Nutritional and sensory quality of edible insects

Bioactive Compounds and Antioxidant Composition of Nut Bars with Addition of Various Edible Insect Flours

Edible insects represent a new functional source of nutrients that can contribute to solving nutritional deficiency problems. The antioxidant potential and bioactive compounds of nut bars with the addition of three edible insects were evaluated. Acheta domesticus L., Alphitobius diaperinus P. and Tenebrio molitor L. flours were used. A 30% share of insect flour in the bars resulted in significantly greater antioxidant activity (TPC increased from 190.19 for standard bars to 309.45 mg catechin/100 g for bars with 30% addition of cricket flour). Insect flour contributed significantly to an increase in 2,5-dihydrobenzoic acid (from 0.12 for bars with a 15% share of buffalo worm flour to 0.44 mg/100 g in the case of bars with a 30% share of cricket flour) and chlorogenic acid in all bars (from 0.58 for bars with a 15% share of cricket flour to 3.28 mg/100 g for bars with a 30% addition of buffalo worm flour), compared to the standard. The highest content of tocopherols was found in bars with cricket flour, compared to standard bars (43.57 and 24.06 mg/100 g of fat, respectively). The dominant sterol in bars enriched with insect powder was cholesterol. The highest amount of it was found in cricket bars, and the lowest in mealworm bars (64.16 and 21.62 mg/100 g of fat, respectively). The enrichment of nut bars with insect flours raises the levels of valuable phytosterols in the final product. The addition of edible insect flours reduced the perception of most sensory attributes of the bars, compared to the standard bar.

Alternative Protein Sources and Novel Foods: Benefits, Food Applications and Safety Issues

The increasing size of the human population and the shortage of highly valuable proteinaceous ingredients has prompted the international community to scout for new, sustainable, and natural protein resources from invertebrates (e.g., insects) and underutilized legume crops, unexploited terrestrial and aquatic weeds, and fungi. Insect proteins are known for their nutritional value, being rich in proteins with a good balance of essential amino acids and being a valuable source of essential fatty acids and trace elements. Unconventional legume crops were found rich in nutritional, phytochemical, and therapeutic properties, showing excellent abilities to survive extreme environmental conditions. This review evaluates the recent state of underutilized legume crops, aquatic weeds, fungi, and insects intended as alternative protein sources, from ingredient production to their incorporation in food products, including their food formulations and the functional characteristics of alternative plant-based proteins and edible insect proteins as novel foods. Emphasis is also placed on safety issues due to the presence of anti-nutritional factors and allergenic proteins in insects and/or underutilized legumes. The functional and biological activities of protein hydrolysates from different protein sources are reviewed, along with bioactive peptides displaying antihypertensive, antioxidant, antidiabetic, and/or antimicrobial activity. Due to the healthy properties of these foods for the high abundance of bioactive peptides and phytochemicals, more consumers are expected to turn to vegetarianism or veganism in the future, and the increasing demand for such products will be a challenge for the future.

Insect biorefinery: A circular economy concept for biowaste conversion to value-added products

With rapid growing world population and increasing demand for natural resources, the production of sufficient food, feed for protein and fat sources and sustainable energy presents a food insecurity challenge globally. Insect biorefinery is a concept of using insect as a tool to convert biomass waste into energy and other beneficial products with concomitant remediation of the organic components. The exploitation of insects and its bioproducts have becoming more popular in recent years. This review article presents a summary of the current trend of insect-based industry and the potential organic wastes for insect bioconversion and biorefinery. Numerous biotechnological products obtained from insect biorefinery such as biofertilizer, animal feeds, edible foods, biopolymer, bioenzymes and biodiesel are discussed in the subsequent sections. Insect biorefinery serves as a promising sustainable approach for waste management while producing valuable bioproducts feasible to achieve circular bioeconomy.

Nutritional Value of Silkworm Pupae (Bombyx mori) with Emphases on Fatty Acids Profile and Their Potential Applications for Humans and Animals

Bombyx mori is an ideal lepidopteran species representative of many scientific studies, a model of studies for medicine and a significant insect from an ecological standpoint. This review was performed to summarize the fatty acids (FA) composition of silkworm pupae (SP) that are associated with other important compounds that could add value to SP, diversifying the ways of valorization. The proposal to complete plant-based feeds with insect-based feeds represents a viable option to beneficially impact human and animal health and the environment. The quality and quantity of fats consumed significantly impact the aetiology of certain diseases. The key compounds of fat named essential FA (EFA) substantially influence the prevention and treatment of several diseases through their nutraceutical functions. Due to its excellent profile in nutrients such as protein and fat, amino acids and fatty acids composition, SP has become an important alternative feed ingredient and source of EFA. SP is a by-product that was discarded in large quantities. Following the need to act to improve human health and reduce climate change impact, many researchers focused on studying SP applications in the medical and agricultural industries. Several authors noticed an improvement in the health markers by using SP. The feed cost for the animal was reduced with economic implications. Minimization of environmental impact was recorded. Few precautions were recommended regarding SP use, although they should not be ignored. The composition of SP and its potential for use in various industries provides us with persuasive arguments for continuing to develop the sericulture industry.

