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Foodborne diseases are becoming major scientific struggles for both developing and developed countries. Most foodborne infections are caused by microbial pathogens such as bacteria, viruses, and other food allergens. Hence early and accurate diagnosis of these foodborne pathogens is always preferable. To satisfy these concerns, plenty of isothermal amplification methodologies such as rolling circle amplification (RCA), helicase-dependent amplification (HDA), and recombinase polymerase amplification (RPA) have been developed. Among these, loop-mediated isothermal amplification (LAMP) is a widely usable, potential, and recognizable amplification technique achieved at a constant temperature around 60°C within 30–60 min by using only one kind of enzyme. As a robust gene amplification technique, it can be employed for the detection of bacteria, viruses, and other related food allergens. This technique has its own merits such as cost-effectiveness, facile manufacturing procedure, and consistency. In this chapter, we emphasize recent trends in designing the techniques, challenges, and the future prospects of LAMP in the detection of foodborne pathogens. These effective pathogen detection methods may offer potential benefits compared with existing conventional methods.

Food allergy is a large and growing public health problem in many areas of the world. The prevalence of food allergy has increased in the last decades in a very significant way in many world regions, particularly in developed countries. In that respect, the research field of food allergy has experienced an extensive growth and very relevant progress has been made in recent years regarding the characterization of food allergens, the study of their immunological properties, and their detection in food sources. Furthermore, food labeling policies have also been improved decidedly in recent years. For that immense progress made, it is about time to review the latest progress in the field of food allergy. In this review, we intend to carry out an extensive and profound overview regarding the latest scientific advances and knowledge in the field of food allergen detection, characterization, and in the study of the effects of food processing on the physico-chemical properties of food allergens. The advances in food labeling policies, and methodologies for the characterization of food allergens are also thoroughly reviewed in the present overview.

Food allergy (FA) is a relatively new food safety issue with an increasing prevalence worldwide and an increasing number of food allergens identified. It is due to an anomalous interaction between food components and immune system causing a broad spectrum of disorders extremely variable among individuals. Although FA-related diseases are restricted to a small category of individuals, the number of patients concerned is continuously growing in the last 10 years, making this field of a primary importance for clinicians as well as for food industry. Several foods are implicated in allergic reactions; however, a total of eight big ingredients have been identified accounting for most of the allergic reactions, that is, milk, egg, wheat, soy, peanuts, tree nuts (e.g., hazelnut, walnuts, pecans, almonds, and cashews), fish, and shellfish. This chapter illustrates the capabilities and potential of MS applied to the detection of allergens in food. Top-down and bottom-up approaches are presented. Finally, performances of high and low-resolution mass spectrometry to meet the desired allergen thresholds are presented.

Food allergies continue to cause disruptions to various military strategic plans because of the discomfort they cause to one or critical members of armed forces in the barracks, on the desk as well as in the field. The incapacitation of personnel at various degrees can never be underestimated as it may cost the army’s overall objectives. Phytochemicals present some hope to the army’s research and development unit in terms of the potential to develop prophylaxes, drugs, and other therapeutic products upon appropriate scientific standardization and optimization at molecular levels. Understanding the biochemistry and mechanisms of action of these phytochemicals in all fronts paves the way to a reliable therapeutic discovery. It is therefore important to consider the inclusion of phytomedicine in the army for the wellbeing of service personnel.

Since 2–3 decades, food allergies seem to have increased in prevalence. They remain more common in children compared to adults, but some of them have a high rate of resolution in childhood. If peanut, tree nuts, fish, shellfish, egg, milk, wheat, soy and seeds account for the most serious allergic reaction and are acknowledged as being of public health importance; fish, shellfish, tree nuts, peanuts and seeds have a poor rate of rate of resolution in childhood. This article will discuss the prevalence, the symptoms, the eliciting dose, the characteristic allergenic proteins, the potential cross-reactivity of proteins and the potential treatment advances for three persistent food allergies: seafood, tree nuts and peanut. It will conclude with few words regarding VITAL (Voluntary Incidental Trace Allergen Labelling) risk assessment system, the development of reference material and the harmonization of suitable methodologies for the detection of these food allergens.

