Development and Validation of Immunoassay-based Test for Hazelnut Residue in Food Products

Mohamed M. Abouzied

Neogen Corporation

A 30-minute quantitative Sandwich Enzyme-Linked Immunosorbent assay (S-ELISA) for determination of hazelnut contamination in food products was developed. Polyclonal antibodies against hazelnut specific proteins were produced and used as capture and detector antibodies. Samples were extracted by shaking 5 gram of ground samples with 125 ml of PBS in a hot water bath adjusted to 140°F for 15 minute. Extracts were filtered and filtrates were used directly for ELISA analyses. For quantitative analyses a standard curve ranging from 0 to 25 PPM hazelnut was used. The minimum detection limit for hazelnut was 1ppm. Recovery of hazelnut from various spiked samples varied from 78 to 109 % with a mean recovery of 93 %. The test was validated by performing the following parameters: Limit of detection, cross-reactivity, reproducibility (intra-and inter-assay variability, extraction efficiency (recovery and matrix effect), shelf life stability. The test also went through Alfa Site (internal laboratories) and Beta Site (external laboratories) validation.