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Re-using yeast from last ferment

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OATY1KENOBE

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Guys,

My first batch in my new Fermzilla is about to finish (pressure) fermenting. I have cubes ( same style ) ready & waiting to go , OG 1.037 ( 3.6% Est. ). I've heard that after I do a 'zilla to keg transfer, that I can just tip the next cube straight on top of the old trub and the yeast will re-activate and do the job...…( trub will be cold from cold crash ) I can't be bothered 'washing' the yeast and storing it.

Will this method work ? I'm led to believe that I can get 4-6 batches done this way before the yeast needs to 'retire'.

Mainly I just don't want to have to clean & sanitize the fermenter every time.

Has anyone done this? was it successful ?
 

clickeral

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Have done this in the past in traditional fermenters

Shouldn't be an issue, make sure you add oxygen (by shaking/stirring) so the yeast can do their thing you may end up with slightly more trub if you are not removing any
 

mongey

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I re use yeast all the time ,but I scoop out some into a sanitsed jar and then clean my fermenter and start again

pitching on the old yeast cake is a massive over pitch .I tried it once and the beer was very ordinary.Not sure if it was from the over pitch or dirty fernenter. But would never do it again
 
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philrob

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I'm with mongey and sponge. A whole yeast cake is overpitching, and I also don''t want my new wort onto tired old trub.
I prefer to pitch an appropriate amount of harvested yeast into wort in a clean and sanitised fermenter.
 
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For the time it takes to wash/rinse not worth taking the chance, how long has the yeast been in the fermenter, how much dead yeast is in there? Wash/rinse and collect fresh live yeast. Personally I wouldn't spend 5 or 6 hours brewing then risk losing the batch to bad practice of tipping a fresh wort onto trub.
 
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philrob

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Been harvesting yeast for the last decade.
Generally, I brew again with 1 or 2 days.
Has never been a problem for me.
If you are really worried about it, you can always harvest only a smaller amount (say a test tube) and grow it up on your stirplate (if you have one), so you effectively have fresh yeast.
I guess those commercial brewers who have perpetuated the same yeast for decades (I know they have laboratories etc) must know what they are doing.
 

Chappo666

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Been harvesting yeast for the last decade.
Generally, I brew again with 1 or 2 days.
Has never been a problem for me.
If you are really worried about it, you can always harvest only a smaller amount (say a test tube) and grow it up on your stirplate (if you have one), so you effectively have fresh yeast.
I guess those commercial brewers who have perpetuated the same yeast for decades (I know they have laboratories etc) must know what they are doing.
Ding! Ding! Ding! We have a winner here! 100% Agree...
Only ever had a problem when I was too lazy and or too complacent with hygiene/prep... OR BOTH... anyway don't over think it. Everybody over thinks this shyte. FFS we humans have been brewing for millennia and yet we like to make things 1000 X more difficult for ourselves than they really are in reality. The monks used to inoculate their brews with the same yeast from the same wooden mash paddle, OVER AND OVER AGAIN... I think they might have been on to something.... No? I am sure those monk brew masters weren't masturbating about over pitching the yeast for fark sake ladies and therefore nor should you.

You can always run a crap brew thru the styll wink wink.... Am I allowed to mention the "S" word here? Or do we still have the morality PC police hard at work still? Whoops there's that "S" word again!

Death Is Only An Illusion

Chappo666 OUT
 

MHB

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It depends on exactly what you want to make.
If you are happy with anything that contains alcohol and don't give a crap what it tastes like, its possible that your right.
If you want un-infected beer that tastes great (by modern standards) you might need to take a bit more care.

Chappo, your clearly enthusiastic but a lot of what you have been posting over the last couple of days is very wrong, in this case it isn't even historically accurate, the beer from the days of yore wouldn't be very palatable by todays standards, unless you really are a big fan of wild/sour/lacto beer.

Sure you can reuse yeast, I do, think of a brew as a big starter if you need lots of yeast for a following brew, it comes with a
"But" keep doing it and your beer will end up infected, the beer wont turn out as intended, the yeast will change in ways you aren't expecting.
Brewing rarely rewards laziness
Mark
 

mongey

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Ding! Ding! Ding! We have a winner here! 100% Agree...
Only ever had a problem when I was too lazy and or too complacent with hygiene/prep... OR BOTH... anyway don't over think it. Everybody over thinks this shyte. FFS we humans have been brewing for millennia and yet we like to make things 1000 X more difficult for ourselves than they really are in reality. The monks used to inoculate their brews with the same yeast from the same wooden mash paddle, OVER AND OVER AGAIN... I think they might have been on to something.... No? I am sure those monk brew masters weren't masturbating about over pitching the yeast for fark sake ladies and therefore nor should you.

