Insect-Based Foods: A Comprehensive Review on Nutritional Benefits and Environmental Sustainability

In recent years, there has been a lot of interest in the nutritional profiles of various edible insect species as a source of protein that is both sustainable and alternative to traditional livestock. Among the many edible insects studied, mealworms (Tenebrio molitor), crickets (Acheta domesticus), grasshoppers, termites, silkworms, and other insects have the potential to provide nutrition to humans. To gain important insights into the potential role of these insects in addressing global food security challenges, researchers have attempted to thoroughly analyse their nutritional profiles. The nutritional composition of 236 edible insects has been published by the Food and Agriculture Organization, 2021. Arsenura armida, an edible insect, was incorporated into both non-defatted (NDF) and defatted flour (DF) to assess the nutritional profile, physical characteristics, and technological functions. It was discovered that NDF comprises 24.18 percent of lipids. The protein content of the flours was high, 20.36% in NDF and 46.89% in DF. The calculated molecular weight of the present soluble protein ranged from 12 to 94 kDa. Arsenura armida proved to be a good alternative to animal protein due to their functional and physical properties.¹² The Brazilian super worm Zophobas morio and the Jamaican field cricket Gryllus assimilis were discovered to contain 65.52% proteins, 21.80% lipids, 8.6% carbohydrates, 408% ashes, 40.64% lipids, 8.17% ashes, and 1.39% carbohydrates, respectively.

As per a study conducted in Nigeria, insects with high crude fat, protein, and vitamin content included Zonocercus variegatus, Macrotermes bellicosus, and Cirina forda. In comparison to the other two insects, Z. variegatus had higher concentrations of all necessary minerals except Na, K, and Fe. The study found that the three edible insects have adequate nutritional value, making them a viable substitute for other foods in the fight against nutritional deficiencies caused by malnutrition. Furthermore, the functional characteristics of these insects suggest that the food industry could use them to fortify and enrich human and animal diets.¹³ A study was conducted to know the effects of adding insect flour to bread on texture, color, dough rheology, chemical composition, and nutritional value. The fat percentage in insect flours varied from 8.37% to 29.64%, the protein content from 49.89% to 62.51%, and the total dietary fibre from 7.75% to 9.48%. Compared to wheat bread, 10% insect flour increased protein content and lysine amino acid levels significantly. Various insect species have different fatty acid profiles, with oleic, palmitic, and linoleic acids having high concentrations.

Acheta domesticus, commonly known as house cricket, is an edible insect with a high protein and nutrient content. It has the potential to be used in the food industry as it is safe, environmentally sustainable, and has a higher biological value. It is highly digestible and contains many fatty acids, including palmitic, stearic, oleic, and linoleic. Many traditional foods are deficient in vitamin B complex, necessitating the use of supplements, whereas house crickets are high in vitamin B complex. In general, house crickets are safe to eat and make cultivation effortless. They have the potential to be used in processed foods due to their solubility and ability to hold water and form gels and emulsions. Furthermore, incorporating its flour into products can boost nutritional value and represent a promising industry. For production, 92% of insects are gathered from the wild, whilst only a small amount is collected through international breeding.¹⁴ Acheta domesticus is regarded as a manageable species that can be reared domestically using low-cost farming techniques.^{15, 16} As the consumption of edible insects grows globally, food organizations must ensure their safety and lack of health risks.

In addition to eggs, shellfish, peanuts, and milk, insects also have the potential to cause allergic reactions. Every year, allergic reactions have been reported in China, where insects are commonly consumed. People with crustacean allergies are also susceptible to allergenicity in cricket-based products. As a result, shrimp-specific IgE levels can be used to reduce the risk of cricket consumption among allergic customers.¹⁷ Aside from antibodies, insect proteolysis or microwave heating during processing can produce hypoallergenic cricket protein ingredients or products.¹⁸

