Mix agar and malt

Create a batch for future use (optional)

If you plan to make more agar over time, create a reasonably sized mixture of agar and malt extract. Having a mixture on hand will help keep things simple and organized the next time.

Collect an even amount of Malt Extract and Agar (e.g., 50g each) and mix them in an airtight plastic or glass container. If you leave your MEA mixture out in the open air too long, you'll risk solidifying it due to the humidity in your home. Make sure to shake the mixture well to distribute the contents evenly.

Malt Extract Agar powder mixture

Add ingredients to Erlenmeyer Flask

The target amount of agar and malt extract used for this guide should fill about 10 Petri dishes. Adjust the measurements to your liking if you have more or less on hand.

Weighing the MEA mixture

Mix ingredients with water:

Using a flask, complete the following steps.

1. Add 250 mL of water to the flask.
2. Add 5g of agar and 5g of malt extract to the flask.
3. Stir the mixture thoroughly until there are no clumps in the flask.

Pouring water in flask

Pouring MEA powder in flask

Add Food Dye (optional)

Adding food dye can help create a stronger contrast between the agar and the growing mycelium. The dye's contrast is also helpful if contaminants enter your Petri dish. This guide will use dye, but it is entirely optional.

A few drops of food dye can go a long way, so only add three to five drops.

Adding food dye to flask

Close the opening of the Erlenmeyer Flask

To avoid the mixture boiling out of the flask during sterilization, tightly stuff the opening with nonabsorbent poly-fil.

Flask stuffed with poly-fil

Next, cut a square piece of aluminum foil and cover the poly-fil stuffed opening of the flask. Covering the top with aluminum foil will help prevent water from entering the flask and act as a layer of protection from contamination.

Flask covered with aluminum foil