Slanting yeast

Also has anyone actually TRIED sterilizing Baby Soda Bottles (white labs vials basically) in a pressure cooker for 15 minutes? I know their glass temp is 70C and melt temp is 260C but the glass temp is also relative to time. So maybe they won't deform within 15 minutes. If they do I just bought 30 of them for no real good reason... But I ordered 30 Cynmar 24ml glass vials just in case (It was $40.00 for each batch - so worst case I lost $40).

Well my first 28 slants are DONE! The Zurich Lager and German Lager did well. The White Labs Old Bavarian Lager seems to have the uncanny ability to get UNDER the slant and push it up and out of the vial!!!! Out of the 8 slants from this strain 3 pushed up. Out of the other 16 slants from the first 2 strains NONE pushed up. All are nice and healthy white and creamy! Good Stuff! Time to seal and store them!

FredTheNuke said:

Well my first 28 slants are DONE! The Zurich Lager and German Lager did well. The White Labs Old Bavarian Lager seems to have the uncanny ability to get UNDER the slant and push it up and out of the vial!!!! Out of the 8 slants from this strain 3 pushed up. Out of the other 16 slants from the first 2 strains NONE pushed up. All are nice and healthy white and creamy! Good Stuff! Time to seal and store them!

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Fred,

When you fill your vials with agar, try to put in an amount that allows you to leave the vial bottom partially open when the agar is cooling.

If the bottom is not completely covered with agar, the medium will not be pushed up and out by the pressure build up.

Practice with water to find a good fill level.

Jason

Thanks! I slanted at a very heavy angle and only lost 3 out of 24 (ignore the 28 - couldn't count for that post....). But having that bottom open would have improved it. I will cap the 21 good ones tomorrow and fridge them at 36F until ready to be utilized.

I am a high school bio teacher, and i just found a gross (144) of 30 mL glass vials at the back of a supply room when I was looking for something else, probably been there thirty years. Only issue is they are amber. Think that would be alright? It seems like seeing the growth is pretty evident, so I think i'd be able to see through the amber glass.

No problem with amber, in fact it should only do good things. Light is not so important to keeps yeast away from, unlike hops, but UV light is not good for most things. As long as you can see growth through them, which I would bet you can see enough, they are more than fine. Great find.

So I finally tried this over the weekend with White Lab's Essex strain. I had an ESB turn out really good with it, so I want to have this strain available to me year round. Checked the vials today and already at 3 days, I have nice yeast colonies growing. Not sure if I should wait the entire 7 days, as the "Yeast" book indicates you should have decent colonies by 2-3 days, which it appears that I do.

Super exciting to have pulled this off though, it's fun being a yeast rancher.

Hey there,

I hope this message finds you in time. I would fill the bottles to the top with DI (or tap) water prior to sterilization. This would help prevent against deformation of bottle shape.

Best of Luck,

Amazing tutorial!

So to use the slant take it and mix up dme and water into a 2l beaker. Give it about a day and then pour off the extra liquid on top. Pitch the rest into a 5gal batch and that should be enough?

It takes more than a day.... I spend the first 24 hours with the slant culture in a 250ml erlenmeyer. Then transfer to a 1L for 24 hours, then a 2L for 24 hours (all on a stir plate). Then cold crash in fridge for 24 hours, decant and allow to warm up to room temp and pitch. This yields roughly twice the yeast slurry of a store bought White Labs vial starting with a single vial of slanted culture (aka a very small amount of yeast). If you use DME equivalent to your brew you can skip the decanting and if you time it correctly pitch the yeast when fully active - so even less time to activity.

Caylan said:

I'm the owner of the flickr stream cited above.

Here's another link that highlights the yeasty beasties: http://www.flickr.com/search/?w=27291052@N00&q=yeast+culture&m=text

If anyone has any specific questions, let me know.

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Hey those are some great pics! Thanks for sharing. Can you please describe the method you use for streaking plates from bottle conditioned beer as well as from smack packs or other sources?

Thanks,
Bob

Does anyone have the volume measurements needed for the DME and "flaky" agar agar?

@ Polarbeer :

Saccharomyces said:

My recipe for slant media is:

1.5% agar powder
7% DME
1% Wyeast yeast nutrient

That is by weight so if you have, say, 500mL of water you will add 7.5 grams of agar and 35 grams of DME along with 5 grams of the nutrient.

The agar powder def. works better than the stuff I got at the grocery store, which after a few months in the fridge started falling apart.

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This is from page 8 and the same recipe I used with the flaky Agar (by weight)

Also,

Some people following this thread might be interested in the following discussion going on in the feedback section:

Slant Trade/swap subsection

So if you have some cool yeast bank going on with some old/ seasonal/ discontinued or hard to find yeasts, or if you are interested in building upon your existing collection join in

This is from page 8 and the same recipe I used with the flaky Agar (by weight)[/QUOTE]

The problem is I would need the densities of DME and flaky agar to convert to a %volume? Do you remember about how many mL 35g DME and 7.5g agar would be?

Yeah, 500 ml of water

Is Trypticase Soy Broth (TSB) a good medium for culturing yeast? I was given some sterile tubes with this medium in them. Thanks in advance. Oh yah, WOW what a thread. I know I can, I know I can. This is the method for me. No more dry yeast or trying to reuse yeast. Thanks for the education.

