Reusing yeast - wash or no wash?

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Sidman

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So I am just finishing packaging a cream ale and want to do another. I prepared a starter with 3 yeast packs wlp 80 (two were close to exp and another was expired) for the first 10 Gallon batch. This time I remembered to cool the batch and dump the trub prior to pitching. I hit the wort with a good full minute of oxygen and the batch took off like a rocket. Fast forward to packaging and I now have two pint sized jars filled with very thick yeast. So I was going to try my luck at reusing this yeast and basically I seem to be confusing myself as to whether or not to wash. It looks pretty clean and my next batch will be two days from now so I was wondering if I should just go ahead and pitch half of one of these pints? I don't think a starter would be needed right? just keep this in the fridge, let warm to room temp before pitching?

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I'm no authority but when I looked in to this recently, lots of accomplished folks were skipping the wash, so I am too.

Feel like I am going to do the same. Are you planning on using yours straight or making a starter?
 
No wash required in my opinion. That jar is more than enough yeast even for another 10 gal mid range gravity.
 
I'm going to start by using the slurry straight and skipping the starter, provided I have enough slurry to do the job. How many cells per mL though? There is guidance on this page and it ranges from 1 to 4.5 B/mL depending on how compacted the slurry is.

http://www.mrmalty.com/calc/repitch.html

As of today I have collected 3 jars but haven't actually USED any yet, though I am new to this.
 
There's probably some fine trub and proteins mixed in. I doubt washing (or more accurately, rinsing) that yeast slurry would separate them anyway.

Just estimate the cell count and pitch. Rule of thumb is to pitch 1/4 of a saved yeast cake. If it's older than say 2 months (stored in fridge), many will advise to prepare a new starter. I've pitched saved cakes after being 4-6 months in the fridge. Just pitched some extra, but not quite half of the original cake.
 
There's probably some fine trub and proteins mixed in. I doubt washing (or more accurately, rinsing) that yeast slurry would separate them anyway.

Just estimate the cell count and pitch. Rule of thumb is to pitch 1/4 of a saved yeast cake. If it's older than say 2 months (stored in fridge), many will advise to prepare a new starter. I've pitched saved cakes after being 4-6 months in the fridge. Just pitched some extra, but not quite half of the original cake.

Thanks much...I likely have more yeast as I just pulled off the two pints so far. That rule of thumb really helps out.:mug:
 
Thanks much...I likely have more yeast as I just pulled off the two pints so far. That rule of thumb really helps out.:mug:

As @Horseflesh said, per Mr. Malty a saved slurry will contain 1-4.5 billion cells per ml. Although that's a wide range, an educated estimate can be made.

If the cake is very trubby, it will be on the lower side. If it's very clean, like yours is after a pre-pitch trub dump, lean toward the higher side, probably in the 2-3 billion cells/ml range, possibly more. If you need 800 billion cells for your new 10G pitch, 270-400 ml of that slurry should suffice. Even a 3x overpitch has no negative effects on the resulting beer, usually. Where some stressing is needed, stay on the lower pitch side.

Good oxygenation helps leveling that field too.
 
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