Contemporary humans spend most of their time indoors. Indoor environments are rich in aerosolized and particulate organic and inorganic matter, which may differ according to the type of indoor environment (house, school, working place, sport facility, transportation), outdoor input and human activities. Interaction of airborne substances with the immune system may result in irritant, toxic, and sensitizing effects. In this article, we will review indoor environmental allergens defined as airborne substances that upon inhalation or mucocutaneous exposure may interact with the immune system and lead to sensitization and allergic disease.

PURPOSE OF REVIEW: Molecular allergology uses pure, mainly recombinant and structurally defined allergen molecules and allergen-derived epitopes to study mechanisms of IgE-associated allergy, to diagnose, and even predict the development of allergic manifestations and to treat and prevent IgE-associated allergies. Atopic dermatitis, a chronic inflammatory skin disease is almost always associated with IgE sensitization to allergens. However, also non-IgE-mediated pathomechanisms seem to be operative in atopic dermatitis and it is often difficult to identify the disease-causing allergens. Here we review recent work showing the usefulness of molecular allergology to study mechanisms of atopic dermatitis, for diagnosis and eventually for treatment and prevention of atopic dermatitis. RECENT FINDINGS: IgE sensitization to airborne, food-derived, microbial allergens, and autoallergens has been found to be associated with atopic dermatitis. Using defined allergen molecules and non-IgE-reactive allergen derivatives, evidence could be provided for the existence of IgE- and non-IgE-mediated mechanisms of inflammation in atopic dermatitis. Furthermore, effects of epicutaneous allergen administration on systemic allergen-specific immune responses have been studied. Multi-allergen tests containing micro-arrayed allergen molecules have been shown to be useful for the identification of culprit allergens in atopic dermatitis and may improve the management of atopic dermatitis by allergen-specific immunotherapy, allergen avoidance, and IgE-targeting therapies in a personalized medicine approach. SUMMARY: Molecular allergology allows for dissection of the pathomechanisms of atopic dermatitis, provides new forms of allergy diagnosis for identification of disease-causing allergens, and opens the door to new forms of management by allergen-specific and T cells-targeting or IgE-targeting interventions in a personalized medicine approach.

Food allergy is an abnormal immunological, usually immunoglobulin E–related, reaction resulting from exposure through ingestion of, skin contact with, or inhalation of exogenous food macromolecules (typically proteins) known as allergens or antigens. Until now, avoidance of food has been practiced by allergic patients to protect themselves from this health problem. However, with the number of novel food products and ingredients launched on the market by the industry, it is a challenge for allergic patients to keep track of all the ingredients in the food products. In addition, cross-contamination of food allergens from one product to another and mislabeling pose health risks and sometimes can be fatal to allergic patients. A number of thermal and nonthermal food processing interventions have been tested on various allergenic foods to reduce their allergenicity. However, complicated food matrices and varied detection methods make it very challenging to apply a particular technology for reducing allergenicity. This chapter highlights the application of ultrasound to the potential reduction of food allergenicity.

Allergy is a widespread disease effective 10%–20% of the general population all around the world. Allergies are chronic illnesses caused by the exposure of the respiratory system to dust or pollen, the skin to chemical materials, or the digestion system to particular foods. Immunoglobulin E (IgE) antibody plays a very important role in the development of allergies in humans. The high level of total IgE in human serum reflects the presence of allergic conditions. Test kits for commercially available serum IgE measurements are based on conventional immunoassay techniques. These techniques include time-consuming procedures, expensive instruments, and hazardous labels. Currently, molecularly imprinted polymer-based sensors are utilized as an alternative artificial receptor. MIP-based sensor systems for biological applications have been widely utilized in works on biomolecular interactions, with the change in sensor signals. Herein, the development of rapid, easy-to-use and cost-effective allergen detection methods based on mass sensitive, optic, electrochemical, and nanomaterials based sensors have been reported. Finally, we present sensor systems were investigated with a molecular imprinting technique for the detection of allergens as a marker of various allergies.

