Anaphylactic shock and lethal anaphylaxis caused by food consumption in China

Imported allergens in Italy: an emerging issue

Imported allergens are involved in many allergic reactions, with unexpected and unusual implications. They can be involved in developing asthma, allergic rhinoconjunctivitis, Hymenoptera venom allergies and food allergies. Imported allergens can be implied in respiratory allergies attributable to commercial practices and accidental diffusion through air currents that have introduced non-native species in new geographical contexts. Ambrosia artemisiifolia L., a plant native to North America and currently in the western part of Lombardy, represents an example. Moreover, a variation in the pollen concentration in the Northwest Tuscany area and Trentino Alto-Adige was observed. Cannabis sativa is another imported allergen used frequently by adolescents. Regarding potential imported food allergens, there is no validated list. Imported food allergens derive from ethnic foods, referring to Mexican/Latin American, Chinese/Japanese, Southeast Asian, Arab/Middle Eastern and African cuisine. Four insect flours were recently introduced to the European and Italian markets (Acheta domesticus, Alphitobius diaperinus, Tenebrio molitor and Locusta migratoria). The association between the accidental introduction through commercial traffic, climate change, and the absence of natural enemies in the destination ecosystem is related to the introduction of a specific Hymenoptera, Vespa velutina, in Italy and Europe. External events attributable to human activities, such as climate change and the introduction of non-native plants, foods and Hymenoptera through trade, have contributed to the issue of imported allergens. Making the correct diagnosis and guiding the diagnostic and therapeutic path in this particular context represent the concerns of the pediatric allergist.

The Potential of Edible Insects as a Safe, Palatable, and Sustainable Food Source in the European Union

Entomophagy describes the practice of eating insects. Insects are considered extremely nutritious in many countries worldwide. However, there is a lethargic uptake of this practice in Europe where consuming insects and insect-based foodstuffs is often regarded with disgust. Such perceptions and concerns are often due to a lack of exposure to and availability of food-grade insects as a food source and are often driven by neophobia and cultural norms. In recent years, due to accelerating climate change, an urgency to develop alternate safe and sustainable food-sources has emerged. There are currently over 2000 species of insects approved by the World Health Organization as safe to eat and suitable for human consumption. This review article provides an updated overview of the potential of edible insects as a safe, palatable, and sustainable food source. Furthermore, legislation, food safety issues, and the nutritional composition of invertebrates including, but not limited, to crickets (Orthoptera) and mealworms (Coleoptera) are also explored within this review. This article also discusses insect farming methods and the potential upscaling of the industry with regard to future prospects for insects as a sustainable food source. Finally, the topics addressed in this article are areas of potential concern to current and future consumers of edible insects.

Novel insect-based child nutrition: the position of the nutritional committee of the Italian society of pediatric gastroenterology, hepatology and nutrition (SIGENP)

BACKGROUND

The European Union (EU) approved the placement on European market of insect-based novel foods. Those foods were defined safe for the consumption for all European population, including children.

MAIN BODY

The nutrition committee of the Italian society of Paediatric Hepatology and Nutrition (SIGENP) performed literature research to understand benefits and risk of those use of those NF for Italian children. A special attention was reserved to the European Food Safety Agency (EFSA) reports upon which those novel insect-based were approved.

CONCLUSIONS

Based on the current knowledge, despite a possible ecological advantage, the group of expert suggests additional researches before pronouncing on a possible use for children diet, because of insufficient evidence on nutritional benefits and possible food allergies.

A review on edible insects in China: Nutritional supply, environmental benefits, and potential applications

This review explored the potential of edible insects to address the challenges of malnutrition and food security. Although grain production in China has met the Food and Agriculture Organization standards, the shortage of protein supply is still a big issue. Moreover, expanding livestock farming is considered unsustainable and environmentally unfriendly. Edible insects have become an alternative with higher sustainable and ecological properties. There are 324 species of insects currently consumed in China, and they have high nutritional value, with a rich source of protein and unsaturated fatty acids. Insect farming provides numerous benefits, including green feeds for livestock, poultry, and aquaculture, sustainable organic waste management, as well as industrial and pharmaceutical raw materials. The food toxicological evaluations conducted in China indicated that edible insects are safe for general consumption by the Chinese, but allergies and other related food safety issues should not be ignored. Consumer acceptance is another barrier to overcome, with different schemas between China and Western countries. More research on the potential functions of edible insects and their product development may enhance their acceptance in China. Overall, incorporating edible insects into our diet is a promising solution to address challenges related to protein supply and food security. To ensure safety and sustainability, appropriate legislation, quality regulations, large-scale insect farms, and acceptable processing techniques are necessary. Moreover, more scientific research and social awareness are required to promote the culture and utilization of edible insects in China.