Evaluation of full-fatted and hydrolysate mealworm (Tenebrio molitor) larvae as a substitute for spray-dried plasma protein diet in weaning pigs

The goal of this experiment was to examine the effect of dietary inclusion of full-fatted mealworm larvae (FFML) or hydrolysate mealworm larvae (HML) (Tenebrio molitor) as a substitute for spray-dried plasma protein (SDPP) as a protein source on the performance and immune status of nursery pigs. A total of 150 crossbred piglets (6.48 ± 0.01 kg) were randomly allocated to 1 of 3 dietary groups in two feeding phases: phase 1 (Days 0-14) and phase 2 (Days 15-35). Each treatment had 10 replicates with 5 pigs per replicate. The nutritious diets were: Phase 1: SDPP-CON (control-basal diet) + 6% SDPP diet; FFML-CON + 3% SDPP and 3% FFML diet; HML-CON + 3% SDPP and 3% HML diet. Phase 2: SDPP-CON (basal diet) + 3% SDPP diet; FFML-CON + 3% FFML diet; HML-CON + 3% HML diet. The inclusion of FFML or HML diet did not show significant difference but had a comparable effect as that of standard control diet containing SDPP on the growth performance, nutrient digestibility and faecal score throughout the trial. In comparison to pigs fed SDPP diet, pigs fed FFML and HML diets had similar and/or higher (p < 0.05) serum immunoglobulin (IgA and IgG) concentration at the end of phase 1 and 2. The result of the present study indictes that SDPP would be partially or fully replaced with FFML or HML to suit weaning pigs diet.

The Review of Cooking, Drying, and Green Extraction Methods on General Nutritional Properties of Mealworms and Locusts

The processing of edible insects as an alternative source of nutrition may be a key driver in the development of a sustainable food and feed system. This review will study two industrial types of insects-mealworms and locusts-and summarize evidence related to the impact of processing on their micro- and macronutritional characteristics. The focus will be on their potential use as food for human consumption as opposed to animal feed. Literature has indicated that these two insects have the potential to provide protein and fat qualities comparable to or better than traditional mammalian sources. For example, mealworms-the larval form of the yellow mealworm beetlepossess a higher fat content, while adult locusts are rich in fibers, especially chitin. However, due to the different matrix and nutrient compositions, the processing of mealworms or locusts at a commercial scale needs to be tailored to minimize nutritional loss and maximize cost efficiency. The stages of preprocessing, cooking, drying, and extraction are the most critical control points for nutritional preservation. Thermal cooking applications such as microwave technology have demonstrated promising results, but the generation of heat may contribute to a certain nutritional loss. In an industrial context, drying using freeze dry is the preferred choice due to its uniformity, but it can be costly while increasing lipid peroxidation. During the extraction of nutrients, the use of green emerging technologies such as high hydrostatic pressure, pulsed electric field, and ultrasound may provide an alternative method to enhance nutrient preservation.

Graphical Abstract

Integrative single-cell characterization of frugivory adaptations in the bat kidney and pancreas

Frugivory evolved multiple times in mammals, including bats. However, the cellular and molecular components driving it remain largely unknown. Here, we used integrative single-cell sequencing on insectivorous and frugivorous bat kidneys and pancreases and identified key cell population, gene expression and regulatory element differences associated with frugivorous adaptation that also relate to human disease, particularly diabetes. We found an increase in collecting duct cells and differentially active genes and regulatory elements involved in fluid and electrolyte balance in the frugivore kidney. In the frugivorous pancreas, we observed an increase in endocrine and a decrease in exocrine cells and differences in genes and regulatory elements involved in insulin regulation. Combined, our work provides novel insights into frugivorous adaptation that also could be leveraged for therapeutic purposes.

Quality of Tenebrio molitor Powders: Effects of Four Processes on Microbiological Quality and Physicochemical Factors

Tenebrio molitor, the first edible insect approved as a novel food in the EU, is a promising candidate for alternative protein sources, implementing circular and sustainable production systems. This study aims to determine the microbiological quality and physicochemical properties of mealworm powders obtained by four different processing pathways. Contents of dry matter, protein, fat, ash, water activity (aw) and a range of microbial counts were measured and analyzed by one-way ANOVA with Tukey's test. Results showed small differences in the proximate composition of the powder samples (protein 55.62-57.90% and fat 23.63-28.21% of dry matter, DM), except for the one that underwent a defatting step (protein 70.04% and fat 16.84%), p < 0.05. A level of water activity of less than 0.2 was reached for all pathways. Fresh mealworm samples had high total aerobic counts (8.4 log CFU/g) but were free of foodborne pathogens. Heat treatments applied during transformation were sufficient to kill vegetative cells (reduction of 2.8-5.1 log CFU/g) rather than bacterial endospores (reduction of 0.3-1.8 log CFU/g). Results were confirmed by predictive microbiology. This study validated the efficacy of a boiling step as critical control points (CCPs) of insect powder processing, providing primary data for the implementation of HACCP plans.

