Accidental food allergy reactions: Products and undeclared ingredients.

BACKGROUND: Accidental allergic reactions to food are frequent and can be severe and even fatal. OBJECTIVE: We sought to analyze the culprit food products and levels of unexpected allergens in accidental reactions. METHODS: A prospective cohort study was conducted in adults (n = 157) with a physician-confirmed diagnosis of food allergy. During a 1-year follow-up, 73 patients reported accidental allergic reactions and the culprit food products. Food samples received (n = 51) were analyzed for a wide range of suspected noningredient allergens, and risk was quantified. RESULTS: A very diverse range of food products was responsible for the unexpected allergic reactions. Thirty-seven percent (19/51) of products analyzed had 1 to 4 culprit allergens identified that were not supposed to be present according to the ingredient declaration. Concentrations varied from 1 to 5000 mg of protein of the allergenic food per kilogram of food product and were greatest for peanut, milk, and sesame. Milk proteins posed the highest estimated risk for objective allergic reactions. The intake of culprit allergens by patients varied considerably. For those cases in which culprit allergens were detected, the intake of at least 1 allergen exceeded the reference dose or a culprit allergen with a yet unknown reference dose was present. Both patient neglect of precautionary allergen labeling statements and omission of using a precautionary allergen labeling statement by food manufacturers seem to contribute to accidental reactions. CONCLUSION: A wide range of food products are causing accidental reactions in patients with food allergy. Eight different allergens not declared on the ingredient lists were detected in the culprit food products, all of which were representative of allergens regulated in the European Union.

Detection of ruminant meat and bone meals in animal feed by real-time polymerase chain reaction: result of an interlaboratory study.

The commercialization of animal feeds infected by prions proved to be the main cause of transmission of bovine spongiform encephalopathy (BSE). Therefore, feed bans were enforced, initially for ruminant feeds, and later for all feeds for farmed animals. The development and validation of analytical methods for the species-specific detection of animal proteins in animal feed has been indicated in the TSE (Transmissible Spongiform Encephalopathies) Roadmap (European Commission. The TSE (Transmissible Spongiform Encephalopathy) roadmap. URL: http://europa.eu.int/comm/food/food/biosafety/bse/roadmap_en.pdf, 2005) as the main condition for lifting the extended feed ban. Methods based on polymerase chain reaction (PCR) seem to be a promising solution for this aim. The main objective of this study was to determine the applicability of four different real-time PCR methods, developed by three National expert laboratories from the European Union (EU), for the detection and identification of cattle or ruminant species in typical compound feeds, fortified with meat and bone meals (MBM) from different animal species at different concentration levels. The MBM samples utilized in this study have been treated using the sterilization condition mandatory within the European Union (steam pressure sterilization at 133 degrees C, 3 bar, and 20 min), which is an additional challenge to the PCR methods evaluated in this study. The results indicate that the three labs applying their PCR methods were able to detect 0.1% of cattle MBM, either alone or in mixtures with different materials such as fishmeal, which demonstrates the improvement made by this technique, especially when compared with results from former interlaboratory studies.

Development of an enzyme-linked immunosorbent assay method to detect mustard protein in mustard seed oil.

An enzyme-linked immunosorbent assay for the detection of mustard protein was developed. The assay is based on a polyclonal antiserum directed against a mixture of mustard proteins raised in rabbits. The assay has a detection limit of 1.5 ppm (milligrams per kilogram) and is suitable for the detection of traces of mustard protein in mustard seed-derived flavoring ingredients. Limited cross-reactivity testing showed that no other plant proteins reacted significantly. From the animal proteins tested, only milk showed some cross-reactivity. With this sensitive assay, it was shown that refined mustard seed oil produced by steam distillation does not contain detectable amounts of mustard protein. Mustard seed oil is used as a flavoring in very low quantities, typically between 40 and 200 mg/kg. Thus, 100 g of a food product flavored with 200 mg of mustard seed oil per kg containing < 1.5 mg of protein per kg would represent an amount of mustard seed protein of <30 ng. Taking into account the published literature on allergic reactions to the unintended ingestion of mustard, this conservatively low calculated level indicates that it is unlikely that food products containing mustard seed oil as a flavoring ingredient will elicit an allergic reaction in mustard-allergic individuals.

Detection of genetically modified organisms in foods by protein- and DNA-based techniques: bridging the methods.

According to European Commission (EC) Regulation 1139/98, foods and food ingredients that are to be delivered to the final consumer in which either protein or DNA resulting from genetic modification is present, shall be subject to additional specific labeling requirements. Since 1994, genetically altered tomatoes, squash, potatoes, canola, cotton, and soy have been on the market. Recently, insect-resistant and herbicide-tolerant maize varieties have been introduced. Soy and maize are 2 of the most important vegetable crops in the world. During the past 4 years, both protein- and DNA-based methods have been developed and applied for detection of transgenic soy and maize, and their derivatives. For protein-based detection, specific monoclonal and polyclonal antibodies have been developed; for immunochemical detection, Western blot analysis and enzyme-linked immunosorbent assays are the most prominent examples. For detection of genetically modified organisms (GMOs) at the level of DNA, polymerase chain reaction-based methods are mainly used. For these reactions, highly specific primer sets are needed. This study compares the principally different methods. Specificity of methods and the possible risks of false-positive or false-negative results are considered in relation to sampling, matrix effects, and food processing procedures. In addition, quantitative aspects of protein- and DNA-based GM detection methods are presented and discussed. This is especially relevant as EC regulation 49/2000, which defines a threshold for an unintentional comingling of 1%, came into force on April 10, 2000.