Re-using yeast from previous batches

mellow11

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I have a few questions about re-using yeast.
1) Is this worth doing? I was told it adds character to the next batch.
2) When adding old yeast to a new batch, do you also add more fresh yeast?
3) If so, how much?
4) How many times can this be done? I was told a local microbrewery does this 7 times before dumping.
5) If kept in the frig, how long will it keep?
6) Can different old yeasts be combined, or must they be kept separate?
Any answers or suggestions would be appreciated.
 
I'd like to hear what some the veterans have to say about this. It seems to me that yeast is what gives a lot of beers their signature aromas and taste. And I've heard the same thing that reusing the yeast from a previous batch makes a better brew... I'm all ears.
 
I have a few questions about re-using yeast.
1) Is this worth doing? I was told it adds character to the next batch.
2) When adding old yeast to a new batch, do you also add more fresh yeast?
3) If so, how much?
4) How many times can this be done? I was told a local microbrewery does this 7 times before dumping.
5) If kept in the frig, how long will it keep?
6) Can different old yeasts be combined, or must they be kept separate?
Any answers or suggestions would be appreciated.
1) yes, depending on your set up..."character" is not what I'd call it. Better, cleaner beer from (potentially) healthier yeast is what you get.
2) no, generally speaking
3) see above
4) at least several times, but totally dependent on your methodology. I repitch trub directly 3 times or so because I don't have full-sanitary accommodations. Breweries can harvest, store and propogate yeast without it ever coming into contact with the outside environment. Most homebrewers can't.
5) Couple of months is pretty reliable without a starter, depending on volume of trub
6) could be but should be necessary. All the trub or yeast cake from a 1-2 gallon batch is enough yeast for a 5 gallon batch easily and trub from a 5 is more than enough for 10 gallons. Lagers require a lot more and generally it's better to make a starter no matter what but ale yeasts can be warmed and repitched direct from the fridge and do pretty well.
Others will add more detailed and experience.
 
Yes, it is worth doing. Where I am a pack of liquid yeast runs me $10.50, if I reuse it from a previous batch then my per batch cost is $5.25, and goes down more with each successive batch. You do not need to add new yeast along with the old, provided you add a sufficient amount (use the yeast pitch calculators here to know how much to use).
I agree with JA that reuse depends on your ability to maintain sanitary samples. I usually don't do more than 3 generations, and if you are just starting out in reusing yeast you might want to keep your number low until you are more sure of your ability to keep things clean. If you have a good clean yeast sample and you can make a starter, then there is no reason to combine yeasts, it will work, but because you don't know which yeast (if any) might dominate the fermentation then the character of the resulting beer is a bit of a crap shoot.
 
Thank you J A, I appreciate the information very much.
I will do this in a day or two from the primary fermentation I just transferred to the 2nd.
The yeast was Nottingham.
I have a fair bit at the bottom of the pail.
Next one will also be an ale.
I see that you are a "well-known" member.
Greetings, wise one!
Due to the cost of yeast, and the batches I must produce to stay ahead, this information alone is worth the cost of premium membership.
So, thanks to you, I will sign up tomorrow.
 
Thank you to you, too, PJW (if I may abbreviate).
I see you are also a veteran member.
I appreciate the help.
Point taken that combining different yeasts could be tricky. So, I will keep them apart for now.
It will not be a problem because, right now, I'm only working on two types of dry yeast - Nottingham for ale, and Classic English ESB for IPA. Both from Lallemand.
I'm fussy about sanitation - can't run the risk of messing up due to carelessness.
I'll try one repeat and go from there.
As I said to JA, the savings will pay for the membership, so what's not to love about that?
I see you are in Montreal.
I'm more north, up near Mont Tremblant. Ski-country heaven, if you're into that, but also many hidden, fertile valleys with farms, white-water rivers, lakes, cows, sheep, green pastures and haystacks, surrounded by ancient mountains.
My thing, and Heaven too.
So, merci beaucoup, mon ami.
 
I pitch directly on my last beer without saving it all the time, it's actually too much yeast and can build too much krysen so in that case I always keep the temp low not to excite the happy creatures and go wild, other than that I don't save trub but I do build multiple staters and sometimes end up with 6 - 45mil's of pure slurry out of a 3 lb bag of dme from one yeast pack, saving slurry can be risky unless your a clean freak, always smell it before you brew, it shouldn't smell like an armpit or dirty socks
 
Thanks Ozarks Mountain Brew Moderator.
I understand that this can accumulate fast, and overwhelm the purpose of re-use.
But, as I said to JA and PJW, I will go at this carefully according to my ability to keep getting good results.
I haven't lost sight of the point that good beer is more important than cutting corners on methods to save money.
But if re-using yeast can produce a better beer, then why not?
I'm fussy about sanitation. Sanitize everything and rinse 3 times.
Luckily, water is not problem - clean, pure, abundant spring-fed water. Probably the same for you in the Ozarks, yes?
Thanks for the tip about smell - that applies to just about everything doesn't it?
I'm new at this, so forgive the ignorance.
Thanks for your time and reply.
 
