Yeast recycling

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Hi folks i am quite new to brewing my own beer and i recently watched some videos on you tube showing folk going through quite a few processes and gathering up the yeast that they had previously used in past brews. Is there any advantage to doing this apart from the cost ? Yeast is pretty cheap to buy anyway and it looked like an awful lot of work and time involved just to save a little bit of cash.
 
Some people do it all the time, others never bother with it. I tend to the latter camp. I've made one or two attempts, but the results haven't encouraged me to persist. However, clearly many experienced brewers get very good resulta doing it.

What I would say is, get some experience under your belt with 'fresh' yeast at first, then decide if you want to go down that path.
 
My wife uses fresh trub to bake bread. Straight out the FV after terminal FG into a big clean jug add sugar and leave in a warm place covered with cling film. Once bubbling This goes in the bread flour. It is usually brilliant! (CML Ale yeast.)
 
I've reused yeast many times (Craig was the first guy I saw do it when he first started on YouTube) and not once had a negative issue.
● I've pitched a fresh batch straight on top of a yeast cake.
● Collected part of the yeast cake and stored in several 500ml pet bottles in the fridge, sometimes for months until I'm ready for a batch, bring it to room temperature and throw one in.

The latter has sometimes taken a day or so to start up, but always has, and after reading so much about the reuse of yeast I've surmised that washing it is not necessary, at least not at my level of homebrewing.

This year I decided to go one step further and build up a yeast bank in my fridge just because I can, and because I bought relatively expensive dried yeasts I've not tried before and wanted to keep a few samples to make starters with next time out.
IMG-20220922-WA0000.jpg

I originally just kept EC-1118 for my ciders when I started if I'm honest, because it is such a beast and I didn't want to keep paying £3 for a 4.5g pack. Now years on and reading hours and hours of information on storage, cultivation etc, I realise you can reuse pretty much any yeast if you follow good sanitary practice.

That's what I'm doing and I love it..... feel like Quincy 🤣
 
Many years ago, I used to re-use yeast. Sometimes it would be chucking fresh wort onto a yeastcake of a previous brew (I would scoop out about 75% of the yeast cake with a sanitised spoon to prevent over-pitching). Normally this would be if the next batch was going onto the yeastcake within 24 hours of the previous batch being racked off.

If it was over 24 hours between racking and the next yeast pitch, I would scoop out the top layer of the yeast cake/slurry into a sanitised (or sometimes sterilized if my wife had been jam-making) jam jar. I would then just stick that in the fridge. I wouldn't keep this for more than 6 weeks and it was always good, but I could keep this going for many generations (though I tended to not go over about 4-6 gens).

I did this mostly because it was fun to do, saved me a little bit of money and also time/effort as I used to go to local breweries and they would gift me some of their yeast.
Nowadays, I go for the easy option. I don't re-use yeast (also there is less room in the fridge to store it). For the price of £3 per batch in easy-to-store, easy-to-use dried yeast it's far easier for me to use every time. I don't have to muck about with starters, and I don't have the fear of an infected batch.
 
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Yeast is pretty cheap to buy anyway and it looked like an awful lot of work and time involved just to save a little bit of cash.

No it isn't, some lagers require multiple packs of not too cheap yeast.
To get your head around it, just rack your new wort on the yeast cake(less cleaning), i have 3rd generation ready this way, awaiting for kegging. It makes your brewday longer, as you need to keg it whilst brewing, but on the long term it pays itself.
 
Over the half century that I have been brewing I estimate that most of my failures with "off" batches have been down to re-using yeast. I now use a fresh sachet of dried yeast for every brew. I keep the cost down by buying 500g packs and re-packaging the yeast in 12g lots using 10 x 15cm vacuum sealer bags (and a vacuum sealing machine, obviously). I can see the attraction of re-using expensive liquid yeast, but for the 80p or so a sachet of dried yeast costs me it is just not worth the risk of contamination.
 
