This was originally buried in my current active agar thread and @microbe suggested that I make its own thread instead of burying it and I agreed
I also cleaned it up and used a simpler recipe so as not to confuse newer agar heads. Enjoy.
Original: https://mycotopia.ne...k-some-agar-30/
I've been meaning to write a quick refresher/crash course post on agar in order to make sure all of our newest agar-heads are crystal clear on some basics.
In this thread I'll use a simpler recipe/s. I suggest that one gets some potato flakes and/or malt extract use one or the other as the main nutrition source. Both are suitable for all basic agar tasks (ie spore germination, transfers, storage etc)
- 10g powdered agar (I use telephone brand powder)
- 10g standard nutrition (either potato or ME)
- ~1g "catattives" (trace amounts of future substrates, so if one plans on using popcorn as the grain and straw as the bulk, this would be your "catattives"
- 500ml h2o
- 1-2 drops food coloring for quick identification and differentiation.
Preparation
I take all of the dry ingredients and pulverize the shit out of them in an electric grinder. I want all of the ingredients to be evenly distributed and I want everything to dissolve and/or be suspended in my final jars. I now take the powder and add it to a wide mouth jar (if you're pouring traditional petris, use whatever vessel that'll work).
500ml h2o is added at 212f (100c) so that the agar activates and starts to thicken. Agar is like a rue, or cornstarch, it needs to be boiled to start to set properly. I want this to occur before I start doling it out so that not much sinks. I stir the mixture very thoroughly and then place the jar in a small pot on the stove that I fill with hot water so the jar takes a nice hot bath.
I use a ladle that gives me about a 1/4" of agar in the half pints that I use. It's frugal enough that I'm not wasting it, but deep enough to sustain the mycelial colony if I wait too long to attend to them, or if I have to refrigerate them to delay growth or even to use as masters.
IMHO one shouldn't fill too high if using jars. It'll be hard to see the surface, plus it's wasteful.
Cooking
Stack no pours above the water level/surface with a pie tin placed underneath the insert that came with your PC. If you don't have one, use balled up foil or a towel.
I use unmodified plastic lids (no GE or SHIP), I turn them just barely tight and rarely have a problem with them being too tight or too loose when I retrieve them. If one is stuck, run it under hot water. If you get a really loose lid just discard or tighten the lid and set aside to see if it contaminates.
Bring your PC up to temp with the rocker off. When it starts steaming, set a timer for 10min, that's about how long for one to get a steady stream of steam (that rhymed!) which means the air is purged, which is important for sterilizing properly. Put the rocker on and when it comes to pressure (starts rocking or indicated by a dial), set your timer for 30min, proper sterilization or thermal spore destruction is 30min at temperature and pressure with liquids/agar.
Cooling
Just like pasteurizing, the slower the better!
If you're doing no pours, leave them in the PC with the rocker on, preferably on the burner on which it cooked. No cheating by putting in a cold room/space or taking the rocker off! The slower you cool them the less condensation that you're going to get.
Same thing goes for pouring traditional petri dishes, keep your pouring vessel as hot as you can so that it doesn't harden too much (ie before you're done). Then stack them all so that they stay warmer longer, again lessening condensation.
Spore germination
One only needs a little scrape of spores to go to agar, that's why it's the most efficient use of spores, no waste. If mindful, one can literally start hundreds of 1/2 pint jars or petri dishes from a decent print.
Just drag your scalpel or inoculation needle or inoculation loop/tool across the print. If using a blade, just slice the spores very shallowly into the agar surface. If using a loop or swab, drag the spores in a zig-zag or "S" shape or do your fucking initials.
Making a streak will afford one good places to get good mycelium away from any nasty competitors that may accompany a dirty print or an open air swab.
Having the standard 1:1 ratio leaves the agar moist enough for spore germination (typically).
Transfers
Just like the aforementioned spores, one only wants the tiniest wisp of mycelium to transfer to its new home.
One wants only mushroom mycelium, no extra unseen spores or piggy-backers.
The smaller the piece of myc, the narrower the genetics will be and the closer you'll be to a mono or to a truly isolated set of genetics.
Just swipe with the flat side of your blade right at the tip of the most aggressive growth, then slice into your new agar surface in the center. Same thing goes for an inoculation needle you could employ for this task. If any is going up the glass, grab that! It's aggressive and it's easier to pull a lil piece of myc off the glass surface to boot!
After one does the above techniques, it'll become second nature.
Alright, I hope these tips will help budding agar heads be more successful!
Edited by CatsAndBats, 12 February 2018 - 08:27 PM.