Factors Affecting the Nutritional, Health, and Technological Quality of Durum Wheat for Pasta-Making: A Systematic Literature Review

Durum wheat is one of the most important food sources in the world, playing a key role in human nutrition, as well as in the economy of the different countries in which its production areas are concentrated. Its grain also represents a staple and highly versatile ingredient in the development of health foods. Nonetheless, the aspects determining durum wheat's health quality and their interactions are many, complex, and not entirely known. Therefore, the present systematic literature review aims at advancing the understanding of the relationships among nutritional, health, and technological properties of durum wheat grain, semolina, and pasta, by evaluating the factors that, either positively or negatively, can affect the quality of the products. Scopus, Science Direct, and Web of Science databases were systematically searched utilising sets of keywords following the PRISMA guidelines, and the relevant results of the definitive 154 eligible studies were presented and discussed. Thus, the review identified the most promising strategies to improve durum wheat quality and highlighted the importance of adopting multidisciplinary approaches for such purposes.

Is Generation Z Ready to Engage in Entomophagy? A Segmentation Analysis Study

This study examines the behavior and attitudes of adult Generation Z cohort members in relation to entomophagy. Specifically, it explores their familiarity with insect consumption, prior experience, and willingness to consume certain insect-based foods and drinks. Lastly, the Z cohort is segmented based on their behavior and attitudes. Through online quantitative research, a valid sample of 742 questionnaires was collected. Data analysis included descriptive statistics, reliability analysis, factor, hierarchical cluster, and K-means cluster analysis, as well as chi-square tests. Results revealed that 41.4% are familiar with what insect consumption is, and no one had previously engaged in entomophagy. The insect-based food that the Z cohort is most willing to try is bakery products containing insect flour. The 88.5% of the Z cohort is not willing to replace meat protein with insect protein, and 20.4% are interested in obtaining more information about entomophagy. Moreover, 6.3% of the Z cohort is "willing" to participate in sensory tests, but when contact information was requested, only one factual name with phone number was provided. Segmentation of the Z cohort's behavior was performed based on eight variables and four segments were identified: the "Future potential insect consumers" (29.1%), the "Rejecters" (26.7%), the "Disgusted, prefer to starve" (22.2%), and the "Inconsistent" (22.0%). Overall, the Z cohort is not food neophobic, but is unwilling to engage in entomophagy. Communication strategies are suggested to increase awareness and provide information about entomophagy and its benefits.

Nutritional Compositions of Aquatic Insects Living in Rice Fields, with a Particular Focus on Odonate Larvae

Although the human consumption of aquatic insects is prevalent in many regions, the nutritional composition of the insects has not been comprehensively determined. The proximate composition of Pantala sp. was shown to be a good source of protein (49.45 ± 0.32 g/100 g DW), as well as of minerals such as sodium, calcium, potassium, phosphorus, zinc, and iron. All nine essential amino acids are present in this species, with valine being the most abundant. The major fatty acids are palmitic acid (1.19 ± 0.02 g/100 g DW), oleic acid (0.63 ± 0.02 g/100 g DW), and linoleic acid (0.55 ± 0.01 g/100 g DW). Lead (Pb), arsenic (As), and cadmium (Cd) showed a value of 0.18 ± 0.01 mg·kg^-1, 3.51 ± 0.12 mg·kg^-1, and 0.17 ± 0.00 mg·kg^-1, respectively. Furthermore, microplastic (MP) contamination in odonate larvae (419 individuals belonging to three identified families) was found in varying shapes, e.g., fibers, fragments, and rods. FTIR analysis revealed the following MP polymers, polyethylene terephthalate, polyvinyl acetate, bis(2-ethylhexyl), polybutadiene, poly(methyl methacrylate-co-methacrylic acid); P(MMA-co-MA), poly(ethylene glycol) tetrahydrofurfuryl ether, poly(acrylonitrile-co-butadiene), and polypropylene glycol. The results of this work could be a nutritional reference for food security and the risk of eating insects.

Riboflavin as One of Possible Components of Keroplatus (Insecta: Diptera: Keroplatidae) Fungus Gnat Bioluminescence

Abstract

Keroplatus is a genus of fungus gnats family Keroplatidae (Diptera, Bibionomorpha). Larvae of some species emit a constant blue light from the body. The bioluminescence of Keroplatidae is one of the least studied of all terrestrial insects and very few facts are known to date of its biology and biochemistry. Here we report the high level of riboflavin in Keroplatus testaceus larvae, a fluorescent compound that might be relative to its bioluminescent system. We suppose that riboflavin may play a role in Keroplatus spp. bioluminescence.

Environmental effects of harvesting some Mexican wild edible insects: An overview

Most traditional edible insects are collected from the forest and agricultural fields, where they are considered pests. However, their importance goes beyond this. They also have an ecological role and potential to be an emerging alternative source of high-quality nutrients that can help satisfy the growing food demand for the human population. Agricultural insect pests are a healthy food source during the harvesting season in many tropical countries. In Mexico, wild insects such as chicatana (queen of flying leaf-cutter ant, Atta mexicana Smith, 1,858; Hymenoptera: Formicidae), chapulín (grasshopper, Pyrgomorphidae), chinicuil (agave red worm, Comadia redtenbacheri Hammerschmidt, 1,848: Lepidoptera, Cossidae), and meocuil (agave white worm, Aegiale hesperiaris Walker 1,856, Lepidoptera, Hesperiidae) are seasonally collected from the agricultural land and forest for food and medicine. Thus, their consumption might be regarded as support for biological plague control. However, in most countries (Mexico included), there is a lack of legislation about edible insects from harvesting to sacrifice and even their main safety aspects. So then, this research aims to provide an updated assessment of the potential use of agricultural pest insects as a sustainable alternative for food, considering current international legislative and ethical concerns about harvesting and consuming wild edible insects, focusing on some of the wild edible pest insects in Mexico.

