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General Category => Yeast and Fermentation => Topic started by: roguejim on April 07, 2010, 07:57:14 PM

Title: Yeast Washing 101
Post by: roguejim on April 07, 2010, 07:57:14 PM
I've never had reason to use the yeast washing procedure until now.  Due to recent changes in my brewing process, I collect a large amount of trub in my fermenter. 

My questions: After dumping the trub/yeast from the fermenter into a 1gallon jar, how long should I let it settle out before pouring off the viable yeast?  Should I refrigerate it during the settling process?  Would it be safe to say that the more trub in the jar, the longer I should let it settle out?  Thanks.
Title: Re: Yeast Washing 101
Post by: Hokerer on April 08, 2010, 01:18:18 AM
Generally, once you poured it into the gallon jug, give it 20 -30 minutes.  Most of the junk will have settled on the bottom but you'll still have way cloudy liquid above that.  Pour off that liquid into as many jars as it takes and refrigerate them.  The next day, each jar will have a layer of relatively clean yeast on the bottom.  Decant the liquid off the top and collect and pitch the resulting slurry.
Title: Re: Yeast Washing 101
Post by: roguejim on April 08, 2010, 08:28:35 AM
Thanks for that.  I'm surprised at the 20-30min settling period...Seems long, but what do I know.
Title: Re: Yeast Washing 101
Post by: tygo on April 08, 2010, 10:47:27 AM
I've let it settle out for 24 hours in moderately cold weather then poured it off.  The yeast I got from decanting looked very good, but there wasn't all that much there.  When I do it again I'd probably go more with what hokerer posted above and settle for a little extra trub.
Title: Re: Yeast Washing 101
Post by: majorvices on April 08, 2010, 03:09:01 PM
I tried washing yeast several times and, IMO, I see no advantage to washing the yeast on the homebrew level. Just an extra step that could compromise sanitation. Just keep most of the hops and trub in the kettle and collect and pitch part of your slurry and you will be fine.
Title: Re: Yeast Washing 101
Post by: dee on April 08, 2010, 05:07:10 PM
I follow the same procedure.  I use the 200 micron bucket screens to filter hop and break material and I always end up with clean yeast cakes.  The rinsing process isn't worth the additional risk or effort in my opinion.  I've never been able to tell the difference between rinsed and bulk harvested yeast in the final product.       
Title: Re: Yeast Washing 101
Post by: hankus on April 09, 2010, 01:04:50 AM
I also am tilting back to the minimal wash approach..rack as much GOOD beer as possible,add a little sterilized water (8oz) swirl around and in a couple of minutes withdraw 16 oz of liquid,cover loosely and into frig.I am right now building a starter from a 4 mnth old capture and it's doing well.
Title: Re: Yeast Washing 101
Post by: beersk on April 09, 2010, 03:19:00 AM
I tried washing yeast several times and, IMO, I see no advantage to washing the yeast on the homebrew level. Just an extra step that could compromise sanitation. Just keep most of the hops and trub in the kettle and collect and pitch part of your slurry and you will be fine.

Sure there's an advantage.  It's great to be able to have yeast on hand just like hops when you want to brew a batch and not have to pay 6 bucks for a smack pack when you can pay 6 bucks once and get 16 batches, at least, out of one pack.  It makes a lot of sense on the homebrew level. 
I plan to start washing and reusing my yeast as well.  I have a smack pack of 1272 in the fridge I plan to reuse over and over and over.  That's good yeast.
Title: Re: Yeast Washing 101
Post by: tygo on April 09, 2010, 03:57:22 PM
Majorvices isn't saying don't reuse yeast.  He's saying he doesn't see the value in washing it as opposed to just collecting and saving a part of the yeast cake without washing it.
Title: Re: Yeast Washing 101
Post by: denny on April 10, 2010, 03:31:33 PM
Majorvices isn't saying don't reuse yeast.  He's saying he doesn't see the value in washing it as opposed to just collecting and saving a part of the yeast cake without washing it.

+1!  I do as Majorvices.  Like him, I reached the conclusion that washing is a PITA for no appreciable benefit.
Title: Re: Yeast Washing 101
Post by: uthristy on April 11, 2010, 11:05:07 AM
Another +2  for a PITA and added chance for contamination.
Title: Re: Yeast Washing 101
Post by: beersk on April 12, 2010, 03:58:23 PM
Majorvices isn't saying don't reuse yeast.  He's saying he doesn't see the value in washing it as opposed to just collecting and saving a part of the yeast cake without washing it.

Okay, I see now and I agree.  I misunderstood it before. 
Title: Re: Yeast Washing 101
Post by: weithman5 on April 12, 2010, 04:03:43 PM
when you have a pack of yeast you like you can always save some when you make your starter and use it to propagate a fresh line. similarly, you can make two starters from one pack and propagate up one for brewing and one for storing. then you will always have a "clean"  source of your favorite yeast
Title: Re: Yeast Washing 101
Post by: majorvices on April 13, 2010, 12:26:05 PM
Yes, I'm a huge proponent of reusing yeast. Just not washing yeast.  ;)
Title: Re: Yeast Washing 101
Post by: mainebrewer on April 13, 2010, 03:23:55 PM
I generally re-use my yeast.
I'm curious, assuming that the starter is the first generation, how many generations do others use?
Title: Re: Yeast Washing 101
Post by: majorvices on April 13, 2010, 03:48:49 PM
3-4 for me. Sometimes I also just collect the slurry and make several starters off that slurry on my stir plate.
Title: Re: Yeast Washing 101
Post by: denny on April 13, 2010, 03:50:50 PM
I generally re-use my yeast.
I'm curious, assuming that the starter is the first generation, how many generations do others use?