Effects of Insect Consumption on Human Health: A Systematic Review of Human Studies

Insects have been consumed as food in diverse cultures worldwide, gaining recognition as a sustainable and nutritious food source. This systematic review aims to update information on the impact of insect consumption on human health based on human randomized controlled trials (RCTs) and allergenicity assessment studies. Following PRISMA guidelines, studies published in the last 10 years were analyzed. From one-thousand and sixty-three retrieved references, nine RCTs and five allergenicity studies were analyzed. Post-prandial amino acid levels increased after insect protein consumption. In comparison with other protein sources, insect protein showed no significant differences in the area under the curve (AUC) values for essential amino acids but tended to have lower peaks and peak later. In terms of muscle protein synthesis, there were no significant differences between insect protein and other protein sources. Glucose levels did not differ; however, insulin levels were lower after the consumption of insect-based products. The effects on inflammatory markers and microbiota composition were inconclusive and the studies did not show significant effects on appetite regulation. Allergenicity assessments revealed a sensitisation and cross-reactivity between insect allergens and known allergens. A partial reduction of cross-allergenicity was observed via thermal processing. Insect protein is an adequate protein source with promising health benefits; however, further research is needed to fully understand its potential and optimise its inclusion into the human diet.

EAACI Molecular Allergology User's Guide 2.0

Since the discovery of immunoglobulin E (IgE) as a mediator of allergic diseases in 1967, our knowledge about the immunological mechanisms of IgE-mediated allergies has remarkably increased. In addition to understanding the immune response and clinical symptoms, allergy diagnosis and management depend strongly on the precise identification of the elicitors of the IgE-mediated allergic reaction. In the past four decades, innovations in bioscience and technology have facilitated the identification and production of well-defined, highly pure molecules for component-resolved diagnosis (CRD), allowing a personalized diagnosis and management of the allergic disease for individual patients. The first edition of the "EAACI Molecular Allergology User's Guide" (MAUG) in 2016 rapidly became a key reference for clinicians, scientists, and interested readers with a background in allergology, immunology, biology, and medicine. Nevertheless, the field of molecular allergology is moving fast, and after 6 years, a new EAACI Taskforce was established to provide an updated document. The Molecular Allergology User's Guide 2.0 summarizes state-of-the-art information on allergen molecules, their clinical relevance, and their application in diagnostic algorithms for clinical practice. It is designed for both, clinicians and scientists, guiding health care professionals through the overwhelming list of different allergen molecules available for testing. Further, it provides diagnostic algorithms on the clinical relevance of allergenic molecules and gives an overview of their biology, the basic mechanisms of test formats, and the application of tests to measure allergen exposure.

Safety of frozen and freeze‐dried formulations of the lesser mealworm (Alphitobius diaperinus larva) as a Novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on frozen and dried formulations from whole lesser mealworm (Alphitobius diaperinus larva) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The term lesser mealworm refers to the larval form of the insect species Alphitobius diaperinus. The NF comprises the frozen and freeze‐dried formulations of the lesser mealworm as whole or in the form of a paste or powder. Apart from water in the frozen formulations (whole, paste), the main components of the NF are crude protein and fat, besides smaller amounts of digestible carbohydrates and fibre (chitin). The Panel notes that the levels of contaminants in the NF depend on the concentration of such substances in the insect feed. The Panel notes furthermore that the true protein levels in the NF are overestimated when using the nitrogen‐to‐protein conversion factor of 6.25, due to the presence of non‐protein nitrogen from chitin. The applicant proposed to use the NF formulations added as an ingredient to various food products such as cereal bars, pasta, meat imitates and bakery products. The target population is the general population. Additionally, the applicant proposed to use the NF as a food supplement in adults. The Panel notes that, considering that the NF will not be the sole source of dietary protein, and the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The submitted subchronic 90‐day toxicity study with the NF as testing material did not raise safety concerns. The Panel considers that the consumption of the NF may induce primary sensitisation and allergic reactions to lesser mealworm proteins and may cause allergic reactions in subjects with allergy to crustaceans and dust mites. Additionally, allergens from the feed may end up in the NF. Allergenicity aside, the Panel concludes that the NF is safe under the proposed uses and use levels.

