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Asante
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Grain Gel -- a near ideal agar formula substitute
#7496806 - 10/08/07 09:48 AM (16 years, 3 months ago) |
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Agar media can be hard to come by or expensive, and if you make your own you often are faced with the task of gathering unusual ingredients.
No longer!
If you mix a bit of grain flour with water to a paste, and add this to boiling water under good stirring, you are left with a paste that gels or even solidifies when it cools.
It contains all the nutrients of the grain you're using, so if the fungus grows on a particular grain, you can be sure it will grown on the corresponding Grain Gel.
To make GG, grains like rye flour, millet flour and brown rice flour come to mind. You might even grind up WBS to create WBS Gel 
The heat of the boiling water turns the starches into dextrins, which form gels with cool water. When the GG is prepared, you can sterilize and pour it just like regular agar.
Like said: if it will grow on the grain, it will grow on its gel.
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Wronguy

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Re: Grain Gel -- a near ideal agar formula substitute [Re: Asante]
#7496835 - 10/08/07 09:56 AM (16 years, 3 months ago) |
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I have moved this thread from Mushroom Cultivation to this forum so that discussion into the use of this substitute can reach a deeper scale. The idea sounds interesting, but I would like to see some more discussion prior to introducing this to our general cultivating audience.
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Asante
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Wronguy]
#7496842 - 10/08/07 09:58 AM (16 years, 3 months ago) |
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Fine by me
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ThePyschonaut52
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Asante]
#7497041 - 10/08/07 11:08 AM (16 years, 3 months ago) |
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can you write a proper tek? this definetly seems like good idea.
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Asante
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Re: Grain Gel -- a near ideal agar formula substitute [Re: ThePyschonaut52]
#7497169 - 10/08/07 11:46 AM (16 years, 3 months ago) |
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Lets discuss the ins and outs of it first
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theratatat
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Re: Grain Gel -- a near ideal agar formula substitute [Re: ThePyschonaut52]
#7497171 - 10/08/07 11:46 AM (16 years, 3 months ago) |
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This sounds really interesting and easier. A tek would be great!!!!
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ThePyschonaut52
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Re: Grain Gel -- a near ideal agar formula substitute [Re: theratatat]
#7497312 - 10/08/07 12:13 PM (16 years, 3 months ago) |
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well, i guess a problem that exists is the optimal ratio of ingredients needed to achieve a good nutrient/sugars content.
anyone got any clues
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ThePyschonaut52
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Re: Grain Gel -- a near ideal agar formula substitute [Re: ThePyschonaut52]
#7497331 - 10/08/07 12:16 PM (16 years, 3 months ago) |
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im gonna give this a try tomorrow.
-------------------- "In god we trust..." -I guess we're screwed.
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Asante
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Re: Grain Gel -- a near ideal agar formula substitute [Re: ThePyschonaut52]
#7497349 - 10/08/07 12:19 PM (16 years, 3 months ago) |
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Well the nutrients to dextrins ratio obviously is fixed. All that takes some tweaking would be the right flour-to-water ratio to form a gel that is stiff enough.
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ohmatic
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Asante]
#7497502 - 10/08/07 01:00 PM (16 years, 3 months ago) |
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i dont see what would make PDA difficult at all, by every means as simple as it can get.
back when i didnt have a flowhood i could also make and pour my own dishes with close to 0% contam ratio.
i dont understand Quote:
Agar media can be hard to come by or expensive, and if you make your own you often are faced with the task of gathering unusual ingredients.
at all
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Andrew47
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Re: Grain Gel -- a near ideal agar formula substitute [Re: ohmatic]
#7497623 - 10/08/07 01:50 PM (16 years, 3 months ago) |
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Here in wisconsin I can get different rye flours at the store but no agar-agar, I'd have to go searching for it.
