Growing From Culture
Growing From Culture
**Video Below
Equipment:
- agar/PDA plates
- 10 mL syringes/needles
- honey
- jars
Liquid culture is used to inoculate spawn jars in a very simple and sterile way. Flame your needle, insert into the self-healing port of your mycology lid, and depress the syringe. I tend to use a heavy inoculation ratio; since I usually have this in a 10 mL syringe and it doesn’t keep forever, I might as well use it. I also use quart jars for my spawn, and heavy inoculation not only speeds up colonization but helps the mushroom quickly become the dominant species in the jar, thusly avoiding contamination. It’s also used to extend your culture indefinitely, inoculate agar plates, and ship to buyers.
Mycelia can live in this state for quite some time as long as there are nutrients left in the medium, as long as 3-6 months in some cases. I prefer to use mine quickly, while it’s still fresh. This is one item that’s also very cheap and easy to purchase. I found an eBay seller who gives a 2 for 1 deal, which translates into 20 mL of LC for $15 including shipping. I also purchased from a seller who sent me contaminated culture and refused to make good on the transaction, so caveat emptor. If you’d prefer to make your own, read on.
Procedure | Making Liquid Culture
This procedure assumes you already have your jars of grain prepared and sterilized. Be sure the jars have cooled down enough that the heat won’t kill your mycelia. I generally leave my jars in my canner overnight until ready to use. With this procedure you won’t necessarily need to work inside of your still air box, but I strongly recommend using alcohol or bleach to sterilize everything from your hands to jar lids.
Recipe:
- For a 4% nutrient medium, mix 4 teaspoons of honey into 400 mL of water, preferably distilled or at least filtered. Municipal water can add many contaminants and other problems.
- Cover with mycology lids, finger tight only, and pressure can 30-40 minutes at 15 PSI.
- Let the jars cool, then inoculate, either from other liquid culture or agar plate. You can use a few grains of colonized grain spawn if that’s all you have, but be sure to work within your still air box if you have to open the jars.
- The jars will take several days to colonize. Shake your jars once per day so the mycelia colonizes evenly.
Good vs. bad culture: A good culture is clear. You can see through it. There should be clumps of mycelium floating in it. A bad culture is cloudy and may have a bad smell or green clumps floating on the surface.
Helpful tips:
Do NOT use table sugar for this! Fungi tend to prefer 5 carbon sugars, ie dextrose. Table sugar is sucrose, a combination of two 6 carbon sugars. If you don’t have honey you can use Karo syrup, light malt extract, or corn sugar.
Wait a week or so to see if any cloudiness clears up. Sometimes the mycelia will take care of any problem.
One good way to find out if your culture is contaminated is to inoculate an agar plate or a grain jar. I’m not nuts about this method, especially the grain jar, since it uses up valuable supplies. Pre-poured agar plates are cheap but not THAT cheap.
A glass marble can be added during preparation to assist with stirring.