Road to The Red Carpet of Edible Crickets through Integration into the Human Food Chain with Biofunctions and Sustainability: A Review

The Food and Agriculture Organization of the United Nations (FAO) estimates that more than 500 million people, especially in Asia and Africa, are suffering from malnutrition. Recently, livestock farming has increased to supply high-quality protein, with consequent impact on the global environment. Alternative food sources with high nutritive values that can substitute livestock demands are urgently required. Recently, edible crickets have been promoted by the FAO to ameliorate the food crisis. In this review, the distribution, nutritive values, health-promoting properties (antioxidant, anti-inflammatory, anti-diabetic and anti-obesity), safety, allergenicity as well as the potential hazards and risks for human consumption are summarized. Cricket farming may help to realize the United Nations sustainable development goal No. 2 Zero Hunger. The sustainability of cricket farming is also discussed in comparison with other livestock. The findings imply that edible crickets are safe for daily intake as a healthy alternative diet due to their high protein content and health-promoting properties. Appropriate use of edible crickets in the food and nutraceutical industries represents a global business potential. However, people who are allergic to shellfish should pay attention on cricket allergy. Thus, the objective of this review was to present in-depth and up-to-date information on edible crickets to advocate and enhance public perception of cricket-based food.

The use of alternative food sources to improve health and guarantee access and food intake

To feed and provide Food Security to all people in the world is a big challenge to be achieved with the 2030 Agenda. Undernutrition and obesity are to the opposite of a healthy nutritional status. Both conditions are associated with unbalanced nutrition, absence of food or excess of non-nutritive foods intake. These two nutritional conditions associated with food production are closely related to some goals highlighted by the United Nations in the 2030 Agenda to achieve sustainable world development. In this context, the search for alternative foods whose sustainable production and high nutritional quality guarantee regular access to food for the population must be encouraged. Alternative foods can contribute to Food Security in many ways as they contribute to the local economy and income generation. Popularizing and demystifying the uses of unconventional food plants, ancestral grains, flowers, meliponiculture products, and edible insects as sources of nutrients and non-nutrients is another challenge. Herein, we present an overview of alternative foods - some of them cultivated mostly in Brazil - that can be explored as sources of nutrients to fight hunger and malnutrition, improve food production and the economic growth of nations.

Safety of frozen and dried formulations from whole house crickets (Acheta domesticus) as a Novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Food and Food Allergens (NDA) was asked to deliver an opinion on the safety of frozen and dried formulations from house crickets (Acheta domesticus) as a novel food pursuant to Regulation (EU) 2015/2283. The NF is proposed in three formulations: (i) frozen, (ii) dried, (iii) ground. The main components of the NF are protein, fat and fibre (chitin) in the dried form of the NF, and water, protein, fat and fibre (chitin) in the frozen form of the NF. The Panel notes that the concentrations of contaminants in the NF depend on the occurrence levels of these substances in the insect feed. The Panel further notes that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf-life. The NF has a high-protein content, although the true protein levels in the NF are overestimated when using the nitrogen-to-protein conversion factor of 6.25, due to the presence of non-protein nitrogen from chitin. The applicant proposed to use the NF in the form of a snack, and as a food ingredient in a number of food products. The target population proposed by the applicant is the general population. The Panel notes that, considering the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The Panel notes that no genotoxicity and no subchronic toxicity studies with the NF were provided by the applicant. Considering that no safety concerns arise from the history of use of A. domesticus or from the compositional data of the NF, the Panel identified no other safety concerns than allergenicity. The Panel considers that the consumption of the NF might trigger primary sensitisation to A. domesticus proteins and may cause allergic reactions in subjects allergic to crustaceans, mites and molluscs. Additionally, allergens from the feed may end up in the NF. The Panel concludes that the NF is safe under the proposed uses and use levels.