One lesson I have learned the hard way lately is this thread mentions that you do NOT need to get your agar/DME solution to a boiling point as you will be pressure cooking it. If you do not get it hot enought, though a lot of the agar falls out of solution as you are filling the vials and you end up with watery slants the next day.... And gelatine on the bottom of the beaker you used to fill the vials. I now get mine up to boiling so the agar stays in solution while filling the vials. Hopefully the 48 slants I made of Wyeast 2001 make it with the watery slants.... They should they just do not look so good...

Sir, your tutorial on slanting yeast was outstanding. In the past I've made several false starts trying this - but using the vials you recommended and the straight-forward procedure for innoculation brought it all within my grasp. I made some nice slants. Now I am wanting to make a starter from one of them, and I plan to purchase a stir plate, but I am confused by your comment about being careful not to drop in the stir bar, to wit:

"Remove the tape from the vial, make sure the lid is tight, and drop the vial in sanitizer before opening. With the sanitized small funnel, add a bit of wort to the vial. Re-cap, shake, and dump into a sanitized 250mL flask. Repeat to get all the yeasties out. Drop in your stir bar (if it isn't already in the flask), and add the remaining wort to the flask."

[SO FAR, SO GOOD....]

"Cover the flask with sanitized aluminum foil and let it ride on the stir plate for 24-36 hours. When it's ready to step up you will know because the wort will look like chocolate milk rather than wort -- that's healthy yeast cells in there!"

[SO FAR, STILL GOOD...]

"Being careful not to drop in the stir bar, decant your small starter into a 1L or 2L flask depending on batch size and gravity. Add enough fresh wort for the volume of starter required. 24 more hours on the stir plate and it will be ready to pitch, or you can refrigerate/decant after 48 hours if you wish. I pitch the whole thing into the fermenter right off of the plate. Typical lag time is about 2-3 hours!"

My confusion is, why don't you want the stir bar in the second flask? Doesn't the stir plate require the bar in the vessel to work? Or is there a different size stir bar required for the larger vessel?

Please explain.
Thanks!!

gkeusch said:

My confusion is, why don't you want the stir bar in the second flask? Doesn't the stir plate require the bar in the vessel to work? Or is there a different size stir bar required for the larger vessel?

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If you drop the stir bar in from the first flask and the stir bar from the second is already in there, you're hosed because two stir bars won't stir. Ask me how I know this.

Thanks for the explanation - I'm sure I would have learned that the hard way.
While I have your attention, do I need to use an erlenmeyer type flask on a stir plate, or will a standard beaker (or even a canning jar) work OK?

I just tried my hand at this for the first time and was pretty impressed with the ease of it. The only thing I am concerned about is after the vials have cooled out of the pressure cooker and I opened up a few today to spread the yeast across a couple vials either let out some gas or sucked some in. I was unable to tell which, but I could hear the noise of air moving. Anyone else experience this? I hope it wasnt sucking in and thus would suck in bacteria or mold.

I've heard that sound also. They are sucking air in because when you put the DME solution in it was close to boiling then you capped them, sterilized them and let them cool off. They cooled to room temperature and the internal pressure reduced below atmospheric. Anyway - I've slanted almost one hundred with this occurring and not yet (knock knock) any issues with bacteria or mold, etc....

When I made mine, i let them cool off completely before sealing up the lid. I used an autoclave, and not a pressure cooker, but it's all the same. I left the lids on, but not completely closed up so you don't get that rush of air in when opening them. If you are careful when you innoculate the slants and have an updraft from a candle, odds of getting something on the slant other than the yeast you are putting on there are pretty slim i'd think.

How does one slant some dry yeast?

milesvdustin said:

How does one slant some dry yeast?

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Ok....I'll ask....why do you want to slant dry yeast? It's already in a form that's ideal for long term storage.

I tried this for the first time today, and everything SEEMED to go as planned, but now I am left to wait and pray for ten days....

I did notice that after letting the agar sit (slanted) for 24 hours it seemed a bit watery. How thick should the agar be? It stayed slanted, for the most part, only a few became unslanted slants. In the future could I add more agar agar to thicken it up? I used agar agar flakes from a local health food store, would it be better to use the agar powder ?

Thanks in advance.

Hi, is there any reason not to re-use old slants? I have some slants that I'm not 100% happy with, i.e. theres yeast growth all over them as I didnt streak them properly and others that I'm just never going to use. Can I just re-autocalve them and start again as surely the autoclave will kill whatever is in them?, might even add to the nutrient value. Could that be done with a mouldy slant also?

Thanks

L

ShackNasty said:

I tried this for the first time today, and everything SEEMED to go as planned, but now I am left to wait and pray for ten days....

I did notice that after letting the agar sit (slanted) for 24 hours it seemed a bit watery. How thick should the agar be? It stayed slanted, for the most part, only a few became unslanted slants. In the future could I add more agar agar to thicken it up? I used agar agar flakes from a local health food store, would it be better to use the agar powder ?

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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.

Saccharomyces said:

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.

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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.

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?

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.

Bru said:

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 ?

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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.

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

http://www.amazon.com/dp/B0000BYCFU/?tag=skimlinks_replacement-20

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?

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

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

Thanks hops a lot makes sense

hopsalot said:

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

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