Part 2 : Unit 2 : Transferring Agar to Liquid Culture
Now that your spores have germinated and you have live, clean mycelium in a petri dish, it’s time to use this mycelium to inoculate some more substantial food, or substrate. While most mushroom cultivators use colonized agar to directly inoculate grain spawn, we take a slightly different route, which we believe has benefits for first time growers. We will use our colonized agar to inoculate Liquid Culture, in order to grow plenty of “liquid mycelium”. This will allow us to use larger quantities of mycelium when inoculating our grain spawn (in the next step), as well to jump start any future inoculations. In addition, the fact that we use injection ports in our jar lids, means that this extra step doesn’t introduce any additional significant exposure to contamination. Liquid culture can be kept in the fridge for several months and still be viable, so it’s a good storage medium. All in all, Liquid Culture is a tool you should familiarize yourself with in your mushroom cultivation journey. In this chapter, we dive into the Liquid Culture medium and get our hands….well, clean.
The video markers above 👆🏼correspond to the the various Steps in this Unit. Click on them to skip to a Step.
Fill the pressure cooker with about 1.5 inches of water, and then pressure cook the Liquid Culture jar for about 20-25 minutes. Allow the PCAn acronym for Pressure Cooker. to cool down completely before opening it and removing the jars. Once cool, your Liquid Culture jars are ready to be inoculated. Store the Liquid Culture jars in a cool, dry place until you put them to use.
Clean your work environment and SAB. Disinfect the Liquid Culture jar, colonized petri dish, blade wrapper and handle, and anything else you will be using inside the SAB. Remove the aluminium wrapper from the Liquid Culture jar, and remove the parafilm from the petri dish. Disinfect the jar and the dish again, as well as your hands. Spray the air inside the SAB with some fine mist alcohol. Loosen (but don’t open) the LCAn acronym for Liquid Culture – a liquid growth medium for mycelium, usually gown in a jar of sterile nutrient and water. jar lid.
Carefully open up the sterile knife blade and attach it to the handle. Open the colonized petri dish and cut out a healthy and clean looking triangle of mycelium-covered Agar using the sterile blade. Try to lift the triangle with the blade, rather than poking it. Close the petri dish and open the mason jar lid slightly, just enough to allow you to gently drop the Agar triangle into the jar. Then cover the LCAn acronym for Liquid Culture – a liquid growth medium for mycelium, usually gown in a jar of sterile nutrient and water. jar and tighten the lid. Take the aluminium cover you unwrapped earlier from the jar, lightly spray it with alcohol and place it back on top of the jar. Make sure you can see the agar floating in the LC jar, and give it a gentle swirl. You want to avoid any liquid from touching the air filter sticker.
Place the LCAn acronym for Liquid Culture – a liquid growth medium for mycelium, usually gown in a jar of sterile nutrient and water. jar in a dark and quiet place. Temperatures should be between 22-27 °C or 70-80 °F. Mix the liquid in the jar using the magnetic stirrer once a day. If you didn’t use a magnetic stirrer and placed marbles or stones instead, gently swirl the jar to get the stones moving. These will cause the water to stir, and help break up the mycelium inside the jar. After about 7 days to a week, you should see a significant increase in the amount of mycelium inside the jar. Once at least 1/3 of the jar is full of the cloudy mycelium, you can store the Liquid Culture jar in the refrigerator.
Next Unit: Preparing and Inoculating Grain Spawn. Learn how to properly hydrate and sterilize corn kernels as grain spawn. Once sterile, you inoculate the grain with liquid mycelium culture and allow full colonization.
Just a question here
Wouldn’t it be safer to inject a bippsy of the age into the lc through the injection port ?
Like would t theree be a way to suck up some age into the needle and stick it in without opening the jar ?
In theory, that would work. However, the agar is very thick and cant always be biopsied in a way that will hold mycelium in the 18g needle. I would think you would need a much larger needle for this, which at this gauge might cause damage to the injection port.
You can swab some of the mycelium and put it into sterile water, mix/vortex, then inject
That’s a neat trick! Do you sterilize the swabs beforehand, or just get pre-sterile swabs for the job ?
Thank’s so much for all the amazing information & tools; I greatly appreciate it.
Don’t you have to test the Liquid Culture to see if it is contaminated? I heard that you can’t tell unless you put it on agar.
You are correct, you can’t really tell if the liquid culture is contaminated or not, other than obvious signs of discoloration or murkiness. To be certain, you could put a sample of your LC on agar to check for healthy growth, and only then spawn to grain. Saying this, if you stick to the process described here, there’s not much risk of contaminating your liquid culture, especially with the needles and injection ports.