Seafood Allergy in Asia: Geographical Specificity and Beyond

Asian countries have unique ways of food processing and dietary habits that may explain the observed differences in the prevalence, natural history, epidemiology and sensitization pattern of food allergic diseases when compared to western countries. Per capita consumption of seafood, including fish and shellfish, is well above the global average for many Asian countries because of their coastal geographical location and rich seafood supply. The wide availability and high abundance of seafood in Asian countries have shaped a diverse way of processing and eating this major food group. Such unique features have significant impact on the sensitization profile and allergenicity of Asians to fish and shellfish. For example, fish and shellfish are eaten raw in some countries that may promote sensitization to heat-labile allergens not otherwise seen in other regions. Fermented fish sauce is commonly used as a condiment in some countries which may promote fish sensitization. Shrimp head and shrimp roe are regarded as delicacies in some countries, but their allergen profiles are yet to be characterized. Freshwater fish and shellfish are a common food source in many Asian countries but the allergenicity of many such species remains unknown. In this review, we discuss factors that may contribute to differences in molecular profile and sensitization pattern for fish and shellfish that are observed in Asian populations and revisit the current status of seafood allergy in this part of the world. Acknowledging the similarities and differences of seafood allergy patterns between Asian and western populations can help us refine a better strategy for diagnosing and managing seafood allergy.

Safety of frozen and dried formulations from migratory locust (Locusta migratoria) as a Novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Food and Food Allergens (NDA) was asked to deliver an opinion on the safety of frozen and dried formulations from migratory locust (Locusta migratoria) as a novel food pursuant to Regulation (EU) 2015/2283. The term migratory locust refers to the adult of the insect species Locusta migratoria. The NF is proposed in three formulations i) frozen without legs and wings; ii) dried without legs and wings; iii) ground with legs and wings. The main components of the NF are protein, fat and fibre (chitin) in the dried form of the NF, and water, protein, fat and fibre (chitin) in the frozen form of the NF. The Panel notes that the concentration of contaminants in the NF depends on the occurrence levels of these substances in the insect feed. The Panel notes that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf-life. The NF has a high protein content, although the true protein levels in the NF are overestimated when using the nitrogen-to-protein conversion factor of 6.25, due to the presence of non-protein nitrogen from chitin. The applicant proposed to use the NF as frozen, dried and ground in the form of snack, and as a food ingredient in a number of food products. The target population proposed by the applicant is the general population. The Panel notes that considering the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The submitted history of use and toxicity studies from literature did not raise safety concerns. The Panel considers that the consumption of the NF might trigger primary sensitisation to L. migratoria proteins and may cause allergic reactions in subjects with allergy to crustaceans, mites and molluscs. Additionally, allergens from the feed may end up in the NF. The Panel concludes that the NF is safe under the proposed uses and use levels.

Allergens from Edible Insects: Cross-reactivity and Effects of Processing

PURPOSE OF REVIEW

The recent introduction of edible insects in Western countries has raised concerns about their safety in terms of allergenic reactions. The characterization of insect allergens, the sensitization and cross-reactivity mechanisms, and the effects of food processing represent crucial information for risk assessment.

RECENT FINDINGS

Allergic reactions to different insects and cross-reactivity with crustacean and inhalant allergens have been described, with the identification of new IgE-binding proteins besides well-known pan-allergens. Depending on the route of sensitization, different potential allergens seem to be involved. Food processing may affect the solubility and the immunoreactivity of insect allergens, with results depending on species and type of proteins. Chemical/enzymatic hydrolysis, in some cases, abolishes immunoreactivity. More studies based on subjects with a confirmed insect allergy are necessary to identify major and minor allergens and the role of the route of sensitization. The effects of processing need to be further investigated to assess the risk associated with the ingestion of insect-containing food products.

Safety of dried yellow mealworm (Tenebrio molitor larva) as a novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on dried yellow mealworm (Tenebrio molitor larva) as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The term yellow mealworm refers to the larval form of the insect species Tenebrio molitor. The NF is the thermally dried yellow mealworm, either as whole dried insect or in the form of powder. The main components of the NF are protein, fat and fibre (chitin). The Panel notes that the levels of contaminants in the NF depend on the occurrence levels of these substances in the insect feed. The Panel notes that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf life. The NF has a high protein content, although the true protein levels in the NF are overestimated when using the nitrogen-to-protein conversion factor of 6.25, due to the presence of non-protein nitrogen from chitin. The applicant proposed to use the NF as whole, dried insect in the form of snacks, and as a food ingredient in a number of food products. The target population proposed by the applicant is the general population. The Panel notes that considering the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The submitted toxicity studies from the literature did not raise safety concerns. The Panel considers that the consumption of the NF may induce primary sensitisation and allergic reactions to yellow mealworm proteins and may cause allergic reactions in subjects with allergy to crustaceans and dust mites. Additionally, allergens from the feed may end up in the NF. The Panel concludes that the NF is safe under the proposed uses and use levels.