House crickets are high in protein, with dry weights ranging from 48.06 to 76.19g per 100g. They are high in micronutrients such as calcium, potassium, magnesium, phosphorus, sodium, iron, zinc, manganese, and copper. Not only minerals but also rich in vitamins like riboflavin, pantothenic acid, biotin, and folate which are usually the most deficient nutrients in humans.¹⁷  According to the National Institute of Health, the daily reference intake for children aged 4 to 8 is 19g/day, while for men and women over the age of 19 is 56 and 46g/day, respectively, which can be obtained by 100g of house cricket dry matter. The carbohydrate content ranges from 1.6 to 10.2g, while the fibre content ranges from 3.9 to 7.5 g/100 g DW.¹⁹ Chitin is the primary component that contributes to the high fibre content. Previously, the digestion of chitin in humans was questioned, but recently chitinases were discovered in human tissues, which could aid in the prevention of parasitic infections and allergic conditions.^17, Table 1

Gryllus assimilis, also known as black field cricket, is another insect that is regarded as a promising alternative to conventional proteins.²⁰ Studies have been conducted to assess the chemical and nutritional composition of this insect, and they show that they contribute as a substitute source of energy and protein.^{21, 22} Furthermore, it demonstrated that incorporating insect powder into products would result in higher protein quality. It was high in protein (57.36% to 67.97%), phosphorus (512.00-732 mg/100 g), copper (1.45-3.01 mg/100 g), iron (5.41-8.41 mg/100 g), zinc (11.62-25.57 mg/100 g), manganese (1.63-8.08 mg/100 g), magnesium (84.00-180.00 mg/100 g), and potassium (624.00-820.00 mg/100 g). Niacin levels range from 1.88 to 3.21 mg per 100 g. The proteins had high digestibility (84.48-92.53%) and increased solubility in alkaline pH nearly equal to 11 and lysine was identified as the limiting amino acid. The insect development stage influences nutritional content, amino acid profile, and functional protein properties.^20, Table 2

Dragonflies are a staple in the diets of many ethnic communities worldwide.²³ They are of two types: Pantala sp. and Sympetrum sp. Dragonflies have a higher protein content than traditional livestock, ranging from 45% to 76%.²⁴ Additionally, 80% of insect lipids contain essential fatty acids.²⁵ Chitin, a component of dragonfly exoskeletons, improves the immune system and provides strong resistance to parasite diseases.^{26, 27} They contain a variety of amino acids, including isoleucine, valine, and leucine. Dragonflies can help with vitamin C deficiency because they contain vitamin C, thiamine, riboflavin, pantothenic acid, niacin, pyridoxine, and vitamin B12.²⁸ In contrast to meat, dragonflies have a higher mineral content than meat. Insect edibles are an excellent solution to malnutrition or for people who do not have the resources to purchase supplements. Insects are not only edible but also medicinal, with antibacterial, immunological, analgesic, and anti-rheumatic properties.²⁹ In dried form, they can be used to treat colitis, cough, malaria, skin allergies, boils, blood pressure, and so on ^28, Table 3.

A study on the nutritional and commercial potential of edible grasshoppers was conducted in Uganda and many East African tribes. They were found to be high in protein, with 36-40%, 4-6mg/kg potassium and phosphorus. The biological value and digestibility have not yet been determined, and further research is underway. The product's overall acceptability was 6.7-7.2 on a 9-point hedonic scale, indicating that it is the flavour, appearance, and aroma that entice people to consume rather than the raw material.^30, Table 4

In addition to their high nutritional value, several other factors must be considered. One significant challenge is cultural and social acceptance. While entomophagy is widespread in Asia, Africa, and Latin America, it is less popular in Western countries, where insects are often associated with disgust, fear, or filth. This negative perception remains a significant barrier to incorporating insect-based foods into mainstream diets. There are also limitations to current research. Most nutritional research focuses on a few commonly consumed insects, such as crickets, grasshoppers, and mealworms, while thousands of edible species go unexplored. Nutrient values also differ greatly depending on species, rearing conditions, and feed, making it difficult to generalize findings Table 5.

Processing methods have a significant impact on the nutritional quality and shelf life of insect products.

For example, freeze-drying preserves proteins and heat-sensitive vitamins, whereas roasting or oven-drying may result in nutrient loss but improve taste and storage stability. Fermentation and grinding into powders improve digestibility and ease of use in foods, but they may shorten shelf life. A direct comparison with traditional animal proteins emphasizes the benefits of insects. Fresh beef and chicken provide 26-27% protein, while fish provides 20%. In contrast, edible insects can have 35-77% protein by dry weight, with crickets and grasshoppers reaching 60-70%. They are also higher in micronutrients, with iron levels reaching 31 mg/100 g and zinc levels reaching 20 mg/100 g, which are often higher than those found in beef or chicken. These traits make insects a promising and sustainable alternative.

