Continuous Yeast Use

[ChrisECarpenter]

So, my brewing project has gone from the occasional keg filler to putting a 60L fermenter down each week.
This is partially due to consumption, partially due to going from ales to a pilsner which I want to give plenty of time to lager and cold condition.

My plan is to rack from the primary once the ferment has done most of its work, and take the bulk of the beer off the yeast cake into a secondary container for the lagering and cold conditioning.

If I then fill the original fermenter with warm wort (20 degrees or so) and mix the yeast cake back in, I assume the yeast will kick off again and do a good job.

The yeast in question is Saflager S34/70.

Will I eventually 'wear out' this yeast? Id prefer to not keep chucking in dry yeast packs at $11/bag and I figure this is the best way to keep costs down and maintain a healthy yeast population.

Thanks - Chris.

 

[amiddler]

You probably wont need that much yeast each time and would want to "thin" it out by removing some each time or remove enough for the next brew then wash, sanitize fermenter before adding the yeast back. I've heard but not proven myself that 5-6 times re-use is about as far as your should push a yeast before it starts to mutate. Still 1 yeast, 5 brews is pretty good.
Drew

 

[Sunshine_Brewer]

Yeah don't use all that yeast at once, check out wolfys post's on yeast washing or look at this website mrmalty.com and check out his version of yeast washing/pitching.

You can get off flavours or bad haze or both using a whole yeast cake, don't do it. It aint necessary.

 

[Nick JD]

When you're bottling/kegging, leave about 300ml of beer in the bottom of the fermenter.

Swirl the fermenter gently round and round so that (depends on yeast, but most do this) the 300ml of beer slowly gets cloudier an cloudier, but isn't picking up chunks of trub. You want it to be picking up the freshest yeast at the top of the trub.

Then take a 300ml PET bottle that's super sanitized and fill it with the mucky soup. Write the yeast type and the date on it.

I try to get (for a single batch) around 15mm of healthy yeast in the bottom of the bottle - when settled out. I've found more than this is a bit of an overpitch, less is under.

I'd take 600ml for a double batch.

 

[sama]

Rinsing the remains is the go mate.wolfy did a post here recently but theres plenty on the subject out there online.for ales,i rinse,obtain 15 to 20ml of clean yeast and then grow it in a 1500ml starter for 24hrs.

 

[Mikedub]

and its an enjoyable process while making you at one with the yeast



Go forth my beauties, multiply and convert!

 

[QldKev]

So, my brewing project has gone from the occasional keg filler to putting a 60L fermenter down each week.
This is partially due to consumption, partially due to going from ales to a pilsner which I want to give plenty of time to lager and cold condition.

My plan is to rack from the primary once the ferment has done most of its work, and take the bulk of the beer off the yeast cake into a secondary container for the lagering and cold conditioning.

If I then fill the original fermenter with warm wort (20 degrees or so) and mix the yeast cake back in, I assume the yeast will kick off again and do a good job.

The yeast in question is Saflager S34/70.

Will I eventually 'wear out' this yeast? Id prefer to not keep chucking in dry yeast packs at $11/bag and I figure this is the best way to keep costs down and maintain a healthy yeast population.

Thanks - Chris.

There's been discussion about mutating yeasts, and I beleive it doesn't. I can't recall the names of the breweries, but there are breweries that reuse the same yeast for years. They have been mentioned on here a few times.

My current S-189 yeast cake is just over 3 months old, with it constantly brewing. This yeast was already used by ekul and it was a 330ml bottle from his brew.
My current W34/70 cake is about 2 months old, with it constantly brewing.

I only ever swap out the yeast cake when I want a new strain in action.

Washing the yeast etc is probably the best way, but personally I can't be bothered. Check out mrmalty to work out how much yeast you should be using for the strain. I just swirl the dregs in the fermentor around, if you want to keep it pour it into 330ml bottles and cap them / or if you don't want it just dump it, leaving about a good cup full in the fermentor. Throw on your next cube of beer and of it goes. Always taste the beer coming out before reusing the yeast, and any sign of an infection just dump the yeast.


QldKev

 

[Yob]

There's been discussion about mutating yeasts, and I beleive it doesn't. I can't recall the names of the breweries,

when I visited the Fransiscan Well Brewery in Ireland he had a yeast that was 128 brews old :blink:

Yob

 

[ekul]

My current S-189 yeast cake is just over 3 months old, with it constantly brewing. This yeast was already used by ekul and it was a 330ml bottle from his brew.

Is it that old already!? I'm still using the same one, it had gone a few generations before i gave it to you. AS soon as i empty the lager fermenter i drain most of the yeast out and then throw another cube on top.

I've thought about washing yeast too, but i'm paranoid of infection so i don't like touching the yeast too much. If the previous beer tastes alright, i figure that the yeast is still healthy and uninfected.

 

[AndrewQLD]

There's been discussion about mutating yeasts, and I beleive it doesn't. I can't recall the names of the breweries, but there are breweries that reuse the same yeast for years. They have been mentioned on here a few times.

My current S-189 yeast cake is just over 3 months old, with it constantly brewing. This yeast was already used by ekul and it was a 330ml bottle from his brew.
My current W34/70 cake is about 2 months old, with it constantly brewing.

I only ever swap out the yeast cake when I want a new strain in action.