Food allergies are the most common allergic disease among the human population. A fast and accurate method for detecting allergens in food is therefore important. This chapter introduces an optical thin film biochips assay for detection of allergens in food and food materials. The principles of optical thin film biochips and their application are described and the advantages and disadvantages of this assay are compared with those of with other methods also discussed. As a high-throughput detection method, the optical thin film biochips assay has the potential to become useful tool to detect food allergens in laboratories ranging from the sophisticated to the poorly equipped.

Sampling is a critical part of analytical testing for food allergens. This chapter looks at the reasons for taking samples for food allergens, including law enforcement, surveillance, allergen management control and assessment of the performance of analytical methods, and at the factors involved in drawing up a sampling plan. Different approaches to sampling are then discussed, including representative, selective, random and composite sampling. Sample types are examined, looking at food samples, at rinse water, wash water and flushing materials, settle plates and swabbing. The chapter finishes by looking at sample quality issues, relating to possible contamination, traceability, and stability, before indicating some possible future trends in this field.

Background: Food allergies are a significant public health issue and the only effective management option currently available is strict avoidance of all foods containing the allergen. In view of the practical impossibility to limit risks to zero, quantitative allergen risk assessment and management strategies are needed. Objective: To develop appropriate methods for informing population-based risk assessments and risk management programs to benefit all stakeholders, but particularly food allergic individuals. Methods: Individual thresholds for food allergens (maximum tolerable doses and minimum eliciting doses) can ideally be established through double-blind, placebo-controlled food challenges (DBPCFCs). If DBPCFC data is not available, data from widely used “open” food challenges (OFCs) using pre-defined objective criteria can also provide useful data regarding minimum eliciting doses. For more than 20 years, the Netherlands Organisation for Applied Scientific Research (TNO) and The Food Allergy Research and Resource Program (FARRP) at the University of Nebraska-Lincoln have been collecting individual maximum tolerable doses and minimum eliciting doses that produce objective symptoms from published and unpublished clinical data to better refine knowledge regarding the sensitivity of the population to food allergens. Results: In this paper we provide in depth insights into the methodology applied by TNO and FARRP to derive individual maximum tolerable doses and minimum eliciting doses for objective symptoms from clinical food challenge data. Over 90 examples for determining the individual allergic thresholds are presented. Conclusion: With the methodology presented in this paper, we aim to stimulate harmonization and transparency in quantitative food allergen risk assessment and risk management programs, encouraging their wider adoption.

Environmental allergens, such as pollens and house dust mite allergens, cause sensitization and lead to allergic diseases, which make people suffer from asthma or rhinitis. These environmental allergens often become airborne in a living space, and residents are endangered to be exposed to and inhale the airborne allergens. Therefore, prevention of the exposure directly connects to prevention of allergic diseases. One of the possible ways to avoid the exposure is monitoring of airborne allergens in a living space and making a resident become aware of the environmental quality. Such a system requires a sensor, and especially with high selectivity along with a sensitivity to the allergens. For this purpose, immunosensors are the candidates due to their high selectivity, which relies on the specificity of an antibody. A challenge to use immunosensors for monitoring is difficulty of sensor surface regeneration—breaking down a formed immunocomplex and removing them from the sensor surface for a next measurement. In this chapter, we describe a reusable immunosensor for monitoring of a HDM allergen, Dermatophagoides farinae group 1 (Der f 1). The immunosensor utilizes a surface acoustic wave device and surface modification with pH-tolerant protein scaffold (ORLA85 protein) for capture antibody immobilization. Der f 1 is measured by detecting viscoelastic change induced by sandwich assay with detection antibodies. In addition, the use of gold nanoparticles for amplification of the sensor’s output signal is also discussed.