Beyond Human Nutrition of Edible Insects: Health Benefits and Safety Aspects

Nowadays, edible insects are considered an outstanding source of nutrients, primarily because they contain high-quality protein, amino acids, and vitamins. Insects are considered a promising alternative protein source towards alleviating future global food shortage problems due to their production considered as being more sustainable by using less agricultural land and water, as well as releasing a smaller amount of greenhouse gas emissions. However, other important aspects to consider about the consumption of edible insects include their health benefits and some safety aspects, which has been relatively overlooked. In this sense, edible insects contain bioactive compounds that can provide diverse bioactivities, such as antioxidant, antihypertensive, anti-inflammatory, antimicrobial, and immunomodulatory with a positive impact on human health. On the other hand, edible insects are a nutrient-rich food that can provide a perfect growth medium for diverse microorganisms, as well as possess some anti-nutritive factors. These two main aspects could represent food safety concerns for consumers. In this context, recent scientific evidence indicates that preservation methods, mainly thermal treatments, utilized in the cooking or processing of edible insects decreased the microbial levels and anti-nutritive factors, which suggests that edible insects do not represent a critical biological risk to humans. Besides, edible insects could have a positive effect on gut microbiota, either by their pre-biotic effect or their antimicrobial activity towards pathogens. Thus, this review is focused on studies related to the health benefits of edible insects and their isolated components, as well as discussion about potential issues related to their microbial content and anti-nutritive factors; this review will provide a synopsis on whether edible insects may be considered safe for human consumption.

Nutritional Composition of Some Commonly Available Aquatic Edible Insects of Assam, India

The nutritive value of five edible aquatic insects of Assam-Hemipterans; water bug (Diplonychus rusticus Fabricius) family belostomatidae; giant water bug (Lethocerus indicus Lepeletier and Serville) family belostomatidae; water scorpion (Laccotrephes sp.) family nepidae, water stick (Ranatra sp.) family nepidae; Coleopterans diving beetle (Cybister sp.) family dytiscidae-based on their proximate and elemental composition, antioxidant and antinutritional properties were assessed by using standard methods of analysis. Analytical studies revealed that the selected aquatic insect species have high nutritive value and are rich sources of protein (50.03 to 57.67%) and other nutrients (fat, carbohydrate and crude fiber, etc.) along with superior energy contents (331.98 to 506.38 kJ/100 g). The aquatic insect species also contained appreciable amounts of major and trace dietary elements. Phenol and flavonoid contents reflect its high antioxidant activity (80.82 to 91.47% DPPH inhibition). Tannin (18.50 to 60.76 mg tannic acid equivalent/100 g), phytic acid (11.72 to 97.30 mg/100 g) and oxalic acid (2.93 to 5.34 mg/100 g) as antinutritional compounds were registered below the toxic level (0.52% or 520 mg/100 g). The present findings indicate that the selected aquatic insect species can be considered as ideal candidates for exploration as food and feed to ensure nutritional and livelihood security of this region.

The Antibacterial Activity of Egyptian Wasp Chitosan-Based Nanoparticles against Important Antibiotic-Resistant Pathogens

The current work discusses the production and characterization of new biodegradable nanoparticles for biomedical applications based on insect chitosan. Chitosan has numerous features due to the presence of primary amine groups in repeating units, such as antibacterial and anticancer activities. When polyanion tripolyphosphate is added to chitosan, it creates nanoparticles with higher antibacterial activity than the original chitosan. In this study, the ionic gelation technique was used to make wasp chitosan nanoparticles (WCSNPs) in which TEM and FTIR were used to investigate the physicochemical properties of the nanoparticles. In addition, the antibacterial activities of chitosan nanoparticles against extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa were evaluated. The extracted wasp chitosan exhibited high solubility in acetic acid and met all standard criteria of all characterization testes for nanoparticles; the zeta potential indicated stable WCSNPs capable of binding to cellular membrane and increasing the cellular uptake. The produced WCSNPs showed growth inhibition activity against all tested strains, and the bacterial count was lower than the initial count. The inhibition percent of WCSNPs showed that the lowest concentration of WCSNPs was found to be effective against tested strains. WCSNPs’ antibacterial activity implies that they could be used as novel, highly effective antibacterial agents in a variety of biological applications requiring antibacterial characteristics.