I know there is a tek for using brown rice flour as a substitute for agar already
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Andrew47]
#7497698 - 10/08/07 02:22 PM (16 years, 3 months ago) |
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One of the main reasons that agar is used rather than gelatin or just anything that gels is that agar is non-nutritive. It can't be broken down by the organisms that you study. The problem with gelatin is that bacteria and other organisms will break it down and you end up with a watery soup rather than a nice solid plate.
Perhaps that's not so much of a problem with fungi, but once the media breaks down you're not going to have a nice solid that you can use to isolate from. Once it becomes watery any contaminants will pretty much infect the entire plate rather than just the area they happened to land on.
We've had a discussion about using guar gum as an agar substitute before. But that has problems also, mainly that it's harder to work with.
When working with substitutes that aren't non-nutritive and won't maintain gel strength I wonder why not just use standard substrate media instead? What advantages would gelling starch have since it doesn't really have the advantages that agar is usually used for?
You might do just as well making some sort of rice flour jello if you don't care that the gelatin will be degraded over time.
-FF
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Wronguy

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Re: Grain Gel -- a near ideal agar formula substitute [Re: Andrew47]
#7497711 - 10/08/07 02:27 PM (16 years, 3 months ago) |
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I personally see gel strength as the issue here. If the mix proposed does not have the gel strength of traditional agar, mycelia could potentially colonize the entire plate, inside and out.
The goal of agar is to have a 2 dimensional medium in which to observe growth and capture sectors. It seems difficult, if not impossible, to view and capture rhizomorphic sectors when you're working in a 3 dimensional environment. The goal is to have the growth on the surface only, not the entire plate.
Any other thoughts?
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Wronguy

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Re: Grain Gel -- a near ideal agar formula substitute [Re: Wronguy]
#7497717 - 10/08/07 02:29 PM (16 years, 3 months ago) |
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Oops. Looks like I was beaten to the punch. I was typing while you were replying FF.
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lorbitherize
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Re: Grain Gel -- a near ideal agar formula substitute *DELETED* [Re: Asante]
#7499166 - 10/08/07 07:47 PM (16 years, 3 months ago) |
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Post deleted by lorbitherizeReason for deletion: ...
Edited by lorbitherize (10/08/07 07:50 PM)
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Xeluc
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Re: Grain Gel -- a near ideal agar formula substitute [Re: lorbitherize]
#7499676 - 10/08/07 09:57 PM (16 years, 3 months ago) |
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Well guys, I thought I remembered doing this like a year ago and my interest was sparked again by this topic. I did a very quick skim over the available teks on this site and got two mentions of this same idea. So here you guys go 
http://www.shroomery.org/8507/Funkybaloons-no-agar-growth-medium http://www.shroomery.org/8514/Agar-substitute
Btw, the latter seems to be more credible, but I posted both just for the info.
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Asante
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Xeluc]
#7500709 - 10/09/07 07:39 AM (16 years, 3 months ago) |
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Quote:
* 2.5 grams of Brown Rice ground into a fine powder * 8 ml (cc) of water
Excellent, for grains the ratio probably won't be much different from this.
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bonghittr
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Asante]
#7511072 - 10/11/07 10:23 PM (16 years, 3 months ago) |
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I was wondering what about uing the gel as a LC type solution, or for fruiting in the dish? I mean you could use the agar for the isolation use the slurry from the gel to innoc your grains*or whatever you use*
On a side note, I was wondering what kind of things can this be used for when it comes to lab sterile spores, and in a sterile environment. I know there are other thing, but I was looking at it from the aspect that once you isolate on agar and move your wedges to your gel, you can then pick the strongest and most developd rhizomorphic strands to innoc your sub with.
I would rather use a gel than a LC, with the gel i dont think you would face the problem of over wetting the substrate or any of those related issues.
please bear in mind I have been out of mycology for a while, so I have not read up completely on all the new techs and things. I am sorry if this has already been discussed somewhere in detail.
