Countercurrent Chromatography (CCC) has the potential to play a major role in food analysis because it permits analysis of crude and complex samples. CCC was evaluated for its ability to separateS. aureusenterotoxin A (SEA), which is a common cause of food poisoning. Mushrooms containing native- or heat-denatured SEA were separated by Toroidal Coil CCC and the fractions containing the toxin were analyzed by Western immunoblotting.