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Edible Insects as a Source of Food Allergens

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Increasing global population increasingly limited by resources has spurred interest in novel food sources. Insects may be an alternative food source in the near future, but consideration of insects as a food requires scrutiny due to risk of allergens. Currently, the insect Dactylopius coccus, known as cochineal, is used to produce carmine, a natural red pigment used in food, which has caused allergic reactions. This study investigated allergens of cochineal focusing on purification from the pigment. Mass spectrometry identified a previously described major allergen of cochineal and a tropomyosin, although further work is required. Tropomyosin is a major cross-reactive allergen across invertebrates including insects and shellfish and has multiple isoforms per species of varying function, sequence, and expression. Extractions of diverse insects must be sufficiently representative to be comparable. This study used a mass spectrometry compatible buffer and a zwitterionic-chaotropic buffer with sequential extractions. Both buffers were found to be sufficiently representative via rabbit anti-shrimp tropomyosin IgG. These extractions were used for further immunoblotting with shrimp-allergic sera and sera from subjects with self-reported shellfish allergy or sensitization to shellfish. Tropomyosins were cloned from several samples and their sequences investigated for epitopes and semi-quantitative massspectrometry. A pattern of low reactivity was found for several samples not corroborated by quantitative data. Further cloning is necessary to align these data sets. Resistance to digestion is a common test for potential allergenicity as epitopes may persist after digestion. Use of pepsin is standard, although this may not be as representative as a direct assay of the source food. Simulated gastric pepsinolysis was performed with defatted Acheta domesticus cricket powder and immunoblotted against shrimp-allergic sera and rabbit anti-tropomyosin IgG. Patterns of reactivity were similar against non-reduced samples with relatively lower reactivity with allergic sera against reduced samples. The allergic sera was predominantly cross-reactive with tropomyosin with lesser reactivity against reduced forms of cricket tropomyosins. It was found that insect based foods pose potential risk to shellfish allergic patients due to homologous proteins including tropomyosin. Advisors: Philip E. Johnson and Michael G. Zeece
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... In some places, they are considered a delicacy, while in others, they are the main diet. Insects represent high quality food for humans and animals, and according to various data, 1600-2100 insect species are consumed worldwide [7,11,19]. ...
... In the first century AD, Roman historian Pliny the Elder described cossus, which is the larva of the longhorn beetle. Li Shizhen wrote a comprehensive book about Chinese medicine and food during the Ming Dynasty in China, which included many insects [17,19]. ...
... In 1737 in France, René Antoine Ferchault de Réaumur indicated the inconsistency of the fact that frogs, snakes, and lizards were eaten across France, but entomophagy caused disgust [19]. ...
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Introduction According to forecasts, the world population will exceed nine billion people by 2050 [1, 2, 3]. It is expected that the demand for meat products will increase by more than 75% in 2050 compared to the present level. The growth in per capita meat consumption will be greater in developing countries (from 28 kg in 2005/2007 to 42 kg in 2050) than in developed countries (from 80 to 91 kg). At present, developing countries mainly account for this increase in demand (113%), while it is less in developed ones (27%). It is estimated that the growth in meat consumption will be more than 150% in several world regions from 2010 to 2050. For example, it will be 187% in Middle East and North Africa, 202% in Sub-Saharan Africa and 272% in South Asia [4, 5]. Developed countries have higher per capita protein consumption than developing countries (about 96 g/ capita/day); however, a significant proportion (65%) of this amount is meat. On the contrary, protein consumption in developing countries is significantly lower (about 56 g/capita/day) and animal protein accounts only for 15%. With that, animal husbandry, including production of forage crops, occupies about 70% of world agricultural lands (or 30% of Earth's land surface) and uses 77 million tons of plant or animal protein to produce only 58 million tons of protein for human consumption annually [6]. The growth in the global demand for meat and scarcity of land resources stimulate searching for alternative protein sources [4, 7].
... In some places, they are considered a delicacy, while in others, they are the main diet. Insects represent high quality food for humans and animals, and according to various data, 1600-2100 insect species are consumed worldwide [7,11,19]. ...
... In the first century AD, Roman historian Pliny the Elder described cossus, which is the larva of the longhorn beetle. Li Shizhen wrote a comprehensive book about Chinese medicine and food during the Ming Dynasty in China, which included many insects [17,19]. ...
... In 1737 in France, René Antoine Ferchault de Réaumur indicated the inconsistency of the fact that frogs, snakes, and lizards were eaten across France, but entomophagy caused disgust [19]. ...
Article
The current state and research priorities in the field of using insects as foods and their components are examined. At present, entomophagy is practiced in Africa, South America and Asia. It is shown that the growing world population, which is increasingly limited in resources upon the rising demand for animal protein, has stimulated the interest to new food sources that can include insects as future alternative sources of animal protein. In the forming global model based on the growing share of renewable energy sources, entomophagy fits in as a renewable source of food energy. Over the last decade, the potential of edible insects as a new ingredient has been studied. It is noted that edible insects can be produced with less environmental impact compared to cattle. Insects have a huge potential at all life cycle stages as a source of nutritional and active substances and are a rich source of animal protein, contain essential amino acids, minerals (K, Na, Ca, Cu, Fe, Zn, Mn and P), vitamins (В-group, А, D, Е, К and С) and unsaturated fatty acids. Assimilability of insect protein is 76–98%. Insect carbohydrates are represented mainly by chitin contained in a range from 2.7 mg to 49.8 mg/kg of fresh matter. There are data that different insect species can have immune stimulating, sugar reducing, antioxidant and anti-genotoxic activities, as well as the positive effect in cardiovascular and nervous disorders. In the western countries, different methods of insect processing were developed. The review summarizes advantages and risks of eating insects and legal practices of their consumption. Possible ways and strategies of stimulating edible insect consumption are analyzed taking into account that the majority of population in western countries reject the idea of eating insects. The review of performed studies notes the necessity to eliminate emotional and psychological barriers on the way of accepting edible insect consumption.
