Coagulase Mannitol Broth Base is recommended for the simultaneous detection of mannitol fermentation and coagulase production during differentiation of Staphylococci from clinical and non-clinical samples. Colour of the medium changes to yellow due to mannitol fermentation and broth becomes opaque due to coagulation of plasma in case of coagulase positive organisms. Staphylococcus aureus is mannitol and coagulase positive.