Insect Allergens on the Dining Table

Edible insects are important sources of nutrition, particularly in Africa, Asia, and Latin America. Recently, edible insects have gained considerable interest as a possible solution to global exhaustion of the food supply with population growth. However, little attention has been given to the adverse reactions caused by insect consumption. Here, we provide an overview of the food allergens in edible insects and offer insights for further studies. Most of the edible insect allergens identified to date are highly cross-reactive invertebrate pan-allergens such as tropomyosin and arginine kinase. Allergic reactions to these allergens may be cross-reactions resulting from sensitization to shellfish and/or house dust mites. No unique insect allergen specifically eliciting a food allergy has been described. Many of the edible insect allergens described thus far have counterpart allergens in cockroaches, which are an important cause of respiratory allergies, but it is questionable whether inhalant allergens can cause food allergies. Greater effort is needed to characterize the allergens that are unique to edible insects so that safe edible insects can be developed. The changes in insect proteins upon food processing or cooking should also be examined to enhance our understanding of edible insect food allergies.

Quantitative allergenicity risk assessment of food products containing yellow mealworm (Tenebrio molitor)

Insect-based foods are starting to enter the EU market, raising concerns about their safety. Allergic consumers might be exposed to even a greater risk, since insects have proven to trigger allergic symptoms, particularly in patients sensitised to crustaceans. Current legislation does not enforce producers to include insects in the list of allergenic ingredients. Food allergenicity risk assessment (FARA) is still at its infancy, and the debate on the need to define allergen thresholds is open. In this paper, we aimed at applying the concepts of stochastic quantitative FARA to describe present and future scenarios of exposure to foods containing Tenebrio molitor, the yellow mealworm. According to our risk characterisation, mealworm-based food products represent a major risk for individuals allergic to crustaceans to develop symptoms after the consumption of a dose lower than a serving size. Moreover, other allergic consumers might be at risk. A correct labelling of insect containing foods would help safeguarding the health of EU allergic consumers. Quantitatively assessing the risk of allergenicity provides a clear description of the problem, facilitating the decisional process of the risk manager, supporting the implementation of effective allergen management procedures and limiting the phenomenon of uninformative precautionary labelling.

Shotgun proteomics, in-silico evaluation and immunoblotting assays for allergenicity assessment of lesser mealworm, black soldier fly and their protein hydrolysates

Since 2018, insects have belonged the category of Novel Foods and the presence of allergens represents one of the main hazards connected to their consumption, also due to the potential cross-reactivity with Arthropoda pan-allergens. In the present work, the allergenicity assessment of black soldier fly and lesser mealworm was performed with a shotgun bottom-up proteomic approach combined with in-silico assessment, followed by IgG- and IgE-immunoblotting experiments. The peptides identified, filtered for their abundance and robustness, belonged mainly to muscle proteins, which represented the most abundant protein group. The relevant potential allergens were in-silico identified by sequence similarity to known allergens, and among them tropomyosin resulted the most abundant insect allergen. IgG-immunoblotting analysis with anti-Tropomyosin I antibodies and IgE-immunoblotting assay with serum from patient allergic to crustacean tropomyosin were performed in order to assess the immunoreactivity in both insects. The immunoassays were carried out also on protein hydrolysates extracted by treating insects with Protease from Bacillus licheniformis (1%, 60 °C, pH 7.5). While IgG-immunoblotting demonstrated the loss of immunoreactivity for both hydrolysates, IgE-immunoblotting showed a partial immunoreactivity preservation, also after hydrolysis, in the case of black soldier fly hydrolysate, and a total loss of immunoreactivity for lesser mealworm hydrolysate.

