High grade EMB (eosin methylene blue) agar is supplied by Micromaster. It is available in the form of a pink solid which has a peptone-like odour. It is a blend of two stains, eosin and methylene blue in the ratio of 6:1. It is stable if stored according to the recommended conditions. If exposed to excessive heat or in case of burning, it can generate hazardous decomposition products like chlorine and phosphorous oxide. It is incompatible with oxidising agents.

Quantity provided: 100 g/pack

EMB agar is used as a differential microbiological medium, which slightly inhibits the growth of Gram-positive bacteria and provides a colour indicator distinguishing between organisms that ferment lactose (e.g., E. coli) and those that do not (e.g., Salmonella, Shigella). Organisms that ferment lactose display "nucleated colonies which are colonies with dark centres. This medium is important in medical laboratories as it can help in distinguishing pathogenic microbes in a short period of time. Vigorous fermenters of lactose or sucrose will produce quantities of acid sufficient to form the dark purple dye complex. The growth of these organisms will appear dark purple to black. Escherichia coli, a vigorous fermenter, often produces a green metallic sheen. Slow or weak fermenters will produce mucoid pink colonies. Normally-colored or colorless colonies indicate that the organism ferments neither lactose nor sucrose and is not a fecal coliform. Sucrose and lactose, present in this medium, serve as fermentable carbohydrate sources which encourage the growth of fecal coliforms and provide a means of differentiating them.