A dot blot enzyme immunoassay was developed for detection of peanut proteins in foods based on the use of polyester cloth as the solid phase. Samples were spotted on polyester cloth pre-coated with anti-peanut antibodies (chicken IgY), and bound peanut proteins were detected by sequential reactions with peroxidase-conjugated anti-peanut antibodies and chromogenic substrate. This assay detected peanut proteins in a variety of foods, in some instances giving positive results with samples containing less than 1 ppm peanut protein.