Climate has a major impact on agricultural practices and the overall productivity.³² It influences both traditional farming as well as insect farming. It also has a major influence on which crops and livestock are appropriate for a given area in traditional farming. Temperature, precipitation, and seasonal variations can have an impact on crop yields and livestock forage availability. Severe weather conditions, like floods or droughts, put traditional farming systems at serious risk and affect livelihoods and food production. These difficulties are made worse by climate change, which adds unpredictability and may change the geographic distribution of pests and crops. Agriculture has been one of the primary causes of climate change, accounting for about 18% of global greenhouse gas emissions.^{33, 34} Since edible insects appear to be a more sustainable and environmentally friendly source of nutrients than any other farming as they require less land, water, and manpower, they are capable of providing benefits to the economy and environment.³⁵ To feed the world’s growing population, food production has to considerably rise.³⁶ Resources like energy, water, land, and ocean get used up more in the case of traditional farming. Usage of insecticides, and pesticides would dramatically rise. If food production continues in its current manner, deforestation, and environmental degradation is expected. Particularly since livestock production makes up about 70% of all agricultural land used worldwide for food and fodder, it would worsen the environmental issues.³⁶ More feed and cropland will be needed for increased animal production, which could result in more deforestation. It’s not advocating that human should solely rely on insects for sustenance, besides some edible insects can be regarded as regular foods and introduced into society as it has their nutritional benefits and help to prevent hunger and preserve the sustainability of the environment Figure 2.

Figure 2.The bar graph depicts a comparison of traditional farming and edible insect farming35

According to research, crickets require less than 2kg of feed for every kg of body weight increase.³⁷ Conversely, 2.5kg of feed is required for chicken, pork, and up to 10 kg of beef in order to produce a 1kg increase in body weight.³⁸ As a result, crickets ' feed-to-meat ratio is roughly twice as high as that of chickens and four to twelve times higher for pigs and cattle.

When compared to traditional livestock, insects are raised on organic side streams using various biological waste, manure, compost, and human waste, reducing environmental contamination.³⁹ In contrast, traditional livestock uses pesticides, insecticides, and pest repellents, which can pollute the environment and ecosystem. They can also harm soil fertility in the long run.³⁶

Insects emit fewer gases and ammonia than pigs and cattle. Livestock rearing would emit 18% of greenhouse gases. They emit large amounts of methane and nitrous oxide, which contribute significantly to global warming. However, farming of insects such as crickets, locusts, and mealworm larvae produces less than cattle and pigs. Livestock waste, including manure urine, which contains ammonia, contributes to environmental pollution by causing nitrification and soil acidification.³⁶

Insect farming uses less land and water than cattle rearing. By 2025, an estimated 1.8 billion people will live in water-scarce regions. Water scarcity poses a global threat to biodiversity, agriculture, and food production. Agriculture consumes roughly 70% of the world's freshwater.⁴⁰ Meat production requires significant amounts of water. Estimated water requirements for producing 1 kg of meat are 2300 L for chicken, 3500 L for pork, and 22 000-43 000 L for beef.⁴¹ Estimates of the amount of water required to produce 1 kg of edible insects are unknown but are thought to be significantly lower.^36, Table 6

