Recipe: Light Malt Extract Agar (LMEA)

Tips for Success with LMEA

• How to Pour Agar: Whether you're using traditional petri dishes or k-cups, the pouring process should always take place in a sterile environment, such as a Still Air Box or under a laminar flow hood, to minimize the risk of contamination. After sterilizing your containers, slowly pour the agar mixture until it covers about 2/3 of the container's surface. Allow the agar to cool and solidify before moving on to the next step of inoculation or storage.
• Preventing Condensation: After the agar has solidified, store your plates inverted (agar side up) in a cool, dark location. This practice minimizes condensation on the agar surface which could compromise the health of your cultures. To further control humidity, consider adding a desiccant such as silica gel packs to your storage area.
• Storing Agar: Unused agar plates and mixtures can be stored in the refrigerator for later use. Always seal the containers well to prevent moisture loss or contamination. However, do not freeze the agar as this can alter its consistency and negatively impact its performance.
• Storing Light Malt Extract: Light Malt Extract (LME) can be sticky and clump if not kept dry. To maintain its quality, store the LME in a dry place, preferably in an airtight container with desiccant silica gel packs.
• Culture Slants: Culture slants are a great method for longer-term storage of your favorite strains. To create a slant, add a small amount of agar mixture to a test tube and tilt it until the agar coats the sides. Once cooled and solidified, the tube can be inoculated with the desired strain. The culture can be stored for a long time, provided it's kept in a cool, dark place.
• Food Coloring: Add a touch of creativity to your experiments by incorporating food coloring into your agar mix. This doesn't just make your agar plates look more visually appealing, but it can also be a practical way to differentiate between various experiments or strains. However, remember to use food coloring sparingly to avoid inhibiting mycelium growth.
• Check Air Quality: Use your agar plates as a tool for checking air quality. By exposing a plate to the air in your grow area for a short period, you can monitor for any colonies that form, indicating potential airborne contaminants. Regularly testing your workspace in this way is a key part of maintaining a sterile environment for successful mushroom cultivation.