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alive
Psychedelic Farmer



Registered: 08/24/08
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hardened agar
#19333168 - 12/27/13 02:18 PM (10 years, 1 month ago) |
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so i havent done any agar work in a while, but i made up a batch from stamets' dry malt agar mix 3 spoonful for 400 ml...so i cooked it but i waited too long to pour it and it hardend, in the past ive been able to recook, but when i did so this time it never liquidfied...is there something im missing
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Jeff
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Re: hardened agar [Re: alive]
#19333196 - 12/27/13 02:26 PM (10 years, 1 month ago) |
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Re-cooked in a pc? How long? I have done it a few times in the past and never had an issue.
-------------------- Myco-tek
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alive
Psychedelic Farmer



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Re: hardened agar [Re: Jeff]
#19333225 - 12/27/13 02:37 PM (10 years, 1 month ago) |
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ya, in the pc...maybe 20 mins or so
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Jeff
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Re: hardened agar [Re: alive]
#19333240 - 12/27/13 02:42 PM (10 years, 1 month ago) |
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That is odd. I never tried a shorter time than 45 minutes but logic says it should be liquid again in less than that.
-------------------- Myco-tek
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drake89
Mushroom Magnate



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Re: hardened agar [Re: Jeff]
#19333344 - 12/27/13 03:13 PM (10 years, 1 month ago) |
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Quote:
Jeff said:
That is odd. I never tried a shorter time than 45 minutes but logic says it should be liquid again in less than that.
no way. it frustrated the hell out of me cause it took over an hour to melt a couple liters.
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Jeff
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Re: hardened agar [Re: drake89]
#19333364 - 12/27/13 03:20 PM (10 years, 1 month ago) |
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My batches are smaller. 600 ml at the most. Slants are the majority of the things that I have recooked though. I do believe I did a 600 ml flask once quite a while back and don't remember having an issue with it.
-------------------- Myco-tek
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forrest



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Re: hardened agar [Re: Jeff]
#19333390 - 12/27/13 03:27 PM (10 years, 1 month ago) |
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Agar is a gel at room temperature, remaining firm at temperature as high as 65°C. Agar melts at approximately 85°C, a different temperature from that at which it solidifies, 32-40°C. This property is known as hysteresis. Agar is generally resistant to shear forces; however, different agars may have different gel strengths or degrees of stiffness.
from: http://www.sciencebuddies.org/science-fair-projects/project_ideas/MicroBio_Agar.shtml
Melts: 95*C Solidifies: 45*C
from: http://www.funnelbrain.com/c-136885-temperature-does-agar-melt-solidifies.html
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Forrester
aspiring sociopath


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Re: hardened agar [Re: forrest]
#19334983 - 12/27/13 11:35 PM (10 years, 1 month ago) |
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Great info. After my first try at re-melting my extra which had solidified, I thought it just didn't re-liquify, period. Good to know!
-------------------- Repugnant is a creature who would squander the ability to lift an eye to heaven, conscious of his fleeting time here. ------------------- Have some medicinal mushrooms and want to get the most out of them? Try this double extraction method.
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forrest



Registered: 11/16/12
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hmmm i can imagine that something (semi) solid takes longer to heat up than something liquid, but i'm not sure.
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bootster


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Re: hardened agar [Re: forrest]
#19338111 - 12/28/13 06:18 PM (10 years, 1 month ago) |
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I've done it successfully and the agar gets darker but behaves the same as the first run.
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alive
Psychedelic Farmer



