MALT EXTRACT AGAR
Code: CM0059
A medium for the detection, isolation and enumeration of yeasts and moulds. Bacteria may be suppressed by the addition of lactic acid.
Typical Formula* | gm/litre |
Malt extract | 30.0 |
Mycological peptone | 5.0 |
Agar | 15.0 |
pH 5.4 ± 0.2 | |
* Adjusted as required to meet performance standards
Directions
Suspend 50g in 1 litre of distilled water and boil to dissolve. Sterilise by autoclaving at 115°C for 10 minutes.
If it is desired to adjust the medium to pH 3.5, cool to 55°C and add approximately 2-3ml of 10% Lactic Acid SR0021 to 100ml Malt Extract Agar. Once acidified with lactic acid, the medium should not be re-heated.
Description
This medium, similar to the one described by Galloway & Burgess1 is recommended for the detection, isolation and enumeration of yeasts and moulds. For mycological counts it may be desirable to prepare the more acid medium in order to suppress bacterial growth.
Also see Wort Agar.
Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.
Store the prepared medium at 2-8°C.
Appearance
Dehydrated medium: Straw coloured, free-flowing powder
Prepared medium: Amber coloured gel
Quality control
Positive controls: | Expected result |
Aspergillus niger ATCC® 9642 * | White mycelium, black spores |
| Candida albicans ATCC® 10231 * | Good growth; cream coloured colonies |
Negative control: | |
Uninoculated medium |