Before consumption, insects must go through certain stages that make them more convenient for people to eat. Some people prefer not to eat insects as they are, so they are grounded into granular or paste forms that can be added to other products as a fortifier. Steaming, boiling, baking, deep-frying, sun-drying, and smoking are the steps involved.⁴² In some tropical countries, insects are eaten as a whole, but allergens pose a challenge. As a result, certain body parts, such as wings and legs, are removed.⁴³ According to research, newly developed products such as patties, pasta, and bread are more appealing to consumers because insects are invisible to their eyes. Insects are further utilized in fish and poultry feed. Maggots, or housefly larvae (Musca domestica), are widely used in Nigeria, Cameroon, Russia, South Korea, and Togo. The use of maggots reduces the need for harmful pesticides in poultry farming. Cricket is the most commonly used pet food. Insects are not popular in dog food, but they are fed to cats.⁴⁴ As a result of allergens, traditional processing methods are no longer considered adequate to meet market demands, therefore, it is necessary to evaluate the technologies. The food chain begins with insect harvesting and ends with the consumer consuming the product on his or her plate. Pre-treatments, drying, and extraction are some of the processing methods. Pretreatment methods can be classified again, such as blanching, which effectively reduces moisture, retains high ash content, asphyxiation, carbon dioxide plus blanching methods, and freezing. Blanching and the carbon dioxide plus blanching method were recommended as the best procedures for preserving insect quality and nutritional composition. The processing technologies used for different insects vary.⁴⁵ After pretreatment, the next step is drying to extend the shelf life. It includes both traditional methods like sun-drying and oven-drying, as well as modern methods like freeze drying and microwave drying. Drying would reduce moisture content, preventing microorganism growth.⁴⁶ Solar and oven drying are commonly used to process whole insect bodies, whereas freeze drying, microwave drying, and some novel drying technologies are primarily used to manufacture insect flour and powders. For commercial industrial production, freeze-drying is the most common method for drying edible insects. It allows for continuous dehydration of frozen insects via sublimation without causing significant physical changes or colour loss. Furthermore, freezing methods appear to have less impact on food flavour, aroma, and nutritional value. Microwave drying is an electromagnetic wave-based technology. Compared to traditional hot air drying, microwave drying produces product quality comparable to freeze-drying, with generally improved aroma and nutritional value. On top of that, microwave drying has a short processing time and produces a product with good microbial stability. One of the disadvantages of microwave drying is uneven heating, which can cause physical damage to the product.^44, Table 7

Consumer acceptance is always a barrier to insect consumption. A wide range of factors influences consumer acceptance of edible insects as food, all of which play an important role in shaping attitudes and behaviours toward insect consumption. Disgust, food neophobia, familiarity, visibility of insects, and taste have a significant impact on consumer willingness to incorporate insects into their diets.^{47, 48}Lack of knowledge about entomophagy is also regarded as a major reason for rejection of insect foods.⁴⁹ Providing consumers with positive tasting experiences and information about the benefits of eating insects can increase familiarity and acceptance.⁵⁰ People are hesitant to incorporate insects as a whole, so insect flours could be used to disguise insects in food products to increase acceptance. Consumer acceptance of insect-based foods is influenced by sociodemographic factors such as gender, age, education level, and household income. A study of Hungarians found that men were more willing to try new things and were less neophobic than women. Most women over the age of 60 did not support entomophagy. The government can change people's attitudes toward insect edibles by promoting novel products in the market.⁵¹ The marketing mix, including product development, pricing, promotion strategies, and retail placement in supermarkets, plays a crucial role in promoting consumer acceptance of insect-based products. Increasing the availability and accessibility of insect-based food products, along with positive marketing efforts, is crucial for fostering consumer willingness to try and purchase them. Most people believe that eating insects is revolting, and this idea has become ingrained in their minds, making it difficult to go. As a result, nutritional composition, increased education, and degustation sections are required to persuade people that insect foods are not harmful but rather beneficial. Exposure to insect-based foods can lead to increased acceptance and decreased reluctance towards them over time. People believe insects are unclean. As shown by studies, disgust is not a valid reason to avoid sustainable foods, as frogs and lobsters, which were once considered junk food, are now considered fine dining in many countries.⁵² Food preferences are formed from childhood, making it difficult to change one's mind and accept any food. Promoting entomophagy is unavoidable, but it takes time to persuade people because it is their choice whether or not to consume insects. Understanding these factors is important for increasing consumer acceptance of edible insects and advancing sustainable food systems.⁵³

The Table 8 provides a comprehensive bibliometric and scientometric analysis of research related to edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition, Figure 3 highlighting the geographical distribution of published articles, total number of co-authorships, and citations. The United States leads in all three categories with 4209 published articles, 38029 co-authorships, and 1026654 citations, indicating its prominent role and impact in this research domain. China and the United Kingdom also show significant contributions with 2500 and 2092 articles, respectively, and high citation counts of 446313 and 545559. Other notable contributors include India, Italy, Germany, Australia, the Netherlands, France, and Canada, each with substantial research outputs and collaborative efforts. The data suggests that European countries such as Germany, Italy, the Netherlands, and France are particularly strong in research collaboration, as evidenced by their high co-authorship numbers. Overall, this analysis underscores the significant global interest and collaborative efforts in the study of sustainable food sources and their acceptance, with the United States, China, and the United Kingdom leading in research impact and output.