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Re: hardened agar [Re: bootster]
#19340246 - 12/29/13 04:22 AM (10 years, 1 month ago) |
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just so all know, the agar heated up just fine, it just needed a little longer...
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Yrat
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Re: hardened agar [Re: alive]
#19355273 - 01/01/14 04:05 PM (10 years, 29 days ago) |
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you can also use a microwave to re-dissolve it more quickly.
-------------------- "There are a thousand hacking at the branches of evil to one who is striking at the root." -Henry David Thoreau Strike The Root
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RandomFX
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Re: hardened agar [Re: Yrat]
#19498277 - 01/30/14 07:42 PM (10 years, 16 hours ago) |
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a newbie stupid question probably, but going to ask it anyways.... If PC'ing sterilizes it, and you can re-melt agar by PC'in it..... Can you just remelt agar that for instance had some contams or after you take a few squares out of it and re-use it? sounds utterly disgusting... but... the stuff isn't cheap at $22 for 250ml.... and does the mycelium really suck a ton of nutrients out of it? usually it seems on top of the puck, and the bottom seems all nice and clear still....
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Jeff
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Re: hardened agar [Re: RandomFX]
#19498352 - 01/30/14 07:58 PM (10 years, 16 hours ago) |
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It's a numbers game. Myself I wouldn't even try. Theoretically though it should work. I would extend the PC time though.
-------------------- Myco-tek
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Mrcloudy
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Re: hardened agar [Re: Jeff]
#19498490 - 01/30/14 08:21 PM (10 years, 15 hours ago) |
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If you leave the contaminant mycelium on the agar when you recook it, it should redissolve the nutrients. Although the nutrients removed would likely be inconsequential I think. I would not risk it myself but give it a try if you want to conserve agar. So long as you are aware of the potential consequences. One must also be wary of toxic spores, one does not want to be inhaling the wrong types of spores. One of the ones I commonly get can cause a pretty bad infection if it grows in the lungs. So if you do try to reuse your agar I would recommend a face mask of some sort. Not worth it in my opinion.
--------------------
10 different Ganoderma species from across the USA AMU MrCloudys guide to North American GanodermaUpdated A rough guide to North American Ganoderma species, with an emphasis on the laccate species.
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Forrester
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Re: hardened agar [Re: RandomFX]
#19499145 - 01/30/14 10:44 PM (10 years, 13 hours ago) |
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Quote:
RandomFX said: a newbie stupid question probably, but going to ask it anyways.... If PC'ing sterilizes it, and you can re-melt agar by PC'in it..... Can you just remelt agar that for instance had some contams or after you take a few squares out of it and re-use it? sounds utterly disgusting... but... the stuff isn't cheap at $22 for 250ml.... and does the mycelium really suck a ton of nutrients out of it? usually it seems on top of the puck, and the bottom seems all nice and clear still....
I've thought of this before as well. This is the kind of thing I WILL try, so I'll let you know. Long as you mark which ones you did with it, I don't see much risk. I'm cheap like that too 
$22 for 250ml? You should really just go with agar agar powder and mix your own with malt extract or whatever other nutrient. Should get a lot more bang for your buck that way 
edit: I just read your other post and think I misunderstood what you bought, so nevermind! Still pretty easy to mix yourself and make different recipes when you want though.
-------------------- Repugnant is a creature who would squander the ability to lift an eye to heaven, conscious of his fleeting time here. ------------------- Have some medicinal mushrooms and want to get the most out of them? Try this double extraction method.
Edited by Forrester (01/30/14 10:52 PM)
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RandomFX
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actually I am pretty sure I have some agar that is contaminated right now, in a pp5, I will just PC the whole darn thing. no need to open it up or anything. then see if anything grows in the next week or so. I suppose to answer my question though I'd have to know how the contam itself developed...does it send live runners, does it grow endospores, and at what stage does it grow them, and how tough are they. I have to admit my biology is weak in this area (And not all that strong in others.) I guess I really do need to change that. The way I see it, is if it is just the growth chains of the contaminant then PC'ing it should kill it probably if it would die within that range, and I think most do, only some tough endospores can survive, well plenty probably can, but they probably are not all that plentiful in our homes. I remember reading their were endospores in AZ like many feet down into the ground and soil, that when awakened could get road crews/etc sick and kill them even from like the dinosaur age or something, but not something that will likely be floating around in my agar.
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