Reusing Yeast

[BrewersApprentice]

Hey All, i've noticed in a few posts/replies that you can reuse yeast how is this done as iv only used kits yeast? (so sprinkle on top)

[rotten]

look here viewtopic.php?f=2&t=10744

check out the link drsmurto posts and join the discussion if you like. I'm currently making a liquid starter at the moment using his advice. I cup of yeastcake works wonders too.
Good luck

[melykabeer]

I just used 1 cup of yeast cake that I had stored in a stubbie and sat at the back of the fridge since January. Was harvested from brew using a dry pack of us-05. Seemed to take off after 48hrs. They seem to store ok fine for months

[emnpaul]

It will work after a few months or more, yes, but whether it works fine I think is debatable. A cup of slurry pitched at an appropriate temperature after a week or two should start to do it's thing in about 6-8 hours in a fairly standard gravity wort, i.e. between 1040-1055.

Harvested yeast will start dying off almost immediately and by the time a few months rolls around your viability rate will be pretty low, as evidenced by your extended lag time. Judging by your lag I'd say youve pitched equal to or less than what you'd get from a pack of fresh yeast sprinkled on top of your wort along with a large quantity of dead yeast and probably some trub from your last batch. I'm not telling you not to do it but you might want to give some thought to whether or not you'd like to do that to your (and I'm not singling you out, I mean every one) lovingly crafted brew.

[melykabeer]

Good point. I saw the thick foam ontop in the fermenter and assumed its all good.

If I ever do this again I guess a starter would be the way to go?

[emnpaul]

I mostly use liquid yeast and reuse it on a regular basis. If I'm storing it for more than a few weeks I wash it as per Dr. Smurto's instructions and depending on how much I have saved or how long it has been stored I sometimes make a starter.