Towards comparability of ELISA results for peanut proteins in food: A feasibility study

Results from different enzyme-linked immunosorbent assays (ELISAs) for the detection of peanut protein in food lack comparability due to different measurands, extraction procedures, antibodies, detection systems, and calibrants. Therefore, a feasibility study on a suitable quality control material (QCM) was conducted. A peanut powder and a non-de-fatted peanut homogenate were produced, and the materials properties including homogeneity and stability were assessed. Additionally, the influence of the extraction buffer on the protein yield and composition was investigated. A set of methods was applied including two ELISAs, SDS–PAGE, a “total soluble protein” assay, a “total fat” method, and a photometric assay to detect fat oxidation. Both preparations were sufficiently homogeneous for the intended use, and storage at 40 °C for up to 3 months did not reveal any material degradation. The extraction buffer influences the protein yield, but not the composition of the extracted proteins. The results constitute an important step towards the development of a peanut protein QCM.