m-Green Yeast & Mold Broth is used for the detection of yeast and fungi in the routine analysis of beverages. Enzymatic Digests of Casein and Animal Tissue provide nitrogenous compounds and carbon sources. Yeast Extract is a source of B-complex vitamins. Dextrose is the fermentable carbohydrate. Potassium Phosphate serves as buffering agent. Magnesium Sulfate, Thiamine, and Diastase (a mixture containing amylolytic enzymes) provide essential ions, minerals, and nutrients. The green pH indicator Bromocresol Green diffuses into the colonies. Acidic products from fungal metabolism diffuse into the medium, further lowering the pH and causing the indicator to turn yellow around the colonies. In this medium, the low pH inhibits the growth of bacteria.