... They produce less greenhouse gases and ammonia than conventional livestock and use significantly less water. They have high feed conversion efficiency , Palmer 2016 (European Commission 1997), has come into application in the EU. The insect species reported to have the greatest potential for use as food in the EU include Tenebrio molitor, Acheta domesticus, Gryllodes sigillatus, and Bombyx mori (EFSA Scientific Committee 2015). ...
... In contrast, there are few informations about some safety issues, in particular regarding insect protein allergenicity. The structural similarities of insect proteins to known allergens in more widely consumed arthropods present a risk of allergic reactions due to cross-reactivity in individuals with preexisting allergies (Palmer 2016). The tropomyosin, the chitin and the arginine kinase in insects are similar to the ones in crustaceans (Palmer 2016). ...
... The structural similarities of insect proteins to known allergens in more widely consumed arthropods present a risk of allergic reactions due to cross-reactivity in individuals with preexisting allergies (Palmer 2016). The tropomyosin, the chitin and the arginine kinase in insects are similar to the ones in crustaceans (Palmer 2016). As there is no specific treatment for food allergies, strict avoidance of food allergens is the only way to prevent serious health consequences. ...
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On 1 January 2018, a new regulation on ‘Novel Food’ has come into application in the EU. Insects and insect-based products are therefore included among the categories of food which constitute novel foods. Insects are nutrient-rich, produce fewer greenhouse gases and ammonia than conventional livestock, and have high feed conversion efficiency. Insects may be an alternative food source in the near future, but consideration of insects as a food requires scrutiny due to the risk of allergens. The aim of the present study was to develop a set of multiplex polymerase chain reaction (PCR) to detect nine edible insect species directly in foods. Four sets of mPCRs were designed to detect Locusta migratoria migratorioides (Reiche & Fairmaire, 1849) (Orthoptera: Acrididae), Tenebrio molitor (Linnaeus, 1758) (Coleoptera: Tenebrionidae) (mPCR-I), Acheta domesticus (Linnaeus, 1758) (Orthoptera: Gryllidae), Bombyx mori (Linnaeus, 1758) (Lepidoptera: Bombycidae (mPCR-II), Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae), Schistocerca gregaria (Forskål, 1775) (Orthoptera: Acrididae), Zophobas atratus (Fabricius, 1775) (Coleoptera: Tenebrionidae) (mPCR-III), Galleria mellonella (Linnaeus, 1758) (Lepidoptera: Pyralidae), and Gryllodes sigillatus (Walker, 1869) (Orthoptera: Gryllidae) (mPCR-IV). Results demonstrate that the panel of mPCRs allowed a rapid genetic identification of the insect species and has proved to be a sensible and highly discriminatory method. The assay is a potential tool in issues related to the labeling of products and food safety, in case of allergic consumers.
... This procedure, the so-called weight-of-evidence approach, is based on an integrated caseby-case approach. The WHO guidelines for predicting allergenic cross-reactivity suggest a threshold of 35% of sequence identity to a known allergen using a sliding window of 80 amino acids [48•], or a complete identity within an 8 amino acid peptide [49]. An example of allergenicity assumption through sequence alignment analysis is the study of Liu and collaborators [43] on Bombix mori AK. ...
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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. Summary 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 .
... combined with thermal treatment at 55 °C decreased the protein allergenicity by 73.59% as compared to a boiling treatment [52]. However, tropomyosin is usually reported as heat stable and resistant to gastrointestinal digestion [53]. More specifically, it was demonstrated that pepsin could only slightly hydrolyze oyster tropomyosin, which demonstrated that tropomyosin has relatively good resistance to this enzyme. ...
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Edible insects have garnered increased interest as alternative protein sources due to the world’s growing population. However, the allergenicity of specific insect proteins is a major concern for both industry and consumers. This preliminary study investigated the capacity of high hydrostatic pressure (HHP) coupled to enzymatic hydrolysis by Alcalase® or pepsin in order to improve the in vitro digestion of mealworm proteins, specifically allergenic proteins. Pressurization was applied as pretreatment before in vitro digestion or, simultaneously, during hydrolysis. The degree of hydrolysis was compared between the different treatments and a mass spectrometry-based proteomic method was used to determine the efficiency of allergenic protein hydrolysis. Only the Alcalase® hydrolysis under pressure improved the degree of hydrolysis of mealworm proteins. Moreover, the in vitro digestion of the main allergenic proteins was increased by pressurization conditions that were specifically coupled to pepsin hydrolysis. Consequently, HHP-assisted enzymatic hydrolysis represents an alternative strategy to conventional hydrolysis for generating a large amount of peptide originating from allergenic mealworm proteins, and for lowering their immunoreactivity, for food, nutraceutical, and pharmaceutical applications.
... Pong et al. [42] argued that Gregarine spp., a parasite specific to cockroaches, could cause asthma in humans. The results of the survey conducted in our study indicate that insect farming can increase the human exposure to pathogens and allergens [43,44]. ...
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