Comparative study of commercially available gluten elisa kits using an incurred reference material

Abstract

Handling major hypersensitivity reactions (e.g. celiac disease) triggered by proteins of wheat and other cereals is a challenging task for healthcare systems, legislative forces and the related fields of food analysis as well. In spite of the fact that there are available official threshold levels for labelling the absence of gluten, which is considered to be the toxic protein fraction of wheat, barley and rye, validation of the analytical methodology supporting regulatory requirements is currently problematic. The main limiting factors of method validation are the lack of reference methods and reference materials. The objective of this study was to provide a solution to this problem. An incurred reference material in a model food matrix was developed and studied by commercially available ELISA test kits as a part of the activity of the Food Allergen Working Group within the FP6 funded EU project MoniQA. After successful completion of the reference material development process, the incurred material was used as a basis of a comparative study examining the performance and applicability of seven commercially available ELISA kits designed for quantification of gluten/gliadin. In certain cases the obtained data showed discrepancies from the expected gliadin content that may carry both a food safety and an economic relevance. The evaluation of the effects of heat treatment on the analytical results is also presented, highlighting the fact that the food processing steps may have a considerable impact on the analytical data, thus should be carefully handled during method development and validation. © 2013 Wageningen Academic Publishers.