A recent online seminar has presented a summary of the UK Food Standards Agency’s 2022 commissioned review of food allergen detection methods. The report and seminar offer guidance on how and where to apply certain analytical approaches to ensure accurate identification of priority allergens in food products.
The most widely used method, Enzyme-Linked Immunosorbent Assay (ELISA), detects allergenic proteins using antibodies. Monoclonal antibodies offer specificity, reducing cross-reactivity, while polyclonal antibodies increase detection likelihood in processed foods but risk false positives. ELISA kits differ significantly in performance, with some failing to specify target proteins or validation matrices, leading to unreliable results. For example, ovalbumin in eggs becomes undetectable after thermal processing, while ovalmucoid remains stable, highlighting the importance of knowing which protein a kit targets.
Polymerase Chain Reaction (PCR) is used as a confirmatory method, amplifying DNA to infer the presence of allergens. However, it cannot detect proteins directly and is not usually suitable for detecting certain allergens where DNA is either absent or indistinguishable from other sources. Despite its limitations, PCR performs well with some processed foods where ELISA may fail.
Mass spectrometry (MS) is an emerging technique offering high specificity by identifying unique peptide sequences. It has shown promise in detecting allergens like peanuts and mustard at very low levels. However, MS methods require further refinement to match ELISA’s sensitivity and need broader validation across food types.
To improve allergen detection, the review recommended future efforts focus on developing multi-allergen tests, validating methods across diverse food matrices, and establishing open-access databases for cross-reactivity and kit performance. Industry-wide standards for testing thresholds and procedures, along with increased supply chain auditing, will enhance reliability and transparency.
The FSA review of allergen analytical testing methodologies is available here. A recording of the July 2025 online seminar can be viewed on You Tube.