You can always run a crap brew thru the styll wink wink.... Am I allowed to mention the "S" word here? Or do we still have the morality PC police hard at work still? Whoops there's that "S" word again!

Death Is Only An Illusion

Chappo666 OUT
harvesting yeast and pitching wort onto a used yeast cake in a dirty fermenter are 2 pretty different things
 
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4 days into ferment transferred to secondary, as you can see the yeast left looks fine to use, no hop residue or other break material evident. As its a dried yeast, even though it looks pristine for the sake of $4 or $5 I would much sooner spend that, even if I had another batch ready for a pitch of the same yeast. Different story with a liquid yeast but still limited the number of times I would use.
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Danscraftbeer

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You can get away with this (lazy practice) once, twice, depends how much you may detect the off flavors of dead yeast matter. I have done this lazy practice reluctantly but it is handy in a lazy sense. Also careful technical process The only way is step up in gravity for second brew option. Favoring flavors. In the end it is about best flavors the best way that you can get at a practical value.
Honestly its not that hard to do.
 

MarkosBM

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Hrmm, I don’t agree with the notion that if you pour your wort onto a yeast cake you’re going to get a substandard beer or one riddle with off flavours.

The only time I’ve suffered off flavours in my time is when I’ve pitched old or mishandled yeast. If you’ve got a clean beer with no off flavours then why can’t you repitch directly onto the yeast cake? The only cause for concern to my mind would be any critters that get into the Krausen ring when you open the fermenter up. Other than that crack on.

I did it last week with a cake of M42, with 1051OG pale ale, airlock activity 1 hour after pitch, FG 1008 3 days later.

Beer is crisp, clean and absolutely no off flavours. Throughout my brewing journey I’ve learnt that the brewing process is a lot heartier than most think.
 

gaijin

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Clearly Mark is someone with industry experience and isn't afraid of explaining the scientifically correct and purist ways of brewing. Chappo is clearly very experienced and has been brewing for ages and know what tastes right based on lots of personal experience. I've read both of your posts and learnt heaps from both (including Chappos really old posts). Take a deep breath and keep sharing your thoughts - lots of noobs are probably reading your info due to working from home/social distancing.

Sanitation is the key to re-using yeast. Secondly, be aware that yeast mutate and also become tired, lose vitality and can give autolysis (dead yeast vegemite) flavours. This is especially in subsequent uses of the same yeast cake when it's filled with multiple brews worth of trub and dead yeast. I stopped doing it as I had shitty results on a hefe when I first started brewing. The first batch was awesome. The second was washed out (I didn't know at the time, but you get better hefe flavours from slightly underpitching). The third batch was either infected or mutations had taken hold and was like drinking poolwater filled with bandaids.

TL:DR So, yes you can do it but there are a lot of 'what ifs'. If your sanitation is good and your beers are OG: 1050 or less, repitch once to be safe (unless you're harvesting properly - washing and doing starters) like WEAL and philrob. Use O2 and yeast nutrient to give the repitched yeast a good chance.
 

ABG

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Guys,

My first batch in my new Fermzilla is about to finish (pressure) fermenting. I have cubes ( same style ) ready & waiting to go , OG 1.037 ( 3.6% Est. ). I've heard that after I do a 'zilla to keg transfer, that I can just tip the next cube straight on top of the old trub and the yeast will re-activate and do the job...…( trub will be cold from cold crash ) I can't be bothered 'washing' the yeast and storing it.

Will this method work ? I'm led to believe that I can get 4-6 batches done this way before the yeast needs to 'retire'.

Mainly I just don't want to have to clean & sanitize the fermenter every time.

Has anyone done this? was it successful ?
I've done this a couple of times when I have been super busy with work and didn't have time to harvest and clean like I normally do. Both times the resulting beer was fine.

Dr Hans ran an exbeeriment on his channel and managed to dump his new batch onto the remnants of his last batch for almost a year before running into problems.

Would I recommend it? Nope. Like @MHB says, there are inherent risks with this approach. But as I have seen first hand and watched on Dr Hans Ewechewb channel, you can get away with it for a while. If you have the time, harvest and wash your yeast and sanitise your fermenter. If you don't, take a punt and see how you go.
 

Brads Biabs

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Pitched on yeast cakes more than a few times,
Never struck any problems use the method wisely when doing close to the same or a change up that requires a good kick start.
Sanitation always a key but there's so much over thinking shit in brewing some of its a bit hard to swallow.
 

citizensnips

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For those repitching, the slurry calculator on mr maltys yeast calc has always been a great reference point for how much to re pitch with when at home.

I've used it many times with few adverse effects.
 

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