Washing the yeast etc is probably the best way, but personally I can't be bothered. Check out mrmalty to work out how much yeast you should be using for the strain. I just swirl the dregs in the fermentor around, if you want to keep it pour it into 330ml bottles and cap them / or if you don't want it just dump it, leaving about a good cup full in the fermentor. Throw on your next cube of beer and of it goes. Always taste the beer coming out before reusing the yeast, and any sign of an infection just dump the yeast.


QldKev

Hey Kev, the problem with reusing yeast too much is that if there are subtle changes with the yeast be it "mutating" or slight infections the changes can be so slow and slight that often a brewer will not pick up the faults in their beer at all, but if you brewed a side by side with a generations old yeast and a fresh sample I think you will be pretty surprised the difference in taste.
I think you'll find that the breweries you mentioned above don't just take a scoop of the yeast from the previous brew and use it in the next one, it's more likely that they are propagating a very old strain on a regular basis using sterile propagation techniques so they are basically using a fresh culture of the original yeast each time they brew.
However I am happy to be proven wrong.

Cheers
Andrew


Andrew

 

[Bribie G]

IIRC even Carlton (Fosters) send off to Denmark for their yeast from time to time. Couldn't have that metallic twang mutating into something more drinkable

 

[Greg.L]

It's not possible to do a ferment without getting contamination, both wild yeasts and bacteria. Yeast/bacteria spores are ubiquitous in the environment and every time you open your fermenter you get contamination. That's not to say you can't re-use yeast, but you will be using a mixed population, it isn't possible in a domestic situation to keep a pure culture. Breweries use microbiologists to maintain their yeasts, and have laboratories built for the purpose.

Re-using yeasts will definitely increase your chances of getting an infection, though beer brewing is such a safe easy process you should be ok.

 

[BOG]

There's been discussion about mutating yeasts, and I beleive it doesn't. I can't recall the names of the breweries, but there are breweries that reuse the same yeast for years. They have been mentioned on here a few times.

My current S-189 yeast cake is just over 3 months old, with it constantly brewing. This yeast was already used by ekul and it was a 330ml bottle from his brew.
My current W34/70 cake is about 2 months old, with it constantly brewing.

I only ever swap out the yeast cake when I want a new strain in action.

Washing the yeast etc is probably the best way, but personally I can't be bothered. Check out mrmalty to work out how much yeast you should be using for the strain. I just swirl the dregs in the fermentor around, if you want to keep it pour it into 330ml bottles and cap them / or if you don't want it just dump it, leaving about a good cup full in the fermentor. Throw on your next cube of beer and of it goes. Always taste the beer coming out before reusing the yeast, and any sign of an infection just dump the yeast.


QldKev

Do you wash out the fermentor and remove the Krausen crudd stuck to the side etc, or just pitch the cube back into the fermentor unwashed?


BOG

 

[ekul]

Do you wash out the fermentor and remove the Krausen crudd stuck to the side etc, or just pitch the cube back into the fermentor unwashed?


BOG

I'm pretty sure Kev does exactly what i do... Remove some yeast and then throw another cube on top without washing anything.

I feel that the layer of krausen stuck all over my fermenters actually form some kind of protective layer, in reality it probably doesn't though. Seems to work, i've been doing this with the same yeast for apparently four months now ithout infection.

 

[QldKev]

Do you wash out the fermentor and remove the Krausen crudd stuck to the side etc, or just pitch the cube back into the fermentor unwashed?


BOG

I'm pretty sure Kev does exactly what i do... Remove some yeast and then throw another cube on top without washing anything.

I feel that the layer of krausen stuck all over my fermenters actually form some kind of protective layer, in reality it probably doesn't though. Seems to work, i've been doing this with the same yeast for apparently four months now ithout infection.

ekul's got it in one.

It's bit bit like a tree and how you can count how many rings is how many years old it is; just in this case it's how many brews. :unsure:

QldKev

 

[QldKev]

Hey Kev, the problem with reusing yeast too much is that if there are subtle changes with the yeast be it "mutating" or slight infections the changes can be so slow and slight that often a brewer will not pick up the faults in their beer at all, but if you brewed a side by side with a generations old yeast and a fresh sample I think you will be pretty surprised the difference in taste.
I think you'll find that the breweries you mentioned above don't just take a scoop of the yeast from the previous brew and use it in the next one, it's more likely that they are propagating a very old strain on a regular basis using sterile propagation techniques so they are basically using a fresh culture of the original yeast each time they brew.
However I am happy to be proven wrong.

Cheers
Andrew


Andrew

Faults in my beer, never! Be a good test to try and ferment 2 beers side by side, old yeasties and a fresh pack. The mutation, if exists, could be getting used to my brewing environment and make better beer, who knows.

QldKev

 

[leonjw]

I'm glad this thread popped up... I was deciding if I should/shouldn't pitch onto the cake for the third time.
It looks like the next batch will be going right on in there after draining some of the old cake out.
I didn't remove any of the yeast from the first batch before I added the second.

 

[sama]

I'm pretty sure Kev does exactly what i do... Remove some yeast and then throw another cube on top without washing anything.

im shocked!!!! i just.....just couldnt do it (sanitizes hands after typing)

 

[QldKev]

im shocked!!!! i just.....just couldnt do it (sanitizes hands after typing)

Sanatise hands before typing, otherwise it will end up in a keyboard infection which will carry through out the house and end up in the brew.

QldKev

 

[leonjw]

im shocked!!!! i just.....just couldnt do it (sanitizes hands after typing)

lol reminds me of this scene from black books:



albeit a bit off topic...