Figure 3.Geographical distribution of countries who have contributed in the field related to the subject areas; edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition.

Figure 4 represents authors across world who have contributed in the field of edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition. The Table 9 provides a comprehensive analysis of the most productive and influential authors in the field of edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition. Among the top 10 most productive authors, Laura Gasco and Chrysantus M. Tanga lead with 50 published articles each, highlighting their significant contributions and collaborative efforts, as indicated by their high co-authorship numbers (2743 and 887, respectively). Teja Tscharntke, with 40 documents and an impressive 9365 citations, stands out for the substantial impact of his work. Similarly, Yong Sik Ok, with 39 publications and 18143 citations, is highly influential, underscoring the critical reception of his research. Other notable contributors include Sevgan Subramanian and Sunday Ekesi, who have 39 and 36 documents respectively, reflecting their active engagement in this research domain.

Figure 4.Authors who have contributed in the field of edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition.

In terms of influence in Table 10 measured by citations, David Tilman tops the list with 22855 citations from just 13 documents, signifying groundbreaking work. Yong Sik Ok appears again, reinforcing his dual role as both productive and highly cited. Johan Rockström and Jason Hill, with fewer documents (8 and 5, respectively), have garnered substantial citations (16060 and 14293), highlighting the profound impact of their research. This analysis underscores the significant global efforts and contributions of these leading researchers in advancing the understanding and application of sustainable food systems, with a particular focus on edible insects, sustainability, and nutrition.

The Figure 5 and Table 11 provides a detailed overview of the primary author keywords in the research domain encompassing edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition. The keyword "Edible insects" has the highest occurrences (817) and frequency (1929), indicating a significant focus on the role of insects as a food source. "Sustainability" follows closely with 721 occurrences and a slightly higher frequency of 1952, reflecting the critical importance of sustainable practices in food systems research. "Entomophagy," which involves the practice of eating insects, is also a major area of interest with 604 occurrences and 1592 frequency, highlighting studies on consumer acceptance. Other notable keywords include "Climate change" (422 occurrences, 1044 frequency), "Biodiversity" (381 occurrences, 1018 frequency), and "Food security" (378 occurrences, 1017 frequency), indicating strong links between insect-based food sources and broader environmental and socio-economic issues. Additionally, keywords such as "Agriculture" (357 occurrences, 1043 frequency), "Ecosystem services" (343 occurrences, 810 frequency), "Insects" (328 occurrences, 899 frequency), and "Nutrition" (265 occurrences, 799 frequency) illustrate the multifaceted research exploring the agricultural, ecological, and nutritional dimensions of using edible insects as a sustainable food source.

Figure 5.Core Author Keywords in Edible Insects, Consumer Acceptance, and Environmental Sustainability Research.

Figure 6 and Table 12 highlights the top 10 key contributing documents in the field of edible insects, consumer acceptance, environmental sustainability, sustainable food sources, and nutritional composition, ranked by their citation count. Leading the list is van Huis (2013) with 1186 citations, underscoring its foundational impact on the field. Following this, Verbeke (2015b) and Belluco (2013) have 554 and 503 citations respectively, indicating their significant contributions to consumer acceptance and nutritional studies. Hartmann (2015a) and Tan (2015a) are also highly influential, with citations reflecting their pivotal role in understanding consumer attitudes and sustainable practices. Klunder (2012) and House (2016) further contribute to the discourse on environmental and nutritional benefits. Melgar-Lalanne (2019), despite being a more recent publication, shows a growing influence with 248 citations. Caparros Megido (2014) and Looy (2014) round out the list, each providing critical insights into the practical applications and ecological impacts of edible insects. This ranking emphasizes the diverse and significant research that has shaped the understanding and acceptance of edible insects as sustainable food sources.

Figure 6.Key Contributing Documents in the Field of Edible Insects, Consumer Acceptance, Environmental Sustainability, Sustainable Food Sources, and Nutritional Composition.