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Analytical verification of hazelnut in food supports risk-based approaches for proper allergen labeling to prevent unwanted allergic reactions or to quality control diagnostic or therapeutic allergen preparations for allergic subjects. We present the development and validation of a loop-mediated isothermal amplification (LAMP) assay for rapid detection of hazelnut by targeting the internal transcribed spacer 2 gene. The qualitative method requires neither sophisticated analytical equipment nor antibodies, allowing an easy-to-use application with no ethical concern related to the use of animals. It demonstrated a limit of detection at or below 10 mg/kg hazelnut in various food matrices, making it also suitable for verifying hazelnut at levels of clinically relevant eliciting doses. Validation against proficiency test samples and testing of applicability with commercial food items confirmed its usefulness in processed foods. The simplicity of the method, including visual colorimetric detection, combined with high specificity and sensitivity, represents an advancement over existing qualitative methods.

Allergen detection methods support food labeling and quality assessment at the allergen component level of allergen preparations used for allergy diagnosis and immunotherapy (AIT). Commonly applied enzyme-linked immunosorbent assay (ELISA) requires animal antibodies but potentially shows batch variations. We developed synthetic aptamers as alternative binders in allergen detection to meet the replacement, reduction, and refinement (3R) principle on animal protection in science. ssDNA aptamers were specifically selected against the major peanut allergen Ara h 1 and identified by next-generation sequencing. Application in various detection systems (ELISA-like assays, western blot, and surface plasmon resonance) was demonstrated. The ELISA-like assay comprised a sensitivity of 10 ng/mL Ara h 1, comparable to published antibody-based ELISA, and allowed Ara h 1 detection in various peanut flours, similar to those used in peanut AIT as well as in processed food. This ELISA-like aptamer-based assay proofs antibody-free allergen detection for food labeling or quality assessment of diagnostic and therapeutic allergen products.