Product Number: 2428350
M-green Yeast and Mold is a membrane filtration method for the detection of yeast and fungi in beverages. This medium has a low pH, which inhibits bacterial growth. Bromocresol green indicates pH change: yellow (acid reaction), green (alkaline reaction). When bromocresol green diffuses into fungal colonies it has an alkaline reaction, allowing easily identification. Metabolic by-products from the developing colonies diffuse into the surrounding medium, further reducing the pH which aids in the inhibition of bacterial growth, but also produces an acid reaction which causes residual bromocresol green to change to yellow.
Mold colonies will have a fuzzy or cotton-like texture, while the yeast colonies are cream colored and opaque. All colonies growing on the surface of the membrane should be counted.
The color of the mold colonies will depend on the fungal species present. Common colors include white, green, black, or brown, (but can vary greatly). Yeast colonies tend to be green and opaque. Incubation is for 48 hours at 35 +/- 0.5 oC or up to 7 days at 25-30°C in an aerobic atmosphere.