Edible Insects for Humans and Animals: Nutritional Composition and an Option for Mitigating Environmental Damage

Every day, there is an increase in environmental damage on the planet regarding human action. One of the causes is food production. Edible insects are presented as an option to mitigate the environmental damage generated by the production of conventional food for humans and animals. The objective of this study was to investigate the main nutritional aspects of insects and how they can provide a nutritional and sustainable alternative to the planet. As the main results, the nine orders of insects that are most consumed on the planet are presented: Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Isoptera, Lepidoptera, Odonata, and Orthoptera. Their main macro- and micronutrient aspects as well as their bioavailable and bioaccessibility proteins and essential amino acids, monounsaturated fatty acids, minerals, vitamins, and fiber (chitin) are also explored. Additionally, some of the species that are used for animal food processing and the possible risks that insects can present when used as food are discussed. With this, edible insects are established as a real option to mitigate climate change being an important nutritional source for the development of food for humans and animals.

Will It Cricket? Product Development and Evaluation of Cricket (Acheta domesticus) Powder Replacement in Sausage, Pasta, and Brownies

Insect powders used in food products may lower the overall quality when compared to conventional counterparts. This preliminary study was used to develop and evaluate insect-based food products and to utilize them in a future consumer test. Pork sausage, dried pasta, and chocolate brownie formulations were developed to either contain NO cricket powder (Control) or have cricket powder (CP). The products were evaluated for proximate composition and product-dependent parameters. The protein content increased in the CP pasta and brownies (p < 0.05) while no changes were found in the sausage (p > 0.05). Fat content increased in both the CP pasta and brownies while it decreased in the CP sausage (p < 0.05). The CP sausage had a higher carbohydrate content than the Control (p < 0.05). Overall, this may be attributed to cricket powder being high in protein and fat while also containing dietary fiber. Cricket powder replacement may lead to noticeable color differences by increasing green and blue coloring in sausage and pasta (p < 0.05). Changes in textural properties (p < 0.05) may be attributed to cricket powder affecting protein solubility and emulsion stability in sausage while gluten formation may be interfered with in the brownies. Overall, cricket powder replacement had improved nutritional content with minor changes in quality parameters.

Human Consumption of Insects in Sub-Saharan Africa: Lepidoptera and Potential Species for Breeding

There are 472 edible insect species in sub-Saharan Africa, of which 31% are Lepidoptera. Wild harvesting is still the main source of supply for these prized species to this day, with some harvesting techniques negatively impacting the environment. The successful production of edible caterpillars requires the appropriate and efficient implementation of husbandry techniques and practices. In this review, we present current literature on edible caterpillars. We provide a general overview of their life history, nutritional composition, and availability associated with specific host plants, with emphasis on semi-domestication and rearing practices that should replace wild harvest. Based on the assimilated information, a proposal of potential species for farming is provided, with details on key characteristics of development cycles to promote the establishment and development of sustainable farms of edible caterpillars at small and large scales. Such advances would contribute toward reducing anthropological pressure related to the exploitation of these food resources, as well as the environmental footprint of this widespread practice.

Development of a Quantitative UPLC-ESI/MS Method for the Simultaneous Determination of the Chitin and Protein Content in Insects

In a context where the commercial and nutritional interest in insect chitin is always increasing, an accurate and precise method to quantify this biopolymer, especially in food/feed, is required. In addition, quantification of insect crude protein through nitrogen determination is normally overestimated due to the presence of chitin. In this work, for the first time, an RP-UPLC-ESI/MS method for the simultaneous quantification in insects of chitin, as glucosamine (GlcN), and protein, as total amino acids, is presented. The method is based on acid hydrolysis and derivatization of amino acids and GlcN with the AccQ Tag reagent. Method was optimized and validated in terms of linearity, LOD and LOQ, intraday and inter-day repeatability, and accuracy. A hydrolysed commercial chitin was selected as reference standard for calibration. The instrumental LOD and LOQ correspond respectively to a concentration of 0.00068 mM and 0.00204 mM. The intraday precision satisfied the Horwitz ratio. Data from inter-day precision showed the necessity to perform the analysis within 1 week utilizing standard calibration solutions freshly prepared. A matrix effect was observed, which suggested the necessity to use an internal calibration curve or to work in a particular concentration range of GlcN. The chitin and protein content in black soldier fly (Hermetia illucens) and lesser mealworm (Alphitobius diaperinus) were found in agreement with results obtained by independent methods. The optimized method was also tested on two different commercial food supplements, suggesting its applicability on a wide range of matrices. This newly developed method proved to be simple, more accurate, and faster if compared to methods which separately analyse chitin and protein content.

Recent Insight on Edible Insect Protein: Extraction, Functional Properties, Allergenicity, Bioactivity, and Applications

Due to the recent increase in the human population and the associated shortage of protein resources, it is necessary to find new, sustainable, and natural protein resources from invertebrates (such as insects) and underutilized plants. In most cases, compared to plants (e.g., grains and legumes) and animals (e.g., fish, beef, chicken, lamb, and pork), insect proteins are high in quality in terms of their nutritional value, total protein content, and essential amino acid composition. This review evaluates the recent state of insects as an alternative protein source from production to application; more specifically, it introduces in detail the latest advances in the protein extraction process. As an alternative source of protein in food formulations, the functional characteristics of edible insect protein are comprehensively presented, and the risk of allergy associated with insect protein is also discussed. The biological activity of protein hydrolyzates from different species of insects (Bombyx mori, Hermetia illucens, Acheta domesticus, Tenebrio molitor) are also reviewed, and the hydrolysates (bioactive peptides) are found to have either antihypertensive, antioxidant, antidiabetic, and antimicrobial activity. Finally, the use of edible insect protein in various food applications is presented.

