How long can yeast cake sit in fermenter before reusing?

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NickinWI

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I racked a low gravity brown ale off Safale S-04 yeast cake in my 6 gallon glass fermenter on Monday night this week. I am planning on brewing a 1.092 OG Imperial Stout on this coming Sunday, and I would like to just dump the fresh wort onto the yeast cake I've got.

I racked MOST of the beer of the cake, and I was careful about sanitization, and I've replugged the carboy with the original bung.

I'm wondering if it is OK to go for it sitting in my 68*F basement, or if I should toss it? The cake is thoroughly damp, but it hasn't been covered in liquid and it hasn't been kept cold. Smells fine, well good really. :)

I don't have yeast starter eqpt, so I didn't bother washing and making a starter etc.

:mug:

Thanks,
Nick
 
If there's an inch or do of beer on the cake, it's probably okay. Can you whip up a quart or two of 1.040ish wort from extract and put it on the cake like a starter? that might help to ensure that the yeast stays good.

In the future, you can always pour the cake into some sanitized beer bottles and cap them for use later.
 
I would have recommended you put that yeast cake into sanitized quart size jars and into the fridge right after transferring your beer. I would be fine for a few weeks this way with little chance of additional infection. This is what you should do in the future.

My concern with your yeastcake in the carboy would be the air that was allowed into the carboy when you transferred out the brown ale. I'm sure the viability is still totally fine. However, all that beer space was replaced with unfiltered air which could have included a number of microbes.

You either cross your fingers and use it, or you buy a few packets of dry and play it safe. It's your call. Gambling is fun when it works out :D
 
personally I wouldnt risk it for the few $$ S-04 costs. any reason you didn't just wait til closer to brewday?
 
personally I wouldnt risk it for the few $$ S-04 costs. any reason you didn't just wait til closer to brewday?

This is one of those events that highlights my well polished planning skills. :D

Honestly I wasn't really sure what I was going to brew... My plan was to just dump the yeast, but I put together a recipe and I figured with the high OG, I would be better off using the yeast cake if I could. Hence my post!

Thank you for all the great tips & tricks here! :rockin: In the future I'll be able to do a better job with saving/reusing some yeast.

I'm not concerned with the cost of 2 packets of yeast, vs the risk of losing all the work/expense of an 18.5lb grain bill. I want to play it safe.

Would 2 packets of S-04 be able to cope with this wort though?
 
Toss it. Like someone else said, not worth the risk. If, on the other hand, you don't care about beer quality, keep your slurry for as long as you like and pitch it.
 
Would 2 packets of S-04 be able to cope with this wort though?

Two packs of properly rehydrated S-04 (see product sheet instructions for rehydration here: http://www.fermentis.com/wp-content/uploads/2012/02/SFA_S04.pdf) could give you 20b cells per gram X 23 grams = 460 billion-ish cells. I'm assuming you want to ferment about 5.5 gallons of 1.092 wort. So you need about 1 million cells per degree Plato (your beer is 23-ish degrees P) per ml of wort (21,000) which takes us to 483 billion cells. So you are likely okay with 460 billion, especially if your fermentation conditions are good. My only question about this yeast would be alcohol tolerance but a quick search suggests you are probably fine there too. It might be worth checking into yourself.
 
Dear R2D2.

I had a 4 month old yeast cake that was all dried out and cracked. It jumped right to life and made great beer.

If it smells fine and looks fine, it is most likely fine.

I would use 1/2 cake at MOST though. Usually 1/4 cake is my goto. A whole cake is overpitching for any beer.
 
Thanks for the advice osagedr and cheezydemon3!

I've managed to bung up enough things lately, so I will play it safe and just pitch the 2 packs of rehydrated yeast. Looks like it should be enough cells to get the job done!

NEXT time though! NEXT time!
 
On a side note:

You mentioned that you're brewing a 1.092 Imperial Stout using S-04. Obviously I don't know what your process will be but I do know that S-04 had a tendency to drop out quicker than you might expect, and you might be left with a higher gravity than you're hoping for. Just wanted to mention that as it might alter your yeast purchase.
 
The options are endless..... welcome to the wonderful world of brewing :D

To get an 8.5% abv beer starting at 1.092 you'd finish about 1.028 which, IMHO, would be awfully sweet. Granted, you're probably after a sweeter finish with an imperial stout but I doubt you're after that sweet. Maybe 1.020-ish would be good but you'd be looking at an ~9.5% ABV brew.

Rather that pinpoint a starting gravity, why not provide a listing of characteristics you're hoping to get from your stout. From there, I'm sure we all can help guide you into a direction that will work for you. Not to mention, there are many fantastic recipes posted in the recipes section that might just fit the bill.
 
Thanks St Pug, I know there are basically a billion different yeast options! Haha I pulled the recommendation of S-04 from a northern brewer RIS recipe.

I'm trying to make a clone of Central Waters Peruvian Morning.

It is a fairly light bodied beer, its a BA coffee added stout, not terribly sweet, bitter, or syrupy.

I would really appreciate advice!

I wrote this recipe but haven't gotten any feedback.

https://www.homebrewtalk.com/f12/re...eruvian-morning-ba-coffee-stout-clone-424673/
 
After looking at your planned recipe, I'd actually say roll with it. It looks solid from my perspective. If it doesn't work out exactly as expected then at least you have a starting point to make adjustments.
 
Thanks St Pug. Ended up modifying the recipe at the LHBS, and screwed up my volumes lost vs volume into fermenter.

I rehydrated two packets of S-04 and used servomyces and oxygen. Wort was bubbling away really well this morning.
 
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