Repitching Yeast Cake

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jessebymail

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Hi all, I'm feeling unsure about what to do with this yeast I saved. 2 weeks ago when I racked a pale ale I went ahead and dumped the yeast cake and about an 1/8 inch of beer into three separate sanitized tupperware dishes. Then I tossed them in the fridge. I'm planning on using them today for a similar beer. How do I need to go about preparing the yeast for fermentation?
 
If your not going to wash the yeast out of the trub then just bring to room temp and dump it in. I have never kept it like you stated but have racked a batch into the primary on top of they yeast cake (same type of beer) with good success.
 
You can pitch as is, but why would you want to dump old trub into your new beer? You might want to try and wash it up a bit. Check out this article, it'll give you a good idea of how to go about it.

Yeast Washing Illustrated
 
I do this if I know I'm going to brew with the same yeast in a couple of weeks.

I use mason jars, but the process would be the same. Pull the yeast out of the fridge and let it warm to room temp while you brew. You should see some activity as the little buggers start to awaken. When it's time to pitch, just throw them in.

A couple of caveats...
1) If it smells bad after it has warmed, toss it. Try another container, or grab the dry yeast you have stashed in the freezer.
2) If you are brewing a big beer, grab two or three containers.

Good luck.
 
Repitching with or onto unwashed yeast cakes is a bad habit that guarantees some degree of off-flavors. Wash it, or use fresh yeast.
 
Thanks guys, I plan on washing from now on and probably creating a library. Sounds kind of fun and interesting to me. At the time I just didn't want to dump more yeast so saved some. Ive read about washing since and learned a lot from you all. The old cake is warming up now but if it looks unhealthy I do have a packet of dry I can use. Thanks beerkrump I was just worried I was being too simple after reading and hearing all of this about stirplates and libraries and glycol and washing... :confused:
 
Repitching with or onto unwashed yeast cakes is a bad habit that guarantees some degree of off-flavors. Wash it, or use fresh yeast.

I only reuse yeast from low OG brews and transfer almost zero trub from the brew kettle. This means the only thing in my fermenter after fermentation are beer, yeast (dead or alive), and fallen krausen. The same thing that one would find in a starter.

I also do this only when the style of the previous beer is lighter in flavor profile and color.

I have yet to detect any "degree of off-flavors" in my brews that would be associated with this technique.

STM, have you tried this, or had beers that were made utilizing this process?
 
I only reuse yeast from low OG brews and transfer almost zero trub from the brew kettle. This means the only thing in my fermenter after fermentation are beer, yeast (dead or alive), and fallen krausen. The same thing that one would find in a starter.

I also do this only when the style of the previous beer is lighter in flavor profile and color.

These are good points: sufficiently low OG, minimized trub, lighter beer, etc will lessen the negative effects on a repitched batch.

However, the best growth environment for yeast is an unhopped 1.040 OG starter with a pinch of yeast nutrient. How many of your beers fit that bill?

You might not detect off-flavors from your repitching process, or perhaps they're just below taste threshold. It also depends on the beer you repitch into. If you repitch into a big beer that relies on yeast for much of its flavor - a Belgian, for example - you will get off-flavors that you won't detect with a smaller beer. Off-flavors you certainly won't get if you use a sufficient starter from fresh yeast.

Let me be PC and state that taste is in the eye of the beholder. I've got a brew buddy who is on his 5th unwashed repitch onto a cake from Pacman I gave him last fall. The stuff he's producing from it (IMO) tastes like undiluted movie popcorn butter. But he likes it.

For my beers, I'm upping my game, and that in part means more attention to yeast health. So I don't repitch anymore. Had too many almost-good-but-subtly-wrong batches.
 
The beer I got my cake from was close to those conditions, about 1.045 sMash beer with 1 oz fw hops. I did pour the beer off the settled yeast and moxed in boiled water so I could still pour it. Smells good and bubbling slightly. I have some nutrients should I add a tsp when i pitch it?
 
For my beers, I'm upping my game, and that in part means more attention to yeast health. So I don't repitch anymore. Had too many almost-good-but-subtly-wrong batches.

I'm with you on this one, my last couple batches that I have repitched on have been sub-par at best. I'm going with fresh yeast in every batch. Better to spend a few extra bucks, than keep making disappointing beer.
 
I heard a discussion on brew strong about yeast libraries where jamil thought the yeast really didnt perform at its peak until a few batches. Tjis is harvesting krausen and growing starters not trub though.
 
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