A Comprehensive Review of the Importance of Selected Trace Elements Present in Edible Insects

This review is intended to provide recent published information on trace elements from edible insects from various environments. Recently, insects are gaining popularity as food proteins in developing countries and press higher demand for edible insects since they may provide similar nutritional value as meat. Insects have been part of the human diet in the world for decades and at least 1900 insect species are considered edible. Furthermore, insects play a crucial role in socioeconomic by contributing to the world's food security as well as eradicating poverty in rural communities. Generally, edible insects are considered a readily available source of proteins, carbohydrates, and chitin. They also contain considerable amounts of trace elements such as iron, zinc, copper, and manganese. It has been observed that there is a great variation between mineral contents found in insects of the same or different species. Knowledge and comprehensive understanding of trace element contents of edible insects are crucial to fully maximise their utilisation in diets and prevent mineral deficiency in human beings and animals. However, most of the research on insects has focused on the nutritional contents of insects with less attention given to other nutritional components such as minerals and trace elements. The available data on trace elements from edible insects as food is limited and makes it difficult to draw estimations for the nutrient intake of humans and animals. Therefore, this review aimed to provide comprehensive information on availability of iron, zinc, copper, and manganese from selected edible insects, functions, and deficiencies in both humans and animals.

Honey Bee (Apis mellifera L.) Broods: Composition, Technology and Gastronomic Applicability

Honey bee broods (larvae and pupae) can be consumed as human food, offering a rich nutritional value. Therefore, the objective of this work was to present an overview of the nutritional value of the honey bee brood and its gastronomic potential. The results indicated that honey bee broods are rich in protein (including essential amino acids), fat (essentially saturated and monounsaturated fatty acids), carbohydrates, vitamin C and those of the B complex, and minerals such as potassium, magnesium, calcium, and phosphorous. The results further highlight some variability according to the stage of development, with increasing content of fat and protein and decreasing carbohydrates from the larval to the pupal stages. The production of the honey bee brood in the hive, as well as its removal, can impact the wellbeing of the hive. This limits the production potential of the brood aimed at application for gastronomic purposes. The consumption and purchase of honey bee broods as food may be accessible in specialised markets where, for example, ethnic communities consume this type of food. However, in some markets, insects or products produced from insects are not readily accepted because of neophobia and disgust. The role of culinary chefs allied to traditional ways of preparing culinary dishes that include honey bee broods are relevant to motivate more people in western societies to consume of these types of food products.

Growth performance and intestinal morphometric features of broiler chickens fed on dietary inclusion of yellow mealworm (Tenebrio molitor) larvae powder

BACKGROUND

Climate change and the lack of conventional feed ingredients have made edible insects a highly nutritious alternative to feed production. The use of insects as food may help solve socio-economic and environmental problems around the world and be in line with the United Nations Sustainable Development Goals.

OBJECTIVE

In this study, the growth performance and intestinal morphology of broiler chickens were evaluated under the influence of adding different levels of Tenebrio molitor larvae meal (TM meal) to their diets.

METHODS

One hundred and eighty one-day-old broiler chickens were divided into three treatments and five replications (12 chickens/pen). The experimental diets included a control diet and treatments containing 2.5% and 5% TM meal, which were fed to birds in the starter (0-10 days) and grower (11-25 days) stages, and during the final period (26-42 days), all birds were fed a regular finisher diet.

RESULTS

The results showed that the diet containing TM meal had no remarkable effect on the mortality rate and feed intake of broilers (p > 0.05). In the starter period, the addition of 2.5% TM meal to broilers' diet increased body weight gain than the control group (p ≤ 0.05). Also, the use of 2.5% TM meal in the starter period showed a significant effect on reducing the feed conversion ratio, compared to the birds fed by the control diet (p ≤ 0.05). Besides, the height of the villus, the depth of the crypt and their ratio were not altered among the different treatments (p > 0.05).

CONCLUSIONS

Overall, it can be concluded that TM meal could improve growth performance in the starter period and had no negative effects on broilers' performance and intestinal morphology in all the periods of the experiment.

Nutritional composition and sensory Properties of wheat muffins enriched with Gonimbrasia zambesina, walker caterpillar flour

Sub-Saharan Africa still bears the greatest forms of malnutrition. Attention is shifting to the use of edible insects in forms which are acceptable to people irrespective of their social status and level of civilization in efforts to alleviate protein malnutrition. Gonimbrasia zambesina (Lepidoptera: Saturniidae) caterpillars emerge seasonally in the coastal part of Kenya and despite their rich nutritional profile, their consumption is low. This study was thus undertaken to evaluate the effect of substituting wheat flour with G. zambesina caterpillar flour at 0%, 5%, 10%, 15% and 20% substitution levels on the nutritional composition and sensory properties of wheat muffins. Substituting wheat flour with G. zambesina caterpillar flour resulted in significantly high protein, fat and fibre contents of enriched wheat muffins. There was also an increasing trend in the ash, minerals and tocopherol content. Invitro protein digestibility significantly decreased from 10 to 20% substitution levels. There was a significant difference (p < 0.05) in the carbohydrate contents of enriched wheat muffins. The sensory scores for colour, texture, aroma and the overall acceptability of wheat muffins decreased with increasing substitution levels. At 10% substitution level, wheat muffins had significantly higher nutritional content than control wheat muffins (0%) and were comparable to muffins enriched with 5% G. zambesina caterpillar flour in terms of overall acceptability. Thus, enriching wheat muffins with G. zambesina caterpillar flour at 10% substitution level has the potential to contribute to improved protein nutrition since they have a higher protein content than the control wheat muffin and are 88.8% digestible (in vitro).

