yeast farming

Enlikil · Post by **Enlikil** » Wed Sep 06, 2006 11:25 am

OK, I was reading posts and noticed alot of your have what sounds like your own yeast farms hehe. Can someone explain to me how to Save some yeast and keep it over the years? does this allow you to not buy as much yeast?
Thanks.. i will continue searching.

Uncle Remus · Post by **Uncle Remus** » Wed Sep 06, 2006 11:30 am

I simply scoop some of the dregs (spent grain and yeast) from the fermenter after the wash is done, Put it in a gallon jar, add a bit of sugar and water and put it in the fridge. Next mash I toss it in, I've been keeping it alive for about 10 generations or so now.

KatoFong · Post by **KatoFong** » Wed Sep 06, 2006 11:35 am

If you don't toss sugar into the slurry, can the yeast still live?

Rocky_Creek · Post by **Rocky_Creek** » Wed Sep 06, 2006 11:35 am

At this poin what percent do you think these yeast are capable of producing?

Uncle Remus · Post by **Uncle Remus** » Wed Sep 06, 2006 12:03 pm

I'm sure they would still live without sugar, I'm not talking about adding a lot just a little to keep em happy. I take the jar out of the fridge a few hours before making the mash and let em come alive for a while and then when the mash is ready dump em in. Seems to work for me, all the mashes I've done so far start fermenting quickly (a couple hours).

Rebel_Yell · Post by **Rebel_Yell** » Wed Sep 06, 2006 12:33 pm

Rocky_Creek wrote:At this poin what percent do you think these yeast are capable of producing?

Good question.

Do you think that the yeast is becoming more accustomed to living in a high alcohol environment?

Uncle Remus · Post by **Uncle Remus** » Wed Sep 06, 2006 1:57 pm

When the sugar in a mash is used up I think the yeast just go dormant. Obviously they don't die or I wouldn't have been able to make the last 10 or so grain mashes. The grain left after fermentation is quite sour (acidic, a good enviroment for yeast) they just quit doing there thing because there's no sugar left for 'em to work with. Like I said I store 'em with a little sugar water in a gallon jar in the fridge. Not much happpens in the fridge, but watch 'em come back to life after a couple hours at room temp.

I've never had package yeast (other than turbo) take off as quickly as the cultures I've been saving. So I would say they get stronger from one generation to the next.

BTW I started doing this out of necessity. Brewhaus Canada sucks, they hold the licence to sell Gert Strand products and yet quit carrying whiskey distillers yeast. When I try to buy it from a US supplier, they tell me they can't ship to Canada because Brewhaus.ca is the distributor for Canada.

What a country! .... But anyway if I had of known it was this easy to keep a culture going I wouldn't have given the scumbags my business in the first place.

So there's MHO and rant for today!

Enlikil · Post by **Enlikil** » Wed Sep 06, 2006 4:06 pm

Sweet, NOw whats a good Strain to Pharm LOL hehehe

muckanic · Post by **muckanic** » Wed Sep 06, 2006 6:24 pm

The "store it in the fridge" method is microbiologically crude, but can be effective. However, I would always make up a starter some days in advance using the "1:20" rule, ie, whatever volume you wish to ferment should employ an actively-fermenting starter of 1/20th of that volume, and should be well-oxygenated. The yeast coming out of the fridge will not be actively fermenting, and so it is best to start off a small amount and then step-up the volume once or twice. Another reason for starting small is that yeast stored for a long time could have quite an autolysis stink. Obviously, this all means quite a bit of advance preparation before you brew.

I have heard of yeast being frozen using appropriate additives which stop the cells bursting. A slightly left-field technique is to filter out all nutrients and dead yeast cells, and then store that in H20 at room temperature. The most common technically-sound method, however, is to grow the yeast on the surface of a gelatinised nutrient "slant" and to store that in a screw-top (McCartney) bottle in the fridge.

junkyard dawg · Post by **junkyard dawg** » Wed Sep 06, 2006 8:13 pm

I've made slants and stored cultures before...If I had a yeast strain that I really liked I'd sure do that to keep that strain going. But I don't...

some day maybe...

For now, I've kept a few strains of yeast in the fridge. The only thing I did different was to use a corn mash instead of sugar. When I load the still I save some grain and yeast in a jar, add a little water and put it in the fridge. After the run I do a sourmash and just mix in a little of the new mash into the yeast bottle. Let it warm up for a couple days and it really thrives. The times I have bubbled oxygen from a cutting torch into the yeast have done great, the times I only had sugar did great, they pretty much all worked fine.