Over the half century that I have been brewing I estimate that most of my failures with "off" batches have been down to re-using yeast. I now use a fresh sachet of dried yeast for every brew. I keep the cost down by buying 500g packs and re-packaging the yeast in 12g lots using 10 x 15cm vacuum sealer bags (and a vacuum sealing machine, obviously). I can see the attraction of re-using expensive liquid yeast, but for the 80p or so a sachet of dried yeast costs me it is just not worth the risk of contamination.
Out of curiosity, do you just use the one yeast or do you have multiple different yeasts in split 500g bags? And how often do you brew?

If would be nice to do the same as you, but getting 40 X 12g, and doing about a brew a month, it would take me 3.5 years to get through a 500g bag - and that would restrict me to just one yeast.

Even at ~£3 per sachet, it's still worth my while to use fresh yeast (for me, I'm not trying to convince anyone else ) each time.
 
I must admit I have never tried reusing yeast although I’d like to have a go. When I first started brewing I bought liquid yeast and then used slants and build starters for each beer. Not as convenient as dried yeast but I know the yeast is good to go without worrying about possible infections.
 
I could do with some advice about this I have made a wheat beer using gretal yeast from cml and last week I put it in a corny keg and thrown another wheat beer on top of the yeast cake it has been sat in my brew fridge at 25c for around a week and it is only 18% brewed is this normal or should I now be thinking of adding more yeast.

It appears my ispindel is the issue and not the yeast 🤦‍♂️
 
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I've not used Gretel, but that doesn't sound normal. How long did the first fermentation take? Maybe give the fermenter a good swirl to try rousing the yeast? I assume the wort was cooled sufficiently and wasn't racked onto the yeast hot?
 
I've not used Gretel, but that doesn't sound normal. How long did the first fermentation take? Maybe give the fermenter a good swirl to try rousing the yeast? I assume the wort was cooled sufficiently and wasn't racked onto the yeast hot?
Cheers pal for the quick response I’ve been a bit of a tool and was relying on my ispindel so after posting I have taken a gravity reading and it was down to 1.010 which is about Bob on lesson learned not to rely on the ispindel and go old school
 
Yes. Floating hydrometers are good at the original gravity, but completely unreliable on FG, as yeast will get stuck to it and throw it off randomly and unpredictably. It's best to ignore the actual values and use the graph to tell when fermentation has finished (horizontal gradient on the graph)
 
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Out of curiosity, do you just use the one yeast or do you have multiple different yeasts in split 500g bags? And how often do you brew?

If would be nice to do the same as you, but getting 40 X 12g, and doing about a brew a month, it would take me 3.5 years to get through a 500g bag - and that would restrict me to just one yeast.

Even at ~£3 per sachet, it's still worth my while to use fresh yeast (for me, I'm not trying to convince anyone else ) each time.
I brew most weeks, and tend to stick to a single yeast (although I have sachets of others for occasional use). At the moment I am using a 500g pack of GEB's new yeast "Big & Bold" which originated with Whitbread. It is similar to Nottingham, but clears even quicker.
 
When I was experimenting to make the best possible beer for the least possible money I reused yeast - particularly Kveik which I top-cropped dried and then froze. It was easy and It worked perfectly. I also grow my own hops. However you can also buy a selection of 10 CML yeasts for the equivalent of about 90p a packet and i have to say they are fantastic quality and there is a great variety. So you can ring the changes stylewise very reasonably which is a factor. So as others have said - You pay your money and take your choice.
 
I re-use yeast all the time but don’t feel like there’s a lot of effort involved. I have a chronical fermenter (cone at the bottom like a fermzilla) so easy to harvest. Usually put it in a sanitised jar and whack in the fridge. I’ve used yeast that has been over a year old without any adverse effects (although it does take longer to start).

I’m interested in the side effects of over pitching though @Agentgonzo ?
 

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