Reusing yeast - how many generations?

[wepeeler]

I think the major question at hand would be are we talking about reusing yeast that has already fermented a full batch or are we talking about harvesting yeast from a starter? I would imagine yeast being harvested from a starter and using that to build another starter and harvesting would be reusable for many more than 5 generations, barring any contamination. It's basically fresh unused yeast every time. Makes sense that washed yeast wouldn't be reusable for as long, because it's put in work.

 

[SEndorf]

Good distinction.
I think most of us are talking about fermented yeast, washed and re-used.

 

[wepeeler]

Good distinction.
I think most of us are talking about fermented yeast, washed and re-used.

That's what I'm getting from reading top to bottom. Seems like the discussion keeps going back and forth. Over building a starter seems to be much easier than cleaning and washing, so that's what I'm interested in. I want to push the max and see if I can get 10+ generations out of over building starters. Looks like @MGamber has had some success.

 

[Kiln]

Top crop

 

[jshell55]

Yes actually this happened to me just the other day. I was brewing a stout and a porter at the same time. Similar enough to each other and not finnicky on yeast. I used cheap Nottingham dry yeast in the porter and expensive yeast in the little package where you break the little nutrient sack for the stout.

Sadly the expensive yeast was DOA. Two days after pitching it was not doing squat. The cheap Nottingham was rockin' however. So I did fearlessly transfer some of the live yeast off the top of the porter and it revived my stout no problem.

I believe live yeast off the top could be gathered much better and more consistently than the dormant yeast at the bottom of the primary.

Also clearly you want to use some discretion. The yeast and other sediment in a batch separate out differently and you do want to avoid getting the nasty proteins and leftovers from the cold break. There is a slight color difference which is easy to see. When I harvested it, I poured some of the sediment into a sanitized ball jar with some water, shook it up, and captured the less dense yeast off the top after it settled out.

Sent from my XT1565 using Home Brew mobile app

 

[JAReeves]

Interesting discussion. I have been using a mix of Safale #05 and White Labs #023 since August (6 months). I have brewed a few IPA's, stouts, red rye, blonde, a barley wine (the yeast pooped out on this one at 14% ABV-I added champagne yeast and am hoping for the best), and the yeast seem to be doing fine. I take large sanitized jars (1-2C) of slurry, from the primary only, and let them rest in the back of the fridge (burp them occasionally). If they sit longer than 1 month, I change out the water. I have been getting ~80% attenuation, good beer clarity, and a nice sediment crop at the bottom of the bottle that I can leave behind on a pour with relative success.

To use the yeast, I pour off the liquid, add fresh water, shake vigourously, allow to come to room temp and throw into the fermenter.

I like the taste of the yeast mix, but someday when I don't, or I get a bad batch, then I can start over with my "house culture." I figure that humans have been doing this in a relatively primitive fashion for millennia, and I am just interested to see where the generations of yeast will go with my beer.

Purely for the advancement of human knowledge, mind, the drinking of the experiments is just a necessary evil in the life of an amateur scientist.

 

[Kiln]

Interesting discussion. I have been using a mix of Safale #05 and White Labs #023 since August (6 months). I have brewed a few IPA's, stouts, red rye, blonde, a barley wine (the yeast pooped out on this one at 14% ABV-I added champagne yeast and am hoping for the best), and the yeast seem to be doing fine. I take large sanitized jars (1-2C) of slurry, from the primary only, and let them rest in the back of the fridge (burp them occasionally). If they sit longer than 1 month, I change out the water. I have been getting ~80% attenuation, good beer clarity, and a nice sediment crop at the bottom of the bottle that I can leave behind on a pour with relative success.

To use the yeast, I pour off the liquid, add fresh water, shake vigourously, allow to come to room temp and throw into the fermenter.

I like the taste of the yeast mix, but someday when I don't, or I get a bad batch, then I can start over with my "house culture." I figure that humans have been doing this in a relatively primitive fashion for millennia, and I am just interested to see where the generations of yeast will go with my beer.

Purely for the advancement of human knowledge, mind, the drinking of the experiments is just a necessary evil in the life of an amateur scientist.

I am on #8 of California ale wlp001 for almost a year. Have been top croping with great results. Charlie Papazian author of The Complete Joy of Hombrewing has been using a lager yeast for literally decades. There is a Chop and Brew episode on YouTube that mentions it. So it's for sure infinite if you are thorough approbation and lavish its praise.

 

[Kiln]

This I why I want a good microscope and microbiology degree.

 

[JAReeves]

I am on #8 of California ale wlp001 for almost a year. Have been top croping with great results. Charlie Papazian author of The Complete Joy of Hombrewing has been using a lager yeast for literally decades. There is a Chop and Brew episode on YouTube that mentions it. So it's for sure infinite if you are thorough approbation and lavish its praise.

I will check out chop and brew on YouTube. So many resources! Damn that day job!

 

[SEndorf]

I am on #8 of California ale wlp001 for almost a year. Have been top croping with great results. Charlie Papazian author of The Complete Joy of Hombrewing has been using a lager yeast for literally decades. There is a Chop and Brew episode on YouTube that mentions it. So it's for sure infinite if you are thorough approbation and lavish its praise.

Interesting discussion indeed.
I reuse my yeast but have not gone this far down the road.
My only concern is that most of my beer ends up with friends and family who request duplication of their particular "family favorites."
Doesn't the yeast take on it's own morphed characteristics after this much time?

 

[Kiln]

Interesting discussion indeed.
I reuse my yeast but have not gone this far down the road.
My only concern is that most of my beer ends up with friends and family who request duplication of their particular "family favorites."
Doesn't the yeast take on it's own morphed characteristics after this much time?

Yeah, but it is what some call expressing your terroir.

 

[JAReeves]

Interesting discussion indeed.
I reuse my yeast but have not gone this far down the road.
My only concern is that most of my beer ends up with friends and family who request duplication of their particular "family favorites."
Doesn't the yeast take on it's own morphed characteristics after this much time?

I have read several books that discuss the mutation of the yeast as it goes through generations. I don’t see this as a negative, unless it tastes like a$$ or fails to do its job. It just means you are creating your own “house” strain of yeast, based upon the environmental factors that exist in your brewery. Just like the old school brewers who didn’t have a clue about microscopes or slants, etc.

I am not knocking repeatability, but I do love the mutation that occurs in the natural world when pushed around. I look at it as a conversation I am having with a single-celled organism, a symbiotic relationship that allows for variations in the relationship.

This is not what every brewer wants, of course, so we all find our paths, eh?

 

[JAReeves]

Yeah, but it is what some call expressing your terroir.

This.

 

[SEndorf]

Thank you for your responses.
I think I'll expand my horizons and start with the trusty WLP001 and see what happens with multi-generational harvesting...

 

[BandonBrewingCo]

Zombie resurrection time!

This has been a fascinating read. I like the guy who said "it's not a problem, until it is a problem". So if you're yeast has mutated but tastes fine, then you have nothing to worry about.

For instance, Voss is a bottom cropper so I just harvest it after bottling and store it under beer. I take a teaspoon and add to a starter for the next beer. When my 'original' supply is running low, I'll harvest off a light, clean beer and that becomes my new base to create starters from. Even if that yeast is only good for 6 generations, it'll be good for about 60 batches (10 teaspoons per crop).

However, if I bear in mind that a certain beer will be used as a harvester, I'll put 110% into it to make sure everything is as perfect as possible (no drinking on brewday for example ;-) ). It'll be interesting to see how long my house yeast (Voss) will hold up!