Detection and quantification of goat's cheese in ewe's cheese using a monoclonal antibody and two ELISA formats

A stable hybridoma cell line (B2B) has been produced secreting a monoclonal antibody (MAb) specific for the s αs2-casein of goats. The MAb B2B was used in two enzyme-linked immunosorbent assays (ELISA) formats for the detection and quantification of the presence of goat's cheese in ewe's cheese samples. In the indirect ELISA format the limit of detection was 1–25% (w/w) substitution of ewe's cheese samples by goat's cheese. Afterwards, a competitive indirect ELISA was successfully developed for the detection of 0.5 to 25% (w/w) of goat's cheese in ewe's cheese samples. This competitive indirect ELISA is a very sensitive assay, can be performed in less than 5 h and is not influenced by the ripening process in cheese.