Bong
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odizzle
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Re: Grain Gel -- a near ideal agar formula substitute [Re: bonghittr]
#7511430 - 10/12/07 12:35 AM (16 years, 3 months ago) |
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hey yall well i saw this a my local organics shop a while back and of corse i had to buy http://www.lundberg.com/products/syrup_nf.shtml here's the link to the web site.  I'm not positive but i think it was like 6 bucks ur so. think its usefull!!!
GLUTEN-FREE ALLERGEN-FREE WHEAT-FREE they cook brown rice in pure filtered water then evaporate the water .Whats left is "golden syrup" Whole grain goodness Anybody seen or used this before??
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Edited by odizzle (10/12/07 12:36 AM)
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: odizzle]
#7511545 - 10/12/07 02:08 AM (16 years, 3 months ago) |
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Hey everybody, I was reading the first few lines of the thread, and I havn't read all the posts yet, but I would just like to tell you that agar agar is not hard to find, and it is extremely cheap if you know where to look.
Go to one of those little oriental grocery stores, and ask them for agar agar. They'll sell it to you real cheap.
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: odizzle]
#7511548 - 10/12/07 02:11 AM (16 years, 3 months ago) |
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Quote:
hey yall well i saw this a my local organics shop a while back and of corse i had to buy http://www.lundberg.com/products/syrup_nf.shtml here's the link to the web site.
I'm not positive but i think it was like 6 bucks ur so. think its usefull!!!
GLUTEN-FREE ALLERGEN-FREE WHEAT-FREE they cook brown rice in pure filtered water then evaporate the water .Whats left is "golden syrup" Whole grain goodness Anybody seen or used this before??
Yes, I have a jar of it less than 10 feet away from me. It's very tasty and has a very mild pleasant taste with a nice depth to it. It goes great in miso tahini spread. They sell it at pcc in seattle and many other health food stores I'm sure. But like I said you don't need to buy this. Go to the little oriental store. You'll be amazed what you find there. Take a look around, and you will very likely make it one of your regular shopping locations.
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: a_guy_named_ai]
#7514115 - 10/13/07 11:29 PM (16 years, 3 months ago) |
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Quote:
jonathan_206 said: ...I would just like to tell you that agar agar is not hard to find, and it is extremely cheap if you know where to look.
No, agar isn't cheap. Hence the search for substitutes. Agar is about $50 per pound.
-FF
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7514801 - 10/14/07 05:57 AM (16 years, 3 months ago) |
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Fine, don't believe me.
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: a_guy_named_ai]
#7515487 - 10/14/07 11:48 AM (16 years, 3 months ago) |
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The little store I went to sold little packages of agar in I'm guessing 1 oz. packages for somewhere around a dollar. 16 dollars a pound would be cheap wouldn't it? Even if I'm slightly off than what I'm guessing, i don't think it would be a whole lot more expensive. From what I recall it weighed the same about as the agar agar package here by eden foods.
http://www.edenfoods.com/store/product_info.php?products_id=108940
It's just that people charge huge mark up for "rare" products (products that white people have a hard time finding). If you go to a health food store they'll charge you like 6 or 7 dollars for something you can get in chinatown for dirt cheap.Whoever sells you a pound for 50 dollars is ripping you off.
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Andrew47
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Re: Grain Gel -- a near ideal agar formula substitute [Re: a_guy_named_ai]
#7516029 - 10/14/07 02:33 PM (16 years, 3 months ago) |
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jonathan,
You are talking about agar agar. Not nutrient agar. Lets say you make PDA, so 20 some bucks for agar and potatoes + how many hours it takes of time to make it
Paul stamets' company sells his 'enhanced' nutrient agar for 35 dollars a pound in comparison. Still not cheap
Let's drop the squabbles and try out these new recipies
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Andrew47]
#7517378 - 10/14/07 08:32 PM (16 years, 3 months ago) |
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Jonathan, the link you posted is for oz packets @ $5.84. That works out to 93.44 per pound.
If you really think that you can get agar for $6-7 in chinatown then buy it up and sell it off at the going rate of around $50/lb.