A review of cockroach allergen and its role in allergic disease is presented. Relationships among cockroach allergen exposure, allergic sensitization, and disease are described, prevalence and exposure risk are characterized, and research on reducing exposures is discussed. Studies have demonstrated that the combination of sensitization and exposure to cockroach allergens is associated with asthma morbidity, and some have concluded that levels of cockroach allergen in homes may be one of the strongest risk factors predictive of allergic sensitization and asthma morbidity in children. Other research has found that cockroach allergens are detectable in most homes in the United States and many other regions. The prevalence of cockroach allergens is particularly high in urban areas and low-income settings, but is not limited to these environments as studies have found cockroach exposure and sensitization in suburban and rural areas as well. Practical measures to reduce environmental exposures have had mixed success; many have achieved reductions in cockroach populations, but not a corresponding, sustained reduction in allergen exposure. However, a few studies have achieved a sustained reduction in allergen levels through sophisticated cockroach eradication measures. It remains of interest to demonstrate associated improvements in asthma morbidity.

Enzyme-linked immunosorbent assays (ELISA) are effective methods for the determination of antigens in defined matrices. The method is routinely used today in clinical chemistry as well as in food analysis. It offers the possibility to measure small amounts of analytes like mycotoxins, pesticides and vitamins as well as food allergens in different food matrices. This chapter discusses key terms of the method and the main components which are required. Furthermore, it describes possible extraction procedures of the measurands from food. Finally, quality parameters for the method are discussed.

Food allergy is a growing public health concern. Patients suffering from food allergies need to avoid the offending food in order to avoid getting an allergic response. There is a need for a quick, cheap and reliable point-of-care (POC) sensor for household use and for industry use. Surface plasmon resonance (SPR) is an upcoming technique in the food allergen field. It has shown great potential for studying biomolecular interactions without extensive sample preparations such as the removal of excess reactants in sample solutions. Food sample preparation will be reduced to a minimum. Furthermore, this method is very sensitive and able to detect also trace amounts of food allergens.

With increasing reports of allergy cases caused by mustard and sesame, these two minor food ingredients are attracting increasing attention because of their popularity as seasoning material worldwide. In this chapter, research on allergen proteins of mustard and sesame is overviewed and reported detection methods aiming at allergen proteins or genes of mustard and sesame are summarized, including the status quo of commercial testing reagents. The advantages and drawbacks of these methods are also discussed, which would be helpful for developing faster, more sensitive and economical methods for mustard and sesame detection in the future.

Hen egg white comprises of a complex mixture of proteins, which greatly differ in their physicochemical characteristics and relative abundance. We aimed to identify potential undiscovered egg allergens within the egg white proteome and investigated the existence of matrix effects on the proteolytic stability and resultant IgE-binding of the allergenic proteins. In addition to the main egg allergens: ovalbumin (OVA), ovomucoid (OM) and lysozyme (LYS), two minor egg white proteins, tentatively identified as ovoinhibitor and clusterin, were found to react with serum IgE from egg-allergic patients. Egg white exhibited residual immunoreactivity after gastrointestinal digestion due to the presence of intact OVA and LYS, as well as of several IgE-binding peptides derived from OVA. The presence of egg yolk slightly increased the susceptibility to hydrolysis of egg white proteins and abrogated bile salt-induced precipitation of LYS in the duodenal medium. However, the resultant immunoreactivity against IgE of egg white proteins after in vitro digestion was not significantly modified by the presence of yolk components. © 2012 Elsevier Ltd. All rights reserved., This work was supported by Projects AGL2008-01740 and AGL2011-24740. We also acknowledge CYTED P109AC-0302 and COST ACTION Infogest FA1005. G. M. is in receipt of a JAE-CSIC Ph. D. fellowship.

