Media

Media Recipes

Agar

Malt Extract Agar (MEA)

Ingredients:

  • 20 grams of malt extract (light or dark malt extract powder, available at brewing supply stores or online)
  • 20 grams of agar-agar powder (available at health food stores, Asian markets, or online)
  • 1 liter of distilled or deionized water
  • Optional: 2 grams of nutritional yeast or 1 gram of peptone (for additional nutrients)

Instructions:

  1. In a suitable container, such as a flask or a large jar, combine the malt extract, agar-agar powder, and optional nutritional yeast or peptone.
  2. Add the distilled or deionized water to the container and mix well until all the ingredients are dissolved. A magnetic stirrer can be helpful for this step, but it is not necessary.
  3. If you notice any undissolved particles, you can filter the mixture through a coffee filter or cheesecloth.
  4. Pour the agar solution into sterilizable containers, such as glass jars, Erlenmeyer flasks, or petri dishes. If using jars or flasks, fill them about halfway or to a depth of about 1/4 inch (0.6 cm). For petri dishes, pour enough agar to cover the bottom of the dish (approximately 20-25 ml per dish).
  5. Sterilize the agar-filled containers using a pressure cooker or an Instant Pot at 15 psi (121°C or 250°F) for 15-45 minutes, depending on the volume and type of containers. After sterilization, allow the agar to cool and solidify before inoculating with mushroom spores or mycelium.

Potato Dextrose Agar (PDA)

Ingredients:

  • 200 grams of unpeeled potatoes (preferably organic)
  • 20 grams of dextrose or glucose (available at health food stores or online)
  • 20 grams of agar-agar powder (available at health food stores, Asian markets, or online)
  • 1 liter of distilled or deionized water

Instructions:

  1. Clean the potatoes thoroughly to remove any dirt or debris. Chop them into small pieces, with the skin still on, to increase the surface area.
  2. In a pot, add the chopped potatoes and about 1 liter of distilled or deionized water. Bring the water to a boil and let the potatoes simmer for about 30 minutes.
  3. After 30 minutes, carefully strain the liquid from the pot into a clean container, such as a flask or a large jar. This liquid is your potato broth. You may need to filter the broth through a coffee filter or cheesecloth to remove any remaining potato particles.
  4. Measure out 1 liter of the potato broth and return it to the pot or another container suitable for heating. If the volume is less than 1 liter, add more distilled or deionized water to reach the desired amount.
  5. Add the dextrose or glucose and the agar-agar powder to the potato broth, stirring until all the ingredients are dissolved. A magnetic stirrer can be helpful for this step, but it is not necessary.
  6. Pour the agar solution into sterilizable containers, such as glass jars, Erlenmeyer flasks, or petri dishes. If using jars or flasks, fill them about halfway or to a depth of about 1/4 inch (0.6 cm). For petri dishes, pour enough agar to cover the bottom of the dish (approximately 20-25 ml per dish).
  7. Sterilize the agar-filled containers using a pressure cooker or an Instant Pot at 15 psi (121°C or 250°F) for 15-45 minutes, depending on the volume and type of containers. After sterilization, allow the agar to cool and solidify before inoculating with mushroom spores or mycelium.

No-Pour Tek

The “no-pour tek” is a technique to prepare agar plates or dishes without having to pour hot agar into petri dishes. The no-pour tek simplifies the process, reduces the risk of contamination, and is particularly useful for those who do not have access to a laboratory setting or a sterile environment.

The basic idea behind the no-pour tek is to pre-fill containers with agar medium, sterilize them, and then inoculate them with spores or mycelium. Here’s how you can perform the no-pour tek:

  1. Prepare the agar medium: Mix the agar with the appropriate nutrients and water according to the recipe you are using.
  2. Fill the containers: Choose containers with tight-fitting lids, such as small glass jars, plastic containers, or even disposable plastic cups. Pour the agar mixture into the containers, filling them about halfway or to a depth of about 1/4 inch (0.6 cm). Make sure to leave enough headspace for the agar to expand during sterilization.
  3. Seal the containers: Close the containers with their lids. If you’re using glass jars, you can use canning lids or foil to cover the jars. Some people also use breathable micropore tape to cover the openings, which allows gas exchange while keeping contaminants out.
  4. Sterilize the agar: Sterilize the containers and agar using a pressure cooker or an Instant Pot (as discussed in the previous answer). This step is crucial to kill any contaminants present in the containers or the agar mixture.
  5. Allow the agar to cool and solidify: After sterilization, carefully remove the containers from the pressure cooker or Instant Pot and let them cool down. The agar will solidify as it cools.
  6. Inoculate the containers: Once the agar is solid and the containers are at room temperature, you can inoculate them with mushroom spores or mycelium. Work in a clean environment and practice good aseptic techniques to minimize the risk of contamination. Transfer the spores or mycelium onto the surface of the agar using a sterile needle, syringe, or inoculation loop.

Liquid Culture (LC)

Very Good Recipe

Ingredients:

  • 600ml Water
  • 20g (15ml) corn syrup
  • 1g light malt extract
  • 1g peptone

Instructions:

  1. Using 1qt jar, fill with 600ml distilled or deionized water
  2. Add corn syrup, light malt extract, and peptone
  3. Stir to dissolve using spoon or magnetic stir stick
  4. Add stir stick, a piece of glass, or a screw to aid stirring
  5. Cover with lid that includes air exchange and inoculation port
  6. Cover lid with foil to protect filter
  7. Cook at 15psi for 30min
  8. Leave jars in pressure cooker until pressure has equalized and jars have cooled enough to handle

Other Options

Honey Liquid Culture

Ingredients:

  • 1 teaspoon of honey (preferably organic or raw honey)
  • 500 ml of distilled or deionized water

Instructions:

  1. Mix the honey with the distilled or deionized water in a clean container, such as an Erlenmeyer flask or a jar.

  2. Seal the container with a lid and a breathable filter, such as a synthetic filter disc or polyfill.

  3. Sterilize the liquid culture using a pressure cooker at 15 psi (121°C or 250°F) for 15-20 minutes.

  4. Once cooled, inoculate the liquid culture with mushroom spores or mycelium.

Light Malt Extract Liquid Culture:

Ingredients:

  • 10 grams of light malt extract (available at brewing supply stores or online)
  • 500 ml of distilled or deionized water

Instructions:

  1. Mix the malt extract with the distilled or deionized water in a clean container, such as an Erlenmeyer flask or a jar.

  2. Seal the container with a lid and a breathable filter, such as a synthetic filter disc or polyfill.

  3. Sterilize the liquid culture using a pressure cooker at 15 psi (121°C or 250°F) for 15-20 minutes.

  4. Once cooled, inoculate the liquid culture with mushroom spores or mycelium.

Karo Syrup Liquid Culture:

Ingredients:

  • 1 teaspoon of light Karo syrup (corn syrup, available at grocery stores or online)
  • 500 ml of distilled or deionized water

Instructions:

  1. Mix the Karo syrup with the distilled or deionized water in a clean container, such as an Erlenmeyer flask or a jar.
  2. Seal the container with a lid and a breathable filter, such as a synthetic filter disc or polyfill.
  3. Sterilize the liquid culture using a pressure cooker at 15 psi (121°C or 250°F) for 15-20 minutes.
  4. Once cooled, inoculate the liquid culture with mushroom spores or mycelium.