DETECTION OF BOVINE-MILK IN OVINE MILK BY AN INDIRECT ENZYME-LINKED-IMMUNOSORBENT-ASSAY

An indirect enzyme-linked immunosorbent assay (ELISA) was developed for detection of bovine milk in ovine milk. Polyclonal antibodies were raised in rabbits against bovine whey proteins. Resultant anti-bovine whey protein antibodies were recovered from crude antiserum by immunoadsorption and elution from a column containing bovine whey proteins. Antibodies were biotinylated and rendered specific for bovine milk by mixing them with lyophilized ovine and caprine whey proteins. ExtrAvidin-peroxidase was used to detect the biotinylated anti-bovine whey protein antibodies bound to bovine milk proteins immobilized on 96-well plates. Subsequent enzymic conversion of substrate resulted in discernible differences in optical density between mixtures of ovine milk that contained variable amounts of bovine milk. © 1990, American Dairy Science Association. All rights reserved.