At least 3, often 5, sometimes more.
Title: Re: Yeast Washing 101
Post by: weithman5 on April 13, 2010, 03:55:16 PM
probably half dozen off a single starter. but i am still a fan of propagating/culturing part of what you buy so you will always have a first or second generation to use as a starter.  similar, if not easier, than culturing from sediment of a production beer.
Title: Re: Yeast Washing 101
Post by: Matt B on April 13, 2010, 04:07:46 PM
When I get a new vial, I usually make a starter, and split it into two bottles. One goes into storage, and I'll take the other one, pitch it, and pitch the remaining yeast cake maybe 3 or 4 times. After that I just get too nervous about contamination. And quite often I want to make a different beer that requires a different yeast. When I'm ready to go back to that original yeast, I'll take that second starter that went into storage, build that up and depending on how energetic I feel, I'll save some of that into another bottle that'll go into storage and pitch the rest, take that 3 or 4 times, etc etc. Needless to say, I don't buy yeast very often.

However, I realized that I had a couple of bottles of wlp007 in the yeast fridge. I haven't used that in a while, it went into the fridge August. Hmm. Probably dead, but heck, let's try to build it back up. Poured off the liquid, shook up the yeast on the bottom, poured it into a flask with a little bit of basic wort. Sat it on the stir plate over night. Next morning, looks nice and cloudy, was about to wash the yeast (since it had been sitting around for quite a while and there's probably tons of dead yeast in there that I didn't want to contribute to off flavors if I pitched it) and took a whiff .. WHOOOO. That isn't yeast that's growing in there. If you've ever done the off flavor tasting kit from Siebel, this is straight from the vial of ethyl acetate. If the girlfriend was around I would've had her put her finger in it and I'm guessing the nail polish would've dissolved right off. I'm not entirely sure what causes it, but needless to say, it went down the sink. And i've sanitized my equipment. Twice.

Lesson: If it doesn't smell like yeast. Don't use it. Six bucks for a fresh vial is worth not ruining a $20 batch of beer.

Title: Re: Yeast Washing 101
Post by: a10t2 on April 13, 2010, 06:57:19 PM
Actual repitching, I've only gone three generations. I just don't brew enough to do it very often.

Propagating from a slurry though, I've re-used my 1056 culture 11 times so far, generally with several months in between. I don't consider that a new "generation" each time though, since it's only fermenting 1.030ish starter wort.
Title: Re: Yeast Washing 101
Post by: mainebrewer on April 15, 2010, 05:53:29 PM
Thanks for the replies.
On average, I brew every three weeks.
I alternate between WLP001 and WLP002 (occaisionally 005 or 007).
I've been filling a quart Mason jar after the initial ferment and then six weeks later using a portion of the jar.
I guess I'll start saving some slurry from the second and third ferment as well.
Assuming good sanitation, I wonder how long it would be before there was a negative effect from mutation?
Title: Re: Yeast Washing 101
Post by: majorvices on April 16, 2010, 12:07:12 PM
It depends on the  strain and gravity of the beer and how well you aerate... nutrients.... etc. I feel comfortable ~3 generations but not so much because of mutation, rather I feel less comfortable about the sanitation of the strain after that (either that or I am at a high gravity and I don't repitch from much higher than 1.070.)
Title: Re: Yeast Washing 101
Post by: blatz on April 16, 2010, 01:53:15 PM
I wonder how long it would be before there was a negative effect from mutation?

FWIW, I only get new yeast about twice a year (unless its a strain specific to the beer I'm making) I save from 1st and second pitches (which is actually 2nd and 3rd since i get brewpub yeast a lot) and then branch off of those to 4 generations, regrowing if I have to b/c its been too long.

so point is, you can go a good long while if you keep good sanitation practice and brew often enough to keep the yeast healthy.
Title: Re: Yeast Washing 101
Post by: denny on April 16, 2010, 03:21:42 PM
Assuming good sanitation, I wonder how long it would be before there was a negative effect from mutation?

Mutation takes quite a long time, AFAIK.  Sanitation is the real concern.
Title: Re: Yeast Washing 101
Post by: b-hoppy on April 17, 2010, 01:59:40 AM
back in the 90's i was doing 10 gal. each week.  on friday i'd rack, and saturday the new beer went right in on top of the dregs.  great for a couple months - then i noticed the beers were coming out more bitter than calculated.  freaked me out. (all i make is ipa's).  then, got working for the railroad, no schedule, on call 24/7 and what little time i have is precious - brewing was on the back burner.  couple years ago, things changed and i had some time to get back brewing and i also got one of these here fancy computers.  things changed in the homebrew world since my setback.  these forums saved my sanity when i saw a post about rinsing/washing yeast.  apparently my sanitation is o.k. because i'll run a yeast for 20 or 30 repitches or until i get the urge to change with no problems.  time is the concern.  i don't know when i'll be able to have some time to brew let alone make a starter, so having a couple mason jars filled with 'ready-to-go' yeast was a real blessing. sure, it'll get a little bitter after 10 or so batches of ipa but most of the time i'll brew a 'sissy beer' to give to my sissy beer drinking friends and when i harvest THAT yeast, it's like having a new/clean pitch.  i guess it all depends on your situation.
Title: Re: Yeast Washing 101
Post by: mainebrewer on April 20, 2010, 08:43:09 PM
Yeah, I really like having a jar or two of slurry in the 'fridge for those times when I find I can brew on short notice and don't have time to make a starter.
Of course, I keep a couple of packs of dry yeast around for the same reason. Gotta have a plan B!