I pitch directly on my last beer without saving it all the time, it's actually too much yeast and can build too much krysen so in that case I always keep the temp low not to excite the happy creatures and go wild, other than that I don't save trub but I do build multiple staters and sometimes end up with 6 - 45mil's of pure slurry out of a 3 lb bag of dme from one yeast pack, saving slurry can be risky unless your a clean freak, always smell it before you brew, it shouldn't smell like an armpit or dirty socks
Ummm... the yeast I pitch totally smells like dirty socks. Its munich by danstar and I've had no problems with the put come but it totally smells like dirty socks.
 
But if re-using yeast can produce a better beer, then why not?
it will not make a better beer but it will keep cancistancy if your brewing the same type of beer over and over, the time to stop is using saved yeast is about 6 months in the fridge but I still advise a test with sugar which should produce foam in at least an hour or a starter after saving for a week, good luck anyway whatever you try
 
Ummm... the yeast I pitch totally smells like dirty socks. Its munich by danstar and I've had no problems with the put come but it totally smells like dirty socks.

yeah that's a signature of that brand when it's too warm or mishandled but it can smell off in the fermenter sometimes and that's ok, just not saved yeast, it's hard to describe what it should smell like, you'll know it when you've smelled it several times
 
Thank you to you, too, PJW (if I may abbreviate).


I'm more north, up near Mont Tremblant. Ski-country heaven, if you're into that, but also many hidden, fertile valleys with farms, white-water rivers, lakes, cows, sheep, green pastures and haystacks, surrounded by ancient mountains.
My thing, and Heaven too.
So, merci beaucoup, mon ami.
Mont Tremblant is a beautiful area. I love the country but in the end I am a city boy at heart. Welcome to the forum.
 
Mont Tremblant is a beautiful area. I love the country but in the end I am a city boy at heart. Welcome to the forum.
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it will not make a better beer but it will keep cancistancy if your brewing the same type of beer over and over, the time to stop is using saved yeast is about 6 months in the fridge but I still advise a test with sugar which should produce foam in at least an hour or a starter after saving for a week, good luck anyway whatever you try
Too true, PJW, country life is not for everyone, but we live in times when it can all go to hell over a weekend. Friday, life's good, Monday WTF happened?. It helps for peace of mind to have a back-up plan, but that's for another forum.
Thanks Ozarks moderator, because that's my idea - to make the same beer often, if it's enjoyed by all my family and friends. So re-using the same yeast could work well. Time will reveal all.
So far, my output at 5-gallons per has been appreciated, so I'll re-use my yeast for my ale and IPA and see how that goes.
Next step 15-gallons.
Thanks to you all, and a very good night.
 
I reuse yeast lots, I've even started banking samples for freezing. I reused BRY-97 probably 10-12 times before I stopped and that was mostly just to try something different. As long as you don't do something to wreck it you can get a lot of mileage out of yeast. I actually prebuild a starter before hand and then pour about 250ML of it into a mason jar to save for the next time, it's easier than washing yeast. But if I have a carboy freshly empty and I'm making a new batch I may just transfer right on top of it.
 
Thanks a lot, Hawkbox. When you refer to a starter, I presume you are using liquid yeasts. I have been using dried yeasts. I understand that starters are useful for re-used liquid yeasts while not for dry yeasts, due to the greater cell content in dried - 230 billion vs 100 billion for liquid. Is this correct? In my last batch of ale (from dry Nottingham), now in secondary, I got 750 ml of trub which is now in my fridge, waiting for the next batch of the same ale in a day or so, which I plan to try for the first time. Is this a mistake, or should I have washed this trub before storing? Excuse my lack of knowhow, but this is the first time I'm encountering this situation, as a newbie devoted to making great beer. Usually, the best answers come directly from those with experience who are willing to teach. Thanks.
 
I do either. If you make a starter you just put it in a mason jar and put it in the fridge. I don't tend to worry as much with dry because it's way cheaper but I am still perfectly willing to do it.

You're not going to make it any worse for yourself with what you have, my first attempt was washing and I hated it so I "invented" the idea of just saving some of the starter. If you're straight pitching and don't care about saving yeast I'm mostly in the camp that you really don't have to care unless you're doing an Imperial level beer, (like 8%+). I only started doing this a year ago so I'm far from an expert.

Doing a starter will however bulk up your yeast if you want that. You're going to get a lot of conflicting opinions on this topic and I honestly don't know what the right answer is. If you haven't already I'd suggest you check out brulosophy.com they have a lot of good "exbeeriments" that beginners like you or me can benefit from.
 
I got 750 ml of trub which is now in my fridge, waiting for the next batch of the same ale in a day or so, which I plan to try for the first time. Is this a mistake, or should I have washed this trub before storing?

It's generally safe to use the old trub as-is for the same or similar beer styles. If you're using the yeast to do a completely different style, washing will help eliminate unwanted hop and malt flavors from the previous batch.
https://www.brewersfriend.com/2010/01/30/yeast-washing-101/
 
Thanks KC. Yes, I plan to use the trub for a similar ale to avoid using a new pack of yeast. I will get around to washing soon as my confidence develops. Thanks for the link.
 
After you do it a few times you'll get comfortable with it. The only real time I would put a hard no on reusing yeast is if I had hopped the piss out of the beer. I just don't like dealing with leftover hops in reused yeast.
 

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