Culturing Zero Viability Yeast (Derived from Yeastcalc)

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Fat Bastard

Brew Cvlt Doom
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So, a while back I was given a vial of Czech Lager Yeast that was out of date. Yeastcalc reckons it's got zero percent viable cells.

Now back in the day when I used to not care about such things and everything got a 2l starter, I managed to culture up similarly out of date yeasts and make them produce beer of a drinkable (and sometimes club comp level prize winning) beers. If I worried about it, i gave it a few days extra on the stirplate.

I'd like to be a bit more scientific about it this time.

Is it just a matter of mucking around with the date/initial cell count until it calculates something that you can step up until you get the required 480-500 billion cells? or is it more involved than that?

Cheers,

FB
 
With weak or old yeast, best to use a low gravity for the initial steps, ~1020

Probably a good idea to rinse as well.

Start out 100ml then to 500ml if you're getting some action and good behaviour, rip it up to a 1040 2lt,

Give it a good rinse at that point and freeze some off ;)
 
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