Cellular lipids and protein alteration during biodegradation of expanded polystyrene by mealworm larvae under different feeding conditions

The present study reports the biodegradation of polystyrene (PS) by mealworm (Tenebrio molitor) following different feeding regimes. Changes in lipids and protein were studied to evaluate possible differences in the growth and metabolic pathways of the insects depending on the diets. Thermo-gravimetric analysis of the excretions (frass) revealed a decrease in the molecular mass of the PS polymers. The insects' biomass contained less protein when PS was part of the diet, suggesting that the insects undergo a certain level of stress compared to control diets. The frass also contained lower amount of nitrogen content compared to that from insects fed a control diet. NH₄⁺ and other cations involved in biochemical processes were also measured in insects' frass, including potassium, sodium, magnesium, and calcium, combined with a small pH change. The decrease in the mineral content of the frass was attributed to increased cellular activity in PS-fed insects. A higher amount of ceramides and cardiolipins, biomarkers of apoptosis, were also found in association with PS consumption. It was concluded that the insects could metabolize PS, but this caused an increase in its stress levels.

In Vitro Crude Protein Digestibility of Insects: A Review

The high protein content of insects has been widely studied. They can be a good food alternative, and therefore it is important to study the effect of digestion on their protein. This review examines the different in vitro protein digestibility methodologies used in the study of different edible insects in articles published up to 2021. The most important variables to be taken into account in in vitro hydrolysis are the following: phases (oral, gastric and intestinal), enzymes, incubation time and temperature, method of quantification of protein hydrolysis and sample preprocessing. Insects have high digestibility data, which can increase or decrease depending on the processing of the insect prior to digestion, so it is important to investigate which processing methods improve digestibility. The most commonly used methods are gut extraction, different methods of slaughtering (freezing or blanching), obtaining protein isolates, defatting, thermal processing (drying or cooking) and extrusion. Some limitations have been encountered in discussing the results due to the diversity of methodologies used for digestion and digestibility calculation. In addition, articles evaluating the effect of insect processing are very limited. It is concluded that there is a need for the standardisation of in vitro hydrolysis protocols and their quantification to facilitate comparisons in future research.

A Non-Destructive High-Speed Procedure to Obtain DNA Barcodes from Soft-Bodied Insect Samples with a Focus on the Dipteran Section of Schizophora

While the need for biodiversity research is growing, paradoxically, global taxonomical expertise is decreasing as a result of the neglected funding for young academics in taxonomy. Non-destructive approaches for DNA barcoding are necessary for a more efficient use of this dwindling expertise to fill gaps, and identify incorrect entries in sequence databases like BOLD or GenBank. They are efficient because morphological re-examination of species vouchers is still possible post-DNA barcoding. Non-destructive approaches for Diptera with a comprehensive species representation or the consideration of diagnostic fragile morphological characters are missing. Additionally, most non-destructive approaches combine a time intensive and non-destructive digestion step with common DNA extraction methods, such as commercial kits or CTAB DNA isolation. We circumvented those approaches and combined a modified non-destructive TE buffer high-speed DNA extraction, with a PCR inhibitor-resistant PCR reaction system, to a non-destructive DNA barcoding procedure for fresh and frozen samples of the Schizophora (Diptera). This method avoids morphological impairment and the application of harmful chemicals, is cost and time effective, restricts the need for laboratory equipment to a minimum, and prevents cross-contamination risk during DNA isolation. Moreover, the study indicates that the presented non-destructive DNA barcoding procedure is transferable to other soft-bodied insects. We suggest that PCR inhibitor-resistant master mixes enable the development of new—and the modification of existing—non-destructive approaches with the avoidance of further DNA template cleaning.

Fate of Salmonella enterica Typhimurium and Listeria monocytogenes in Black Soldier Fly (Hermetia illucens) Larvae Reared on Two Artificial Diets

Ensuring food security is one of the main challenges facing the world over the next 30 years. There is, thus, an urgent need to significantly increase the supply of sustainable protein that can be transformed into animal feed. Proteins from insects offer a valuable alternative. This article presents the results of challenge tests conducted to investigate the dynamics of the microbial load of Salmonella enterica Typhimurium and Listeria monocytogenes in black soldier fly (Hermetia illucens) larvae grown on contaminated substrates. Four separate challenge tests were performed on two substrates: the Gainesville diet and a homemade diet. The challenge test procedure was carried out in accordance with ISO/DIS 20976-2 (under development). The results of this study show that, when grown on contaminated substrates, BSF larvae do not eliminate Salmonella Typhimurium or L. monocytogenes, but can reduce their microbial load. Sanitation processes downstream of the breeding of BSF larvae are, however, required to reduce the microbiological risks of this novel food.

