Trypto Soy Broth with Casamino Acids is a liquid medium used for the selective enrichment of enterohemorrhagic E. coli in foods. Enzymatic Digest of Casein, Acid Hydrolyzed Casein, and Soy Peptone provide nitrogen, vitamins, and minerals to stimulate growth. Sodium Chloride maintains the osmotic balance of the medium. Dipotassium Phosphate is the buffering agent. Dextrose is the carbon energy source. Bile Salts No. 3 and Novobiocin (added where indicated by the procedure requirements) are used as selective agents to inhibit bacterial growth.