> Whoever sells you a pound for 50 dollars is ripping you off.
No that's just the going rate. I should also point out that that's the price for food grade agar, which generally isn't even used in science.
Andrew, you point out that nutrient agar is cheaper than agar. This is because the expensive agar is "cut" with the nutrients needed to make a suitable media. That makes it cheaper than straight agar.
If anyone would like to post sources for agar at less than $50/lb. I'm sure that people here would be happy to hear of them.
-FF
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Hotnuts
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7518669 - 10/15/07 08:31 AM (16 years, 3 months ago) |
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Anyone with a computer can obtain agar. I use this stuff. It sells at a good price as well.
Agar Powder
Edited by Hotnuts (10/15/07 08:32 AM)
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Hotnuts]
#7519767 - 10/15/07 02:41 PM (16 years, 3 months ago) |
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Quote:
Jonathan, the link you posted is for oz packets @ $5.84. That works out to 93.44 per pound.
If you really think that you can get agar for $6-7 in chinatown then buy it up and sell it off at the going rate of around $50/lb.
Fred, I wasn't talking about that agar I linked to. I was using that as a comparison. The agar I'm talking about is the same kind but it only costs a dollar a packet.
Quote:
If anyone would like to post sources for agar at less than $50/lb. I'm sure that people here would be happy to hear of them.
I already told you you're just in disbelief. 16$ about I'm guessing for a pound of basic agar. I have to go to the hardware store which is close to the shop so I'll check out the exact price and get back to you. It's going to be very difficult to find these kind of prices on the internet. If this was on the internet, the prices would go up. These people at the oriental stores don't realize the need for it in growing mushrooms apparently. They use it for making jelly deserts.
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: a_guy_named_ai]
#7519977 - 10/15/07 03:31 PM (16 years, 3 months ago) |
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Quote:
Hotnuts said: Anyone with a computer can obtain agar. I use this stuff. It sells at a good price as well.
Agar Powder
That link points to a source selling agar for $46.56/lb, which is pretty much what I've been telling people the going rate is.
> 16$ about I'm guessing for a pound of basic agar.
Then buy it up and become a vendor. Apparently you're such a good shopper that you can find things at a fraction of the cost of the going rate.
> If this was on the internet, the prices would go up.
Umm... It usually works quite the opposite way. Agar is not cheap to produce. People are not jacking up the price because they know it's used in mycology.
Whatever agar you get at a fraction of the going rate is going to be of the lowest quality available and will probably be cut with waste seaweed extract that increases the weight without adding any gelling strength.
If you can find agar that will gel at 1.5% concentration for anywhere near $16/lb then let us know. I'll buy about 5 pounds from you.
I'm guessing that your cheap oriental agar is not going to gel at normal concentrations, therefore making it no bargain at all.
-FF
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Hotnuts
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7520245 - 10/15/07 05:04 PM (16 years, 3 months ago) |
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I have seen rather large bags of agar flakes at a Korean store for pretty cheap. I don't know about them being that cheap though. The going rate for agar powder is in the 45-50 dollar a pound range. A few ounces of agar powder goes quite a ways though.
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a_guy_named_ai
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7520873 - 10/15/07 08:16 PM (16 years, 3 months ago) |
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well I just got back from shopping. I went to the store and it was very close to what I mentioned before. 25 grams (0.88 oz.) for 99 cents.
I don't know what you're talking about fred the agar being cut it sounds like you're saying. I've never seen agar say it has anything else than agar. I have no idea. I'm not trying to be a know it all, I don't know much really. I was just trying to help people out. I think you should go check it out.
later
Edited by jonathan_206 (10/15/07 08:24 PM)
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MotorCityMadman
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Re: Grain Gel -- a near ideal agar formula substitute [Re: Asante]
#7547046 - 10/22/07 02:04 PM (16 years, 3 months ago) |
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I'm no authority, but PDA is better because it is selective to fungi. Your grain stuff is going to contain a lot more nutrient compounds than PDA and thus be more hospitable to bacteria.
