Universal Beer Agar

Universal Beer Agar was formulated by Kozulis and Page to isolate and enumerate a wide variety of bacteria and yeast which are encountered in the brewing industry. The selectivity of this agar allows only the growth of these organisms in the presence of hops constituents and alcohol. The addition of beer to the formulation inhibits the growth of transient airborne microorganisms. Tomato Juice Extract is a source of carbon, nitrogenous compounds, and other nutrients. Yeast Extract provides B-complex vitamins, amino acids, and electrolytes. Dextrose and Lactose (contained in Peptonized Milk) are the main fermentable carbohydrates. Di- and Monopotassium Phosphates act as pH buffers. Magnesium, Ferrous and Manganese Sulfates supply essential ions to stimulate metabolism. Sodium Chloride maintains osmotic equilibrium. Agar is the gelifying agent.