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ShackNasty · 07-13-2012, 03:41 AM

Quote:

Originally Posted by Saccharomyces

It takes a few attempts to get the right amount dialed in. When I switched agar sources I kept using the same weight, and ended up with slants so thick that yeast wouldn't even grow on them. Oops. Generally the lab agar powder sets up quite a bit firmer than the health food store stuff. Both work just fine.

Thankfully everything seems to be going as planned/described in your thread. I will definitely play around with my agar mixture in the future, as I will absolutely be doing this all the time now. Thank you for the detailed information, you made the whole process much easier. Also, thank you for the response, I appreciate it. It is always nice to hear of first hand experience on different issues.

stillbrewin · 07-19-2012, 03:19 AM

Anyone have a specific pressure cooker they like? I cant seem to get results off amazon that show the psi rating. I am looking for a larger one that I could can wort in. I also want to can some fresh salsa so I am thinking a larger one would be useful say 20 qts aprx. Any thoughts on stainless vs aluminum?

Also If I am making my wort from dme and I boil it first. Is 15 minutes long enough at 15 psi? I am assuming that the total volume of wort needs to reach the desired temp to be sterilized.

On another note I got a really good score off CL. Someone had planned on getting into slanting and changed their mind. I got a 25ml flask, a 125 ml flask, a 2000 ml flask, small stainless funnel, 25ml pipette, package of agar agar, small stir bar, two pyrex petrie dishes, 10 vials (that i dont think I will use they are really tall and thin), an alcohol lamp, inoculating loop, and! a cole-parmer 6x6 stirrer with hot plate for $125.00 whoot!

I already have a 1000 ml flask. I am gonna order some new vials and a couple of racks for them. Should I add in a couple more petrie dishes and possibly a 200 or 250 ml flask?

**cscade** · 07-19-2012, 11:16 AM

I use this pressure canner; it is expensive but will last a lifetime. http://www.amazon.com/gp/product/B0002808Z2/

I can do two layers tall of quart jars in it at one pass. I put the measured water & DME into the jars, close them, and then heat the whole works up to 15psi. I let it run at pressure for 30 minutes, and then cool naturally (don't release the pressure weight). The heat/cool takes a long time on my stove, so the wort is >150F for well over an hour not even counting the 15psi phase.

BoShimTang · 08-06-2012, 03:16 AM

Quote:

Originally Posted by Bru

To me this looks like an alternative to washing yeast and keeping it in 200ml jars but slants take up less space - a typical test tube stand could easily keep ten strains. Are there any other advantages to slanting as opposed to washing ?

Slants can be made utilizing yeast from the smack pack, starter, single colony from a plate, etc... The main advantage is that the yeast has not experienced the strain of being exposed to alcohol. This means the yeast is potentially healthier and has not changed to adapt to a new environment.

FredTheNuke · 08-06-2012, 01:09 PM

This Presto 23qt one works VERY well and is only $80 on amazon:

http://www.amazon.com/Presto-01781-23-Quart-Pressure-Canner/dp/B0000BYCFU/ref=sr_1_2?s=home-garden&ie=UTF8&qid=1344258555&sr=1-2&keywords=pressure+cooker

KaSaBiS · 08-10-2012, 04:07 AM

I love this end of the brewing field. Much appreciation to those posting results of experiments and procedures. I am very process oriented and one thing I need to wrap my head around is cell count by assumptions.

to ask my specific quesiton. How do you approximate cells coming out of your slant before you step up, without using a hemo/microscope. I do not have access to this lab equiptment, but I do understand "close enough" will do just fine. I would have to grow up each slant via many yeast starters do pitch into 10 gal batches. for critical applications, high gravity ales/lager brewing, I am a picky man and want to get a good approximation of how many cells I have.

Do you just assume from a slant to a 250 ml you get X amount, then step accordingly to a 1 L, 2 L and up to a 4 L if for lagers? if so what is "X"

I read about 50 pages on this topic, and understand there is no cut and dry answer. But where do you start before you turn to the pitching calculators?

Larso · 08-11-2012, 01:17 AM

I've inoculated a few slants to start off of 2 different strains. I'm not sure from reading loadsa info on the web. One thing I cant figure out is how should my slants look? Should I have a simple thick white ridge up the slant in a zigzag shape or should I go for a more complete coverage of the medium? Some of mine have covered most of the medium but seem to have loads of very small or thin growth on them while others have this thick raised white zigzag up the middle. I'm guessing that when I cover a large part of the slant surface the colonies dont get the opportunity to grow too much so I end up with more of a thin film? Does this make sense?
What short of coverage should I be aiming for to get the healthiest yeast?

Thanks

L

hopsalot · 08-16-2012, 05:28 PM

The less yeast that is deposited on the slant the more nutrient for the individual yeast cell. Try not to cover the entire yeast with yeast but rather serpentine your loop down the middle of the agar within the slant

Larso · 08-16-2012, 08:57 PM

Thanks hops a lot makes sense

hopsalot · 08-16-2012, 09:24 PM

Quote:

Originally Posted by hopsalot

The less yeast that is deposited on the slant the more nutrient for the individual yeast cell. Try not to cover the entire yeast with yeast but rather serpentine your loop down the middle of the agar within the slant

meant to say "Try not to cover the entire slant with yeast", glad you got the point anyway