium hydroxide, ascorbic acid or alcalase from house crickets (Acheta domesticus) for food applications. Protein extraction was performed on cricket powder with a mean protein content of 46.35 g/100 g, and the results were evaluated. The enzymatic method shows the highest protein extraction rate at 69.91% with a mean protein content of 60.19 g/100 g, while extraction with NaOH or ascorbic acid resulted in rates of 60.44 and 46.34%, respectively. Further studies on technological food processing functionality and sensorial evaluation of products developed with this protein extract are recommended. Full article

As sales have increased in recent years, enhancing production processes and quality has emerged as a significant challenge for the cricket industry. In this study, we investigated the impact of supplementing feed with black soldier fly larvae (BSFL) on the yield, nutritional characteristics, and protein digestibility of Acheta domesticus. In addition, the bioactivity of house cricket proteins was compared. The results demonstrated that incorporating BSFL into feed improved the yield and nutritional characteristics of house cricket, such as crude protein levels and total phenolic content. Alterations in amino acid and fatty acid profiles also enhanced their nutritional value. In addition, 5% BSFL and 10% BSFL were more readily digested, and the protein hydrolysate of the groups fed BSFL demonstrated stronger antioxidant activity. The findings of this study can offer valuable insights into house cricket farming, protein processing, and the development of new food products. Full article

This research emphasizes the application of ultrafine grinding technologies to optimize the extraction process of chitin from house crickets (Acheta domesticus), aiming to establish a more sustainable and efficient production method. This study evaluates the extraction efficiency of two advanced ultrafine grinding techniques: (1) fluidized bed jet milling (FBJM) and (2) graded impact milling (GIM), alongside a traditional hand sieving method. A comprehensive analysis of the chemical composition of the extracted chitin was performed, measuring critical parameters such as moisture content, residual ash, and protein levels, while also assessing its physicochemical properties. The results demonstrate that the implementation of ultrafine grinding methods significantly enhances both the yield and purity of chitin, while also reducing raw material consumption. This highlights the potential of house crickets as a sustainable source of biomaterials. The findings provide essential theoretical insights and practical guidance for the future development and application of chitin derived from insects. Full article

This study aimed to determine the nutritional properties of selected edible insects as a potential future food. A total of eight species of edible insects, including the dubia roach (Blaptica dubia), super worm (Zophobas morio) larvae, locust (Locusta migratoria), silkworm (Bombyx mori) pupae, house cricket (Acheta domesticus), sago palm weevil (Rhynchophorus ferrugineus) larvae, black soldier fly (Hermetia illucens) larvae, and grasshopper (Oxya Yezoensis) have been obtained and analyzed for their macronutrient contents. Results showed that grasshopper (68.18 g/100 g) has the highest protein content, which is comparable to conventional animal meats. This indicates that the edible insect is a valuable alternative protein and provides essential amino acids. Thus, some edible insects could serve as a source of sustainable nutrients for daily requirements and mitigating food insecurity in the future. Full article

The consumption of edible insects is a promising approach to meet the increasing global demand for food. Commercialization of edible insects in the EU is regulated by the Novel Food regulation. To date, the yellow mealworm (Tenebrio molitor larva), the migratory locust (Locusta migratoria), the house cricket (Acheta domesticus), and the buffalo worm (Alphitobius diaperinus larva) have been authorized in the EU for human consumption. We aimed to develop a method based on DNA barcoding and high-resolution melting (HRM) analysis for the identification and differentiation of these four EU-authorized edible insect species in food. A primer pair previously designed for DNA metabarcoding, targeting a ~200 bp sequence of mitochondrial 16S rDNA, allowed discrimination between the four insect species in highly processed food. However, house cricket and migratory locust could not unambiguously be differentiated from tropical house cricket, desert locust, superworm, cowpea weevil, and sago worm, respectively. This problem could be solved by designing primers specific for house cricket and migratory locust. By combining these primers with the insect primers, additional polymerase chain reaction (PCR) products for house cricket and migratory locust were obtained, resulting in more complex melt curves compared to the unauthorized insect species. The optimized PCR-HRM assay is a very cost-efficient screening tool for authentication of EU-authorized edible insect species in food. Full article

