Detection of allergens in processed foods: the next analytical challenge

Those of us involved in the food allergen analytical community are constantly striving to improve allergen detection methods. One of the areas of focus in recent years has been to investigate how we can enhance the detection of allergens present in processed foods.

The majority of the food and drink we consume has been processed or modified in some way. This processing brings about many benefits in terms of food safety, preservation and taste. Processing changes the characteristics of the ingredients used to make the food; of particular interest are the changes that can occur to allergenic proteins. Recent studies have shown that the processing of allergens can alter their allergenicity, changing how an allergic individual may react to them. Food allergen analysis is becoming increasingly important as a means to emphasise greater transparency, traceability and integrity in the supply chain. Analysis supports validation and verification of factory cleaning and investigation of recalls and incidents.

Immunoassay based food allergen detection methods rely on the use of antibodies to detect allergens present in food. It follows that such detection may be effected by processing. Allergenic proteins can be subject to heat-accelerated chemical reactions including Maillard reactions and other protein-carbohydrate interactions, protein aggregation with loss of solubility, shear effects on protein structure, emulsion formation, pH effects and water activity considerations during food production. Such processing effects must be taken into account when developing new analytical methods, either by improved extraction methods to try to increase the solubility of the aggregated proteins or by going back to basics and raising new sets of antibodies that specifically target processed allergens.

In order to evaluate these new allergen detection methods, incurred sample controls are needed. These are defined as samples in which a known amount of the food allergen has been incorporated during processing, mimicking as closely as possible the actual conditions under which the sample matrix would normally be manufactured. The real life sample would give the most accurate representation of the recovery and response of a particular method for that particular matrix.

Incurred sample controls and immunoassays that can reliably detect processed allergens are key to being able to fully support the food industry with their future analytical needs.


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This article was originally published as part of the Allergen In-Depth-Focus 2017 in the June issue of New Food Magazine.