Proteins are ubiquitous and contribute to the technofunctional characteristics of several foods, and also serve as nutrients. However, some dietary proteins are allergens and their presence and immunological mechanisms can elicit acute response in sensitized/allergic individuals. Allergenic foods include foods from both plants and animals such as peanuts, tree nuts, wheat, soy, cow's milk, eggs, fish, and shellfish. A sizeable number of the human population is hypersensitive to immunoglobulin E (IgE)-mediated reactions and some form of food allergy, which affects their lifestyle. During the course of food processing, cross-contamination and changes in protein structure and conformation may affect their physicochemical properties and induce allergenicity. Both conformational and linear epitopes and interaction of food proteins with other ingredients may be affected by processing. These processes can lead to secondary and tertiary structure modifications and response of IgE immune system by reducing intramolecular disulfide bonds of the proteins and epitope accessibility through destruction or masking. Nonetheless, some allergens are stable to processing and it is imperative to select effective processing methods and parameters to reduce allergenicity without contributing to the formation of neoallergens (new allergenic epitopes) or increased allergenic potential. The efficacy of the deactivation technique can be established by reliable detection and identification methods. For both established and new protein sources, the need to establish their safety and threshold levels in food products are important to consumers, food manufacturers, and public health and regulatory agencies. Efforts are needed to provide food composition information with the declared allergenic ingredients or the presence of traces of allergens due to contamination or that formed during food processing, present allowable limits in the products, and determine if a manufactured food is safe for consumption. This chapter describes the current and emerging techniques for detecting and deactivating food allergens.

Although any foodstuffs containing protein can be allergenic, it is generally accepted that there are a small number of key foods that are responsible for the majority of the food allergy public health burden. While some of these foods, such as cows’ milk, hens’ eggs, and peanuts, are seen to be of significant concern in many countries around the world, others are of concern only in restricted geographical areas. The need for, and evolution of, specific regulations on labeling of allergenic food ingredients building on general ingredients listing legislative requirements is explained, concentrating on the situation in the European Union. Legislative controls on the labeling of foods for people with gluten intolerance are also described, as are other aspects of food allergen labeling not currently covered by legislation, particularly the use of precautionary warning labeling of the risks of allergen cross contamination.

Immunoproteomics, IgE-inhibition assays and cDNA-cloning reveals that ash and olive allergenic protein profiles are mostly equivalent, thus explaining their high cross reactivity. Our data suggest simplifying diagnosis of patients by using indistinctly ash or olive pollen.

Indoor and outdoor allergen sources contain several allergens. The majority are proteinaceous, although carbohydrate epitopes, particularly α-Gal, may be significant. The most important outdoor allergens are derived from the pollens and fungal spores, and phylogenetically-related species produce similar spectra of allergens. Although no unifying structural feature determines allergenicity, the biochemistry of allergens, as well as their association with non-allergen derived components may be significant. Indoor allergens are derived from dust mites, pets, cockroaches and rodents. Submicronic allergen-containing particles will penetrate into the lung and remain airborne for longer periods compared with larger particles, which will be trapped in the upper airways. Allergen avoidance can be an effective countermeasure for asthma, perennial rhinitis, and atopic dermatitis but compliance and sufficient allergen reduction may be difficult. Air pollution may occur both indoors and outdoors and exacerbate asthma symptoms, as well as contribute to the development of disease through direct, non-allergic, effects or by interactions with allergens per se .

This paper reviews the in vitro digestion models developed to assess the stability digestion of food allergens, as well as the factors derived from the methodology and food structure that may affect the assay results. The adequacy of using the digestion stability of food allergens as a criterion for assessing potential allergenicity is also discussed. Data based on the traditional pepsin digestibility test in simulated gastric fluid are discussed in detail, with special attention to the influence of the pH and pepsin: allergen ratio in the pepsinolysis rate. This review points out the importance of using physiologically relevant in vitro digestion systems for evaluating digestibility of allergens. This would imply the sequential use of digestive enzymes in physiological concentrations, simulation of the stomach/small intestine environment (multi-phase models) with addition of surfactants such as phospholipids or bile salts, as well as the consideration of the gastrointestinal transit and the effect of the food matrices on the allergen digestion and subsequent absorption through the intestinal mucosa. In vitro gastrointestinal digestion protocols should be preferably combined with immunological assays in order to elucidate the role of large digestion-resistant fragments and the influence of the food matrix on the stimulation of the immune system., This work was supported by the European Union (Project MERG-CT-2004-01170) and the CSIC-Comunidad de Madrid (Project 200570M066). F.J.M. is recipient of an I3P-CSIC contract.