To support the role of insects as sustainable feed and food ingredients, evaluating their potential microbiological risk and safety is crucial. In this study, we investigated the presence of antimicrobial resistance (AMR) genes in selected live opportunistic pathogenic bacteria isolated during the rearing process from clinically healthy farm-reared crickets. Molecular analysis was performed by wholegenome sequencing of a total of 14 of these bacterial strains, 7 from house crickets (Acheta domesticus) and 7 from banded crickets (Gryllodes sigillatus), belonging to Enterobacteriaceae, Staphylococcaceae, Enterococcaceae, and Bacillaceae families. The β-lactam AMR genes (bla_OXY2-6, bla_ACT-16, and bla_SHV variants) were the most predominant genes identified, mainly in Enterobacteriaceae strains and in association with fosfomycin (fosA) and oqxAB efflux pump complexes. In addition, blaZ and mecA genes were detected in Bacillus cereus and Mammaliicoccus sciuri strains isolated from both insect species. Genetic mobile elements including IncFIA, IncFIB, IncHI1A, IncHI1B, rep13, and Col3M-like plasmids were detected in Klebsiella pneumoniae, Enterobacter hormaechei, Staphylococcus arlettae, and B. cereus, respectively. The results indicate that, not only in the final product but also during the insect-rearing process, microbial safety control, regarding the presence of pathogenic bacteria and AMR genes, is essential for effectively decreasing the microbiological risk between cricket batches within their environment and in terms of the related feed and food chain. Full article

The house cricket, Acheta domesticus (Linnaeus), is often used as a food source for the maintenance of imported fire ants under laboratory rearing. It was found that both red imported fire ants, Solenopsis invicta Buren, and black imported fire ants, S. richteri Forel, consumed most of the soft tissues of female crickets, but avoided their eggs by disposing of them on refuse piles. Bioassays using freshly collected cricket eggs showed that ants first retrieved eggs into their nests and then discarded them onto the refuse piles. The major chemicals on the surface of cricket eggs were found to be fatty acids, including lauric, myristic, palmitoleic, palmitic, linoleic, oleic, and stearic acid. Fatty acids are well-known death cues of insects and elicitors of widespread necrophoric behavior in ants. It was shown that both the cricket egg extract and the reconstructed fatty acid mixture elicited the necrophoric behavior of S. invicta; however, they never elicited retrieving behavior. Unknown chemicals on cricket eggs, other than fatty acids, might be responsible for the retrieving behavior. Interestingly, cricket eggs had a very similar fatty acid profile to that of dead ants collected from refuse piles. Possible causes for such a strong match in fatty acid profiles between dead ants and cricket eggs are discussed. Full article

Proteins from insect production represent an interesting (environmentally friendly) option or supplement to commercial livestock farming. At present, however, the larval stages of T. molitor (mealworm) and A. diaperinus (buffalo worm) have been authorized as food for human consumption EU-wide, as have the nymph and adult stages of Locusta (L.) migratoria (Locusta migratoria, Linnaeus, 1758) and Acheta (A.) domesticus (house cricket, Acheta domesticus, Linnaeus, 1758). However, there is the problem that insects that are recognizable as a whole tend to be avoided by consumers, especially in the European region, as they are reminiscent of living things and can cause aversion and disgust in consumers. Against this background, in the present study, five batches of two types of cooked sausages were produced: on the one hand, with turkey, and on the other hand, with pork lean meat as a base. In different formulations, 10% and 20% of the meat contents (turkey or pork) in these meat products were replaced by deep-frozen, pulverized T. molitor and A. diaperinus larvae. The effects of the addition of these insects in the products on the microbiological and physicochemical parameters of these cooked sausages, compared to a product without insect content, directly after heating, were investigated. After production, a storage trial was also carried out to determine whether possible insect ingredients could influence the growth of inoculated bacterial species (Bacillus (B.) cereus, Escherichia (E.) coli, Listeria (L.) monocytogenes, and Campylobacter (C.) jejuni) and how the addition of insect larvae affectsthe sensory and physicochemical properties during storage. The study showed that the products with insects had reduced lightness (turkey p C = 0.025), increased yellowness (pork p S = 0.0009, p C < 0.0001 and turkey p C = 0.0027) and a reduced red color (pork p S < 0.0001, p C = 0.0001) after heating when compared to the cooked sausages without insects. However, no significant differences between the various cooked sausages with or without insects in terms of cooking loss, firmness, and protein, ash, and fat or water contents were found. The microbiological tests showed, on the one hand, that the prior microbial reduction (e.g., in the form of blanching) of the insect larvae was essential in order to guarantee the flawless microbiological quality of the cooked sausages and, on the other hand, that the addition of insects to the cooked sausages did not significantly affect the growth of the inoculated bacterial species and that no sensory differences could be detected during storage. Despite the significant color effects on the product, A. diaperinus and T. molitor larvae would be suitable as protein or meat alternatives in cooked sausages, but they would have to undergo pre-treatment, primarily with regard to microbiological safety. The extent to which a complete replacement of meat is possible has to be investigated in further studies. Full article