Author Topic: Dry yeast reuse  (Read 172 times)

DEMPSEY

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Dry yeast reuse
« on: June 05, 2019, 08:11:15 AM »
There is an old saying that paper never refuses ink so applying that to the modern technology of the day, the internet never refuses comment. With that said I'm looking at reusing a slurry from a dried yeast I will pitch in a Lager. I am reading in some comments that dried yeast does not liked to be washed as the drying process has changed it nature. Anyone got a view. :-\
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irish_goat

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Re: Dry yeast reuse
« Reply #1 on: June 05, 2019, 08:59:22 AM »
Washing yeast really just means adding water to try and seperate the live yeast from the trub, dead yeast and hop gunk etc. Can't see how the drying process would mean the live yeast wouldn't still seperate. Given the amount of slurry versus how much yeast you will actually need I can't see how it wouldn't still work.

In saying that, I've re-pitched a ladle full of yeast slurry without washing and had no issues. I saw a commercial brewery repitch directly from slurry as well so it can't be too bad.

Whilst not directly comparable, here's a Brulosophy article were he compares using a clean starter to repitched slurry. http://brulosophy.com/2015/03/02/sloppy-slurry-vs-clean-starter-exbeeriment-results/

Will_D

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Re: Dry yeast reuse
« Reply #2 on: June 05, 2019, 10:17:51 AM »
The live yeasts are the daughters(etc) of the dehydrated yeast and so were never dried
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LordEoin

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Re: Dry yeast reuse
« Reply #3 on: June 05, 2019, 02:17:57 PM »
I've washed many a layer of trub started from dry yeast and never had a problem, even after several generations.
I don't do it much any more because my fridge started to look a little psycho, but i enjoyed it when I did.
it can be a little restrictive if you like trying different yeasts, but great if you have a default yeast that you use most of the time.

Do a good job with your sanitation, and get some big-ass jars for separation and a sack of piss-jars for storage and all is good.
I used big pickle jars, and always wanted larger. Bigger jars allow you to be more selective, especially a tall narrow jar.

Remember that the yeast is still VERY active and even at low fridge temperatures they'll build pressure and pop if you let them. Enough pressure to pop the lid off a plastic piss sample.
When you're about to use the yeast, just give it a sniff before pitching to make sure  there's nothing tart/vingary/acidic/etc.

I've had jars of washed yeast work better than many an experience with vials/smackpacks of wyyeast, whitelabs, etc
Also, getting a few batches out of a pack of yeast makes me a lot happier than feeding the compost bin (and HBS coffers) each time.