Agar

The Preparation

Mix agar and other ingredients and bring to a boil (stove or microwave doesn't matter). Once boiling, pour it into your containers while still hot. If any gets on the mouth or outside of the container wipe off while still warm for easier cleanup and because you don't want anything growing there. When it cools it should harden. This lets you check your work to see if your recipe is working and test its firmness. you want a solid mat that you can easily push your finger through. It will resolidify in the sterilization process later and then harden again when it cools down. any leftover agar can be stored in the refrigerator for later use or "canned" for a shelf stable option. Just heat up later when you are ready for some more.

• The Thick and Thin: You only need to pour enough agar to cover the bottom of the container. However I sometimes pour it quite thick as this allows my cultures to be stored longer. A mix of thick and thin is good so you can make a backup copy of your culture and have one that is easy to cut up and put on grains.
• A Standard Recipe: 10g Agar powder per 500ml water and approx 10g LME or corn sugar.
• My current Recipe:
  • 10g agar Powder
  • 10g corn sugar
  • 2g nutritional yeast flakes
  • 4g ag lime
  • 500ml Water (I substitute some leftover grain water here and makeup the remaining total with plain tap water)
• Food coloring: Not needed but many people use it to differentiate between batches and assist in record keeping.
• Activated Carbon: Or even just very finely ground charcoal can be added to help if trying to clean up a contaminated culture or just because black plated make for pretty white mycelium contrasts.
• Pro-Tip: Use your leftover grain-boil water ("pot liquor") for the liquid—it's packed with starch. Just replace the water in the recipe 1 to 1 ratio. You can also boil it down further to concentrate it, or boil it and jar it for shelf stable later use concentrate using a canning jar or clean recycled used jar with a seal. Using your grain water also helps train the mycelium to eat that starch while on agar before it gets to your grains.

Sterilization Cycles

• Recycled jar lids with a seal need to be vented. Puncture the lid with a tool of your choosing. A nail and hammer, drill etc. Then fill the hole with polyfill, a rag, a cotton ball, cover with "micropore" bandage tape, or for best results use a stick on mushroom filter patch.
• Unmodified Canning Jar Lids Flip lid upside down and tighten the ring to prevent sealing. use lids over and over again.
• unmodified PP Lids Apply lids loosely (tighten, then back off slightly). Let cool completely (overnight is best) before tightening the lid and handling.
• PC/Instant Pot: 45 minutes.
• Oven: 45 minutes at 250°F (121°C).