First shot at yeast re-use.

Armed with a few jugs, some sanitizer, and a few threads from here I tackled reusing yeast (wyeast 1056) for the first time today. Here are some notes/thoughts. Please feel free to comment.

* After 10 min the first jar (1/2 gal) was 80% trub, 20% suspended yeast. Much more solids that I expected. There were two clear and distinct layers, beige solids and yellowish liquid. I decanted and topped of with distilled water to make 1/2 gallon. Decanting from a jug is a PITA. Next time I'll get a turkey baster.

* The second jar separated promptly into 5% solids and 95% liquids. Decanted and topped off again to 1/2 gal.

* I made four 200ml juice bottles with 1/3 glycerin and 2/3 slurry for freezing. Later, I realized that my juice jars are not air tight under pressure (squeezing). I put the unopened bottles into plastic bags and heat sealed then. Refrigerated for 8 hours and placed into deep freeze inside an insulated lunch box w/ blue ice pack.

* I have about 1.5qts in a jug in the fridge. Color is yellow, liquid is clearing, and white yeast are falling out. As it is now, this will end with about 10-20cc of solid yeast. I will draw off water to make 600ml, re-suspend and make 6 x 100ml tubes with 30% glycerin for freezing.

All said and done, it was less complicated and more time consuming than expected. Next time, I may try to completely refrigerate the carbuoy dregs in a wide mouth vessel like a beaker (or possibly a tall, thin one like a graduated cylinder) and manually separate the yeast layer.

24 hours later, the "frozen" yeast is at 5*, but not frozen. If I understand the purpose of the glycerin I don't expect that it will actually freeze.

The bottles I sealed into bags show no signs of leakage after 24 hours. The bags I used to seal the bottles in are 4mil poly sealed with an commercial heat sealer.

The yeast in the fridge has formed a nice whitish 1/4" layer at the bottom of the 1 gallon jug. The liquid is not clear yet, but you can see through it. Looks a lot like a pilsner with chill haze.

I used distilled water in this experiment rather than the boil-n-cool method. At $1.09 and already at room temperature, it saved a lot of work.

Any thoughts on how much liquid to decant off/leave on that yeast in the fridge when I store it? Would you decant to pure yeast and replenish with more distilled water?

pldoolittle said:

Any thoughts on how much liquid to decant off/leave on that yeast in the fridge when I store it? Would you decant to pure yeast and replenish with more distilled water?

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For shorter term storage, I don't think it's necessary to decant and refresh. I've washed my yeast with as few as two "cycles" and they've done just fine. The fluid over your yeast will be a non-factor in color, flavor, aroma...etc.

Where'd you buy your glycerin?

BierMuncher said:

For shorter term storage, I don't think it's necessary to decant and refresh. I've washed my yeast with as few as two "cycles" and they've done just fine. The fluid over your yeast will be a non-factor in color, flavor, aroma...etc.

Where'd you buy your glycerin?

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I noticed that the #3 was pretty much not needed.

Got the glycerin at Publix. Really sucks as they (and Kroger) only carry 6oz bottles now ($2.29). If you can find an old style druggist, you can probably still get 16oz'ers for about the same price.

One Q: My first jug fill (straight from the carbuoy) was about 4" of trub, 1/2 mm of yeast, and 3/4" of yeast in suspension. Is that normal? I looked and looked to see if I was visualizing it wrong, but that's what it was.

Anyone ever try centrifuging the slurry? That should yield a HUGE sample of very pure yeast rather quickly. If you don't hear back, I was probably killed by a makeshift centrifuge spinning 1qt glass jars...

Update: In a different thread, some pictures of the harvested yeast described above:

Here's the link