Pitching propagates yeast Q

[nosnhojm20]

I just got a stir plate and 2000ml flask as I delve into liquid yeasts. If I grew up, for example, a 400 billion yeast count starter from a 100 billion yeast count white labs to split 4 ways (4 mason jars or slants or whatever) for later use would that be "slurry" in a yeast calculator like Mr Malty? Or would it be like using the original yeast vial calculations? I would assume the original yeast vial as there is no trub or any other matter in here but am curious.

If this is the case, would the new "date" on the "vial" of propagated white labs be the original or propagated date? I'd assume the propagated date.

Thanks!

 

[GRBC]

It would be slurry.

 

[shtoive87]

If you know the cell count (which you do) it shouldn't matter whether you use vials or slurry. The calculator predicts the beginning cell count from slurry based on density, non-yeast percentage, and viability date. It then figures out the starter size needed to get the necessary cell count for the beer. Whether you use vials or slurry, the starter size necessary should be the same. Viability would be the date the starter reached final gravity.

 

[nosnhojm20]

Great. Thanks!