Insights into the Allergenic Potential of the Edible Yellow Mealworm (Tenebrio molitor)

The edible yellow mealworm (Tenebrio molitor), contains an extremely diverse panel of soluble proteins, including proteins with structural functions such as muscle proteins, as well as proteins involved in metabolic functions such as enzymes. Most of these proteins display a more or less pronounced allergenic character toward previously sensitized people, especially people allergic to shrimps and other shellfish. A mass spectrometry approach following the separation of a mealworm protein, extracted by sodiumdodecyl sulfate-polyacrylamide gel electrophoresis, allowed us to identify up to 106 distinct protein fractions including molecules with structural and functional functions, susceptible to developing an allergenic potential due to the possibility of immunoglobulin E-binding cross-reactions with their counterparts occurring in shellfish. In this respect, most of the sera from people allergic to shrimps reacted with the mealworm protein extract in Western blot experiments. Moreover, the potential mealworm allergens triggered the in vitro degranulation of rat leukemic basophils transfected with the human high-affinity IgE receptor (FcεRI), upon sensitization by the IgE-containing sera from people allergic to shrimps and other shellfish foods. Owing to the large repertoire of IgE-binding cross-reacting allergens the yellow mealworm shares with other phylogenetically-related groups of arthropods, it would seem prudent to inform the consumers, especially those allergic to shellfish, by appropriate labeling on edible mealworm packages about the potential risk of developing an allergic reaction.

Entomophagy: Nutritional, ecological, safety and legislation aspects

Globally, there is a need to seek alternative sources of protein in addition to meat. This has led to considerable interest in edible insects. Such insects form part of cultures and diets in many Asian and African countries, and are an excellent source of essential nutrients, minerals, vitamins and proteins. Furthermore, they have been reported to be sustainable. The ecological importance of insects is related to their short life cycles when reared and farmed. This makes them ideal in mitigating greenhouse gas emissions, cutting land uses and polluted water, and reducing environmental contamination. However, the use of edible insects as food in Europe is minimal. To ensure safety of insects when eaten as food, considerations should be made on: microbiological contamination; toxicological hazards, e.g. chemical hazards and antinutrients; allergenicity issues that are related to different exposures, including injection, ingestion, inhalation and skin contact. In this review, we summarize the nutritional and sustainable values of edible insects, look at safety and legislative measures and we finally discuss future issues.

EAACI position paper: Comparing insect hypersensitivity induced by bite, sting, inhalation or ingestion in human beings and animals

Adverse reactions to insects occur in both human and veterinary patients. Systematic comparison may lead to improved recommendations for prevention and treatment in all species. In this position paper, we summarize the current knowledge on insect allergy induced via stings, bites, inhalation or ingestion, and compare reactions in companion animals to those in people. With few exceptions, the situation in human insect allergy is better documented than in animals. We focus on a review of recent literature and give overviews of the epidemiology and clinical signs. We discuss allergen sources and allergenic molecules to the extent described, and aspects of diagnosis, prophylaxis, management and therapy.

Edible insects: Cross-recognition of IgE from crustacean- and house dust mite allergic patients, and reduction of allergenicity by food processing

BACKGROUND

Insects have become increasingly interesting as alternative nutrient sources for feeding humans and animals, most reasonably in processed form. Initially, some safety aspects - among them allergenicity - need to be addressed.

OBJECTIVE

To reveal the cross-reactivity of shrimp-, mite- and flies-allergic patients to different edible insects, and further to assess the efficacy of food processing in reducing the recognition of insect proteins by patients' IgE and in skin prick testing of shrimp-allergic patients.

METHODS

IgE from patients allergic to crustaceans, house dust mite or flies was evaluated for cross-recognition of proteins in house cricket Acheta domesticus (AD), desert locust Schistocerca gregaria (SG) and Yellow mealworm Tenebrio molitor (TM). Changes in IgE-binding and SPT-reactivity to processed insect extracts were determined for migratory locust (Locusta migratoria, LM), after different extraction methods, enzymatic hydrolysis, and thermal processing were applied.

RESULTS

IgE from patients with crustacean-allergy shows cross-recognition of AD, SG and stable flies; house dust mite allergics' IgE binds to AD and SG; and the flies-allergic patient recognized cricket, desert locust and migratory locust. Cross-reactivity and allergenicity in SPT to LM can be deleted by conventional processing steps, such as hydrolysis with different enzymes or heat treatment, during the preparation of protein concentrates.

CONCLUSION

The results show that crustacean-, HDM- and stable flies-allergic patients cross-recognize desert locust and house cricket proteins, and crustacean-allergic patients also flies proteins. Furthermore, this study shows that appropriate food processing methods can reduce the risk of cross-reactivity and allergenicity of edible insects.