Publisher Summary This chapter discusses the status and future potential of plant biotechnology in reducing allergens in food. Food allergic reactions affect 6-8% of children and 1-2% of the adult population. Many allergic reactions are to plant origin, including peanuts, soy, wheat, and tree nuts. Allergic reactions are typically elicited by a defined subset of proteins that are found in abundance in food. The increased prevalence of allergic reactions coupled with severe clinical symptoms has led many scientists to explore methods of reducing allergenicity of some crops. This chapter explores the potential of reducing the allergenicity of plants used as food crops by both traditionally breeding practices and genetic engineering methods. The chapter reviews how biotechnology began and progressed, the uses of biotechnology and points out its uses in decreasing levels of known allergens or their allergenicity. The characteristics of food allergens are first explored. Traditional plant breeding methods for reducing allergenicity are discussed. Use of genetic engineering to reduce allergenic potential is also described focusing on post-transcriptional gene silencing, reduction of disulfide bonds by thioredoxin, and modification of genes encoding allergens.

The intestinal tract and lung represent large surface areas of the body in which there is continuous contact with an array of ingested or inhaled antigens and microorganisms. The induction of physiological tolerance to harmless antigens and commensal microorganisms is vital to avoid unwarranted excessive inflammation; yet, the ability to mount efficient inflammatory responses to pathogens remains important. This dynamic balance between tolerance to allergens and commensal microorganisms versus inflammatory responses to pathogens is coordinately regulated by innate and adaptive components of the mucosal immune system. Interactions among epithelial cells, antigen-presenting cells, and induced regulatory T cells (iTreg) mediate the development of physiological tolerance, with iTreg playing a critical role. This chapter describes the mechanisms that mediate physiological tolerance to ingested and inhaled allergens.

Helminth infections and allergic diseases elicit strong Th2 responses. The up-regulation of IL-4, IL-13, IL-5, IL-9, total IgE, eosinophils and macrophages are part of the host immune response against helminths and also compose an immunological pattern that accompanies allergic diseases. These facts together with the common features observed between allergens and parasite antigens suggest that the immune response to helminths and allergy could have developed under the same evolutionary process. However, asthma can have a positive or negative association with helminth infections, depending on several factors, such as the helminth species, the clinical status of infection, host genetics, or intensity of infection. The model of immune regulation observed in helminths can be very useful for developing alternative strategies for the prevention, treatment, and control of inflammatory diseases including allergic diseases. Helminth infections induce a complex immune regulatory network that utilizes dendritic cells, Treg cells and systematic elevated levels of IL-10 and possibly TGF-β, B reg cells and activated macrophages to achieve chronic asymptomatic conditions that can be used as a model to design the aforementioned strategies.

IgE antibodies circulate in the blood of individuals sensitized to food allergens. This chapter overviews in vivo and in vitro assays that employ human IgE antibodies as reagents for the detection and quantification of select allergens in extracts of foods. More specifically, judicious application of dilutions of physiological food extracts into the skin of humans known to be allergic to a specific food allows detection and semi-quantitative measurement of the allergen in food extracts. Alternatively, human serum containing IgE antibodies to known food allergens can be used as reagents in a competitive inhibition allergosorbent assay to quantify allergen in unknown food extracts. Performance characteristics, assay limitations and assay quality control are discussed for in vivo and in vitro assays.

The chapter focuses on how a retailer can approach allergen management across its business and how to go about achieving a consistent approach across the supply base. It shows how allergens on site are risk assessed using a simple step by step process. It then focuses on factory standards and controls within different factory environments. Different allergens in the food chain are identified and their risk management is discussed. The chapter also describes the evolution of a food labelling system within an organisation and how to reduce the risk to consumers via the participation of suppliers in allergen identification and labelling.