This is a selective medium for the isolation and enumeration of yeasts and moulds in dairy products. It is in according to a typical formulation of The International Organisation for Standardisation (ISO).
Yeast extract acts as a source of nitrogen, carbon and vitamins in this medium. Glucose is a fermentable carbohydrate. Although the medium has a low pH it is made more selective by the inclusion of chloramphenicol, an antibiotic selective agent.
| Shelf Life (days) | |
|---|---|
| Storage Temp (°C) | |
| Dehydrated Medium Appearance | |
| Prepared Medium Appearance | |
| Dehydrated Medium Colour | |
| Prepared Medium Colour | |
| Dehydrated PH | |
| Prepared PH | |
| Recommended Incubation |
| Organisms | Ref. No | Result |
| Candida albicans | NCPF 3179 | Growth, white colonies |
| Saccharomyces cerevisiae | NCPF 3178 | Growth, white colonies |
| Aspergillus brasiliensis | NCPF 2275 | Growth, white mycelium, black spores |
| Escherichia coli | NCTC 12241 | Inhibited |
| g/L | |
| Yeast extract | 5.0 |
| Glucose | 20.0 |
| Chloramphenicol | 0.1 |
| Agar | 14.9 |
| Total | 40.0 |
| *Adjusted/supplemented as required to meet performance requirements | |
Suspend 40g of the medium in one litre of deionised / purified water. Allow the medium to soak whilst mixing for 10 minutes. Sterilise at 121°C for 15 minutes to completely dissolve the medium. Cool to 42-46°C, mix well and dispense into appropriate sterile containers.