Edible insects - defining knowledge gaps in biological and ethical considerations of entomophagy

While seeking novel food sources to feed the increasing population of the globe, several alternatives have been discussed, including algae, fungi or in vitro meat. The increasingly propagated usage of farmed insects for human nutrition raises issues regarding food safety, consumer information and animal protection. In line with law, insects like any other animals must not be reared or manipulated in a way that inflicts unnecessary pain, distress or harm on them. Currently, there is a great need for research in the area of insect welfare, especially regarding species-specific needs, health, farming systems and humane methods of killing. Recent results from neurophysiological, neuroanatomical and behavioral sciences prompt caution when denying consciousness and therefore the likelihood of presence of pain and suffering or something closely related to it to insects. From an animal protection point of view, these issues should be satisfyingly solved before propagating and establishing intensive husbandry systems for insects as a new type of mini-livestock factory farming.

Insect (food) allergy and allergens

Insects represent an alternative for meat and fish in satisfying the increasing demand for sustainable sources of nutrition. Approximately two billion people globally consume insects. They are particularly popular in Asia, Latin America, and Africa. Most research on insect allergy has focussed on occupational or inhalation allergy. Research on insect food safety, including allergenicity, is therefore of great importance. The objective of this review is to provide an overview of cases reporting allergy following insect ingestion, studies on food allergy to insects, proteins involved in insect allergy including cross-reactive proteins, and the possibility to alter the allergenic potential of insects by food processing and digestion. Food allergy to insects has been described for silkworm, mealworm, caterpillars, Bruchus lentis, sago worm, locust, grasshopper, cicada, bee, Clanis bilineata, and the food additive carmine, which is derived from female Dactylopius coccus insects. For cockroaches, which are also edible insects, only studies on inhalation allergy have been described. Various insect allergens have been identified including tropomyosin and arginine kinase, which are both pan-allergens known for their cross-reactivity with homologous proteins in crustaceans and house dust mite. Cross-reactivity and/or co-sensitization of insect tropomyosin and arginine kinase has been demonstrated in house dust mite and seafood (e.g. prawn, shrimp) allergic patients. In addition, many other (allergenic) species (various non-edible insects, arachnids, mites, seafoods, mammals, nematoda, trematoda, plants, and fungi) have been identified with sequence alignment analysis to show potential cross-reactivity with allergens of edible insects. It was also shown that thermal processing and digestion did not eliminate insect protein allergenicity. Although purified natural allergens are scarce and yields are low, recombinant allergens from cockroach, silkworm, and Indian mealmoth are readily available, giving opportunities for future research on diagnostic allergy tests and vaccine candidates.

Edible insects in China: Utilization and prospects

The use of edible insects has a long history in China, where they have been consumed for more than 2000 years. In general, the level of acceptance is high for the consumption of insects in China. Many studies on edible insects have been conducted in the last 20 years, and the scope of the research includes the culture of entomophagy and the identification, nutritional value, farming and breeding of edible insects, in addition to food production and safety. Currently, 324 species of insects from 11 orders are documented that are either edible or associated with entomophagy in China, which include the common edible species, some less commonly consumed species and some medicinal insects. However, only approximately 10 to 20 types of insects are regularly consumed. The nutritional values for 174 species are available in China, including edible, feed and medicinal species. Although the nutritional values vary among species, all the insects examined contain protein, fat, vitamins and minerals at levels that meet human nutritional requirements. Edible insects were, and continue to be, consumed by different ethnic groups in many parts of China. People directly consume insects or food products made from insects. The processing of products from insect protein powder, oil and chitin, and the development of healthcare foods has been studied in China. People also consume insects indirectly by eating livestock that were fed insects, which may be a more acceptable pathway to use insects in human diets. Although limited, the data on the food safety of insects indicate that insects are safe for food or feed. Incidences of allergic reactions after consuming silkworm pupae, cicadas and crickets have been reported in China. Insect farming is a unique breeding industry in rural China and is a source of income for local people. Insects are reared and bred for human food, medicine and animal feed using two approaches in China: the insects are either fully domesticated and reared completely in captivity or are partially raised in captivity, and the insect habitat is manipulated to increase production. Depending on the type of relationship the insect has with humans, plants and the environment, different farming strategies are used. The social and scientific communities must work together to promote the use of insects as food and feed.