Nidus vespae Built by an Invasive Alien Hornet, Vespa velutina nigrithorax, Inhibits Adipose Tissue Expansion in High-Fat Diet-Induced Obese Mice

Nidus vespae, commonly known as the wasp nest, has antioxidative, anti-inflammatory, antimicrobial, and antitumor properties. However, the anti-obesity effects of Nidus vespae extract (NV) have not yet been reported. This study aimed to elucidate the potential anti-obesity effects of NV in vivo and in vitro, using a high-fat diet (HFD)-induced obese mouse model and 3T3-L1 adipocytes, respectively. NV administration to HFD-induced obese mice significantly decreased the mass and plasma lipid content of adipose tissues. Uncoupling protein-1 expression was significantly higher in the inguinal white adipose tissues of NV-treated mice than in those of HFD-fed mice. Furthermore, we found that NV inhibited the differentiation and intracellular lipid accumulation of 3T3-L1 adipocytes by regulating the insulin signaling cascade, including protein kinase B, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer binding protein alpha, and adiponectin. These findings suggest that NV may exhibit therapeutic effects against obesity by suppressing adipose tissue expansion and preadipocyte differentiation, thereby providing critical information for the development of new drugs for disease prevention and treatment. To our knowledge, this study provides the first evidence of the anti-obesity effects of NV.

Edible Insects in Latin America: A Sustainable Alternative for Our Food Security

Nowadays, the food industry faces paramount challenges in different areas, since worldwide consumers are increasing every day, and at the same time, they are demanding new convenient products. Recent studies show that the current food production system is unsustainable over time and therefore is necessary to create new alternatives of production. New food trends are focused on the consumption of natural products, that have an eco-friendly production approach, and a beneficial nutritional profile for the consumer’s health. Hence, products are being created to not only have good organoleptic characteristics, but also to contain a wide variety of micro and macronutrients, and to be sustainable within their production. For this reason, the use of raw materials that satisfy the needs previously mentioned is being implemented. For instance, the use of insects as raw material, because they have a high protein content comparable to animal-based foods. Specifically, ants and crickets can contain between 9 and 77% protein of dry weight, while beef contains between 25 and 28%. On the other hand, insects present an ease and sustainable production system, compared to livestock farming, since some of them feed with food waste generated by humans. In addition, require less food for their upbringing; insects can convert 2 kg of feed into 1 kg of insect mass, while cattle use 8 kg of feed to produce 1 kg of body weight. On the other hand, there is evidence that insects produce fewer greenhouse gases during their production, for example, pigs produce between 10 and 100 times more greenhouse gases per kg of weight. United States, Mexico, Chile, Peru, and Argentina have begun to develop and consume these products; thus, promoting different and new ventures. Large-scale production of insect-based food products could help solve or even prevent the looming food problem and contribute to the sustainable development goals set by the United Nations. Thus, the aim of this review work was to compile and investigate the edible insect’s alternatives in Latin America, as well as the commercially available or potential derivative products. We discussed the nutritional value of edible insects, and how they could contribute to food security.

Does space matter? Estimation and evaluation of required space for commercial mass culture of grasshoppers (Acridoidea: Orthoptera)

A space-dependent mortality assay was performed on thirty-one short-horned adult grasshopper species (Acridoidea: Orthoptera) to estimate the space required for mass culture of acridids in captivity. Our findings show that acridids have a multidimensional mortality mode at different densities. The correlations between density and mortality of acridids in rearing units follow a sigmoidal curve. Acridid mortality significantly increases with individual numbers up to a threshold, after which mortality does not change even if the density increases further. A log-logistic sigmoidal function expresses the dose (density)-response (mortality) relationship in the majority of acridid species. Mortality of acridids at variable densities does not necessarily correspond with the body-mass of the insects, indicating that mortality is a body-mass independent event. As a ready reference, a utility chart has been prepared, providing the necessary conversion factor for estimating space for a given number of acridids. The present information will be helpful for commercial grasshopper farming in captivity.

Insects as Feed for Companion and Exotic Pets: A Current Trend

The objective of this review was to carry out a comprehensive investigation of the benefits of incorporating insects as a pet food ingredient and the implications this can have in determining a market demand for insect-based pet foods. Black soldier fly larvae (Hermetia illucens), mealworm larvae (Tenebrio molitor) and adult house crickets (Acheta domesticus) are currently used in pet food. These insects are widely fed to exotic pets, mainly in whole, live or dehydrated formats. They are also incorporated as meal or fat and are offered to cats and dogs as dry or wet food and treats. Scientific studies about the use of insects for dog and cat feed are scarce. Most studies are in dogs. Research shows that insect nutrients, mainly amino acids, have high digestibility, are beneficial to health, do not have any detrimental effect on the gut microbiota and are accepted by dogs. In several countries, insects are approved for use in pet food and commercialization has spread throughout the world. Pet owners are willing to try foods made with insect meal for their pets. In conclusion, the use of insects in pet food is a reality that is taking on more and more prominence.