I figure you get a couple of months of storage if you just refrigerate your mash, maybe more if you give the yeast a very favorable environment for reproduction.

My whiskey yeast has been going for 20 something batches over about 18 months... so far so good, never had any problems...at least not yeast related problems....

steamed crimped corn....that can be a problem....

Post by **theholymackerel** » Thu Sep 07, 2006 12:01 pm

I was keepin' two different ale yeast strains goin' for quite a while... just to see how it would all work.

I was gatherin' yeast by usin' a sterilised spoon. I'd take it from the peak of the high krausen. Just look for where the clear or white foam is... it'll be the more active spots on the mound that don't have scum on it and are movin' faster.

As long as I kept takin' the yeast from the primary's krausen the yeast stayed very much the same for many ferments, but when I tried the method of "washing" yeast from a yeast bed after the ferment the yeast started to change quickly. When I attempted this with the yeast from a secondary ferment the yeast was VERY different on the very next ferment, and after a few times of doin' this after a secondary ferment the yeast was no longer a true ale yeast... it fermented way too dry and had a strange tart taste.

I imagine with enough patience and generations one could breed an extremely alcohol tolerant yeast.

Rebel_Yell · Post by **Rebel_Yell** » Thu Sep 07, 2006 2:00 pm

What strains have you had good and bad results farming? This might assist us in knowing what to avoid or try.

Thanks for the insight as to you methods theholymackerel.

Can anyone provide links to how to for the slant tube culture methods?

muckanic · Post by **muckanic** » Thu Sep 07, 2006 4:27 pm

="Rebel_Yell". Can anyone provide links to how to for the slant tube culture methods?

I'm too slack to find you links (maybe try the homebrew digest or whatever it is called nowadays), but here's a rough description. First, you need a solution of something that your particular yeast likes to munch on. In the case of beer yeast, that is wort. Next, you need something that will solidify this solution upon cooling, most commonly agar. Boil (or, for the fanatical, autoclave) this stuff, then cool it in a lidded vial that has been propped up to create a sloping surface. A bit of yeast dropped or scraped onto the surface will then grow and start spreading out.

Note that it doesn't necessarily have to be yeast. Bacteria may also be stored by the same method, although they generally grow like wildfire and may require alkaline buffers to counteract the acid production. Ditto for odd-ball yeasts like Brettanomyces. Anerobic microbes provoke further handling issues.

The hardest part is actually ensuring that what you are storing on the slant is a pure strain. This involves a separate process of "streaking" a small solution of yeast across a large solid surface (commonly in a Petri dish) and then picking off what look like individual colonies. A wire loop is typically used for this purpose, flamed to ensure sterility.

Who said you necessarily wanted a pure strain anyway? Good question. The purist approach with multiple strains is to culture each separately. The "store the dregs" approach has the advantage that you keep the lot, but the downside is that some strains may come to be dominated by others, or the yeast may mutate. The usual assumption is that the culture is likely to deteriorate as it evolves and gets contaminated, but it could in principle improve as it adapts to its environment, eg, in a sourmashing scenario.

I have revived yeast from 5-year old bottles of homebrew stored at room temperature. A slightly better method would be to add priming sugar, give the yeast 5 days or so to chew on that and also build up its energy reserves, then store the bottle(s) in the fridge. Unless one is brewing every fortnight or so, I don't particularly like the idea of storing a big jar of sediment in the fridge. What really should be done is taking the dregs from one bottle and starting that up in something like 100 mL (4 fl oz) worth of wort/must. Then build up to 1L (35 fl oz) for a 20L (5 gall) brew.

Enlikil · Post by **Enlikil** » Fri Sep 08, 2006 6:16 am

My wife loves this kinda stuff i'm going to turn her into a yeast farmer to supply my needs hehehe

KatoFong · Post by **KatoFong** » Fri Sep 08, 2006 6:21 am

muckanic wrote:
Unless one is brewing every fortnight or so...

Which is exactly what they should be doing!

Rebel_Yell · Post by **Rebel_Yell** » Fri Sep 08, 2006 5:04 pm

Thanks for the info muckanic.
You provided some great knowledge and insight.

I am some what familuar with Petri dishes, wire loops and autoclaves. It has been 20 plus years since I lit a burner though. I was hoping for someone that knows more to chime in on the how to and hopefully provide links.

Now my thoughts from your post....