Since most of us are not trying to produce shrooms on an industrial scale, the cost of agar agar is not prohibitive, and imho is worth the expense.
I buy agar agar flakes for about $5 and this produces several litres of medium...80% of which goes promptly down the drain since I never need much.
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: MotorCityMadman]
#7547318 - 10/22/07 03:13 PM (16 years, 3 months ago) |
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> I'm no authority, but PDA is better because it is selective to fungi.
You got the first part right, just not the second part.
> 80% of which goes promptly down the drain
You might want to watch that, lest your agar gel up in your sink trap. It's kind of like pouring grease down the drain, don't do it.
I'm not sure why you would make more media than you need just to waste it anyways.
-FF
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RogerRabbit
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7547370 - 10/22/07 03:26 PM (16 years, 3 months ago) |
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Quote:
I went to the store and it was very close to what I mentioned before. 25 grams (0.88 oz.) for 99 cents.
This was 7 dollars for an ounce, as can be seen. This is what you want. If you can find a better price, great. I run it through the coffee grinder to make it powder before mixing with the malt and yeast. I recommend MEA. If bacteria is a problem, gentmycin sulphate is autoclavable. RR
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Andrew47
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Re: Grain Gel -- a near ideal agar formula substitute [Re: RogerRabbit]
#7547379 - 10/22/07 03:28 PM (16 years, 3 months ago) |
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So has anyone tried using the grain gel yet?
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MotorCityMadman
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Re: Grain Gel -- a near ideal agar formula substitute [Re: fastfred]
#7550375 - 10/23/07 10:54 AM (16 years, 3 months ago) |
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Quote:
fastfred said: > I'm no authority, but PDA is better because it is selective to fungi.
You got the first part right, just not the second part.
> 80% of which goes promptly down the drain
You might want to watch that, lest your agar gel up in your sink trap. It's kind of like pouring grease down the drain, don't do it.
I'm not sure why you would make more media than you need just to waste it anyways.
-FF
OK, expert: http://en.wikipedia.org/wiki/Potato_dextrose_agar
I make more than I need because usually I only need about 4 dishes worth. It's easier to measure the ingredients to make .5 litres than it is to measure for .05 litres--the error is less significant with the larger quantity.
Besides, I shit money. So there.
And I don't pout hot agar down the drain. Give me some credit. Sheesh.
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fastfred
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Re: Grain Gel -- a near ideal agar formula substitute [Re: MotorCityMadman]
#7559247 - 10/25/07 01:29 PM (16 years, 3 months ago) |
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Looking around I was able to find some pretty cheap sources. I'm betting that the quality is pretty low. Probably lower gel strength and contaminated with nutrients and salt, but that really shouldn't be too much of a problem.
http://www.harvesthealth.com/nowagpo2o.html http://www.asianfoodgrocer.com/index.asp?PageAction=VIEWPROD&ProdID=507
Previous searches had only turned up larger quantities in the $50/lb range. That's still the only bulk price I can find around my location and on the internet. The small packages at my local co-op are all flavored gelatin substitute mixes and the bulk is around $60/lb. Kind of strange that these asian stores can sell small quantities so far below the going rate. I wonder what's up with that?
Quote:
MotorCityMadman said: OK, expert: http://en.wikipedia.org/wiki/Potato_dextrose_agar
Wikipedia is wrong. The citation attached to the comment that PDA is not usually used to grow bacteria actually says the opposite.
Anyone who's left a PDA dish open for a couple minutes knows that plenty of bacteria grow well on it. It's not selective against bacteria whatsoever.
There is a common practice of using it for molds and fungi because they grow so well on it, but it's just as common in bacteriological labs. There is also a practice of sometimes adding tartaric acid to lower the pH to around 3.5. A pH that low disfavors bacteria, but that's not standard PDA, which has a pH of 5.6.
-FF
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