Postharvest processes of edible insects in Africa: A review of processing methods, and the implications for nutrition, safety and new products development

In many African cultures, insects are part of the diet of humans and domesticated animals. Compared to conventional food and feed sources, insects have been associated with a low ecological foot print because fewer natural resources are required for their production. To this end, the Food and Agriculture Organization of the United Nations recognized the role that edible insects can play in improving global food and nutrition security; processing technologies, as well as packaging and storage techniques that improve shelf-life were identified as being crucial. However, knowledge of these aspects in light of nutritional value, safety, and functionality is fragmentary and needs to be consolidated. This review attempts to contribute to this effort by evaluating the available evidence on postharvest processes for edible insects in Africa, with the aim of identifying areas that need research impetus. It further draws attention to potential postharvest technology options for overcoming hurdles associated with utilization of insects for food and feed. A greater research thrust is needed in processing and this can build on traditional knowledge. The focus should be to establish optimal techniques that improve presentation, quality and safety of products, and open possibilities to diversify use of edible insects for other benefits.

Allergic risks of consuming edible insects: A systematic review

The expected future demand for food and animal-derived protein will require environment-friendly novel food sources with high nutritional value. Insects may be one of such novel food sources. However, there needs to be an assessment of the risks associated with their consumption, including allergic risks. Therefore, we performed a systematic review aiming to analyse current data available regarding the allergic risks of consuming insects. We reviewed all reported cases of food allergy to insects, and studied the possibility of cross-reactivity and co-sensitisation between edible insects, crustaceans and house dust mites. We analysed a total of 25 articles - eight assessing the cross-reactivity/co-sensitisation between edible insects, crustaceans and house dust mites; three characterizing allergens in edible insects and 14 case reports, describing case series or prevalence studies of food allergy caused by insects. Cross-reactivity/co-sensitisation between edible insects and crustaceans seems to be clinically relevant, while it is still unknown if co-sensitisation between house dust mites and edible insects can lead to a food allergy. Additionally, more information is also needed about the molecular mechanisms underlying food allergy to insects, although current data suggest that an important role is played by arthropod pan-allergens such as tropomyosin or arginine kinase.

Is mealworm or shrimp allergy indicative for food allergy to insects?

SCOPE

The growing world population is a key driver for the exploration of sustainable protein sources to ensure food security. Mealworm and other insects are promising candidates. Previously we found that shrimp allergic patients are at risk for mealworm allergy, and that mealworm can induce a primary allergy . This study set out to investigate the allergenic potential of edible insects, suggested for human consumption by agencies such as WHO/FAO, in both the shrimp (potentially cross-reactive) and primary mealworm allergic population. The following insects were studied: mealworm, house cricket, giant mealworm, lesser mealworm, African grasshopper, large wax moth, and black soldier fly.

METHODS AND RESULTS

Fifteen shrimp (mealworm sensitized or allergic) patients and four primary mealworm allergic subjects, who participated in previous studies, were included. All shrimp allergic patients were sensitized to multiple insects with similar response profiles for all insects tested. Primary mealworm allergic patients, showed IgE binding to proteins from only a few insects on immunoblot, although basophil activation test was positive for all tested insects.

CONCLUSION

Shrimp allergic patients are most likely at risk of food allergy to mealworm and other insects. Primary mealworm allergy does not mean subjects are likely to react to all insects.

IgE Sensitization Patterns to Commonly Consumed Foods Determined by Skin Prick Test in Korean Adults

Offending food allergens can vary with regional preferences in food consumption. In this study, we analysed sensitization rates to commonly consumed foods in Korean adults suspected of having food allergy. One hundred and thirty four subjects underwent a skin prick test (SPT) with 55 food allergens, of which 13 were made by our laboratory and the rest were commercially purchased. Of the 134 patients, 73 (54.5%) were sensitized to one or more food allergens. Sensitization to chrysalis was detected most frequently, at a rate of 25.4%. Sensitization rates to other food allergens were as follows: maize grain (13.4%), shrimp (11.9%), almond (11.1%), wheat flour (8.2%), lobster (8.2%), buckwheat (8.2%), mackerel (5.2%), pollack (5.2%), halibut (4.5%), peanut (4.5%), anchovy (4.4%), squid (3.7%), saury (3.0%), common eel (3.0%), yellow corvina (3.0%), hairtail (2.2%), octopus (2.2%), and others. In addition to well-known food allergens, sensitivity to mackerel, chrysalis, pollack, and halibut, which are popular foods in Korea, was observed at high rates in Korean adults. We suggest that the SPT panel for food allergy in Korea should include these allergens.