How do I get a pure culture? I can buy that. If I take a culture early in my brewing process, I should get reliable results.

Huh, what did I say.... I just bought the latest and greatest yeast strain from Acme Yeast Co. I gots a bottle of their Super Duper Wash Maker pitchable yeast.

Well, I'm gonna be a cheapskate and try to grow this myself. I hate paying their dang shipping costs to BF Egypt.

So what do I do?

Lets get some slant tubes of aguar ready beforehand. I can take my loop and transfer a culture of yeast from my purchased supply to my growing medium. This is as close as I can get to first generation reproduction of my parent yeast.

I am not submitting it to stresses of growing in a super-saturated sugar solution that is lacking nutrients (best way that I know to cause a yeast to mutate).

I am hopefull that you all follow what I am saying.

Can someone help me here?

THANKS!!!!!

muckanic · Post by **muckanic** » Fri Sep 08, 2006 9:49 pm

You're 99% there without any further help. Just remember to rehydrate any dried yeast before taking a loop of it. Also, be aware that streaking the yeast out is designed to give you single colonies, and your commercial yeast could be multi-strain, with some kicking in at different points in the ferment. Nothing to stop you growing up several single colonies and performing a compare and contrast.

I didn't really spell it out, but no yeast goes into my fermenter until it has been started up and passed a sniff test. Dried yeast is just there for emergencies.

zeff · Post by **zeff** » Sat Sep 09, 2006 2:51 am

i seem to rememeber hearing that you cant farm the turbo yeasts.....is this true?

Big J · Post by **Big J** » Sat Sep 09, 2006 4:04 am

Here's another thread on the topic:
http://homedistiller.org/forum/viewtopic.php?t=2126
And a link showing the streaking procedure:
http://www.umsl.edu/~microbes/pdf/streakplates.pdf" onclick="window.open(this.href);return false;" rel="nofollow

-J

hornedrhodent · Post by **hornedrhodent** » Sat Sep 09, 2006 4:54 am

"zeff"]i seem to rememeber hearing that you cant farm the turbo yeasts.....is this true?

That sounds like a challenge to the yeast farmers!

Rebel_Yell · Post by **Rebel_Yell** » Sat Sep 09, 2006 5:31 am

I am not looking to try and find the next great yeast captured from the wild.
I figure that I'll leave that chore to the folks that sell yeast. They should have much more experience than I do.

I have my work cut out just trying to decipher which commercially prepared strain will best suit my uses. LOL

I am wanting to save costs on buying my yeast.

I never considered the multiple strain yeast concoction. Thanks for the heads up muckanic.

I appreciate the links Big J. Now I gots some reading to do.

muckanic · Post by **muckanic** » Sun Sep 10, 2006 10:12 pm

="Rebel_Yell". I am not looking to try and find the next great yeast captured from the wild.
I figure that I'll leave that chore to the folks that sell yeast. They should have much more experience than I do.

As has been indicated previously, it looks like farming a Turbo yeast is not so much the issue as is getting the right nutrient mix. It could be kind of fun, however, to try and breed a champagne yeast that would do 20% ABV from a sugar wash without raunchy by-products. This would involve something like starting with a 14% brew, then creeping the gravity up in successive brews. Actually, the initial problem would be to find a yeast that was happy with just sugar (or possibly glucose) and nutrient. Standard operating procedure would be to use a big yeast starter, keep the gravity under 1060-70 at all times, oxygenate thoroughly every time a sugar addition is made, and add some inert particles to encourage CO2 evolution.

I have had a further think about the best method for storing yeast dregs for long-term use, and it occurs to me that priming a beer bottle is probably not ideal. Instead, it would be preferable to take some yeast at the end of the ferment and to add some wort/must in order to start things off again. Once the sample is actively fermenting, that would be the time to bottle it and get it into the fridge.

muckanic · Post by **muckanic** » Mon Sep 11, 2006 12:38 am

Some links on making slants:

http://hbd.org/brewery/library/yeast-faq.html" onclick="window.open(this.href);return false;" rel="nofollow
http://hbd.org/discus/messages/26895/29 ... 1112623695" onclick="window.open(this.href);return false;" rel="nofollow
http://www.altavista.com/web/results?pg ... reak*+agar" onclick="window.open(this.href);return false;" rel="nofollow

Rebel_Yell · Post by **Rebel_Yell** » Mon Sep 11, 2006 7:56 am

Thanks muckanic!

Great links. I may be dangerous now LOL