This may wind up being a stupid question, but the Android app asks for a use date rather than production date. Am I to enter the “best by” date on the White Labs packet or the production date (which apparently is 4 months prior to the “best by” date)?
It should be the production date of the yeast. Then it will tell you the viability % of the yeast.
Estimated viability, right? Not to be pedantic but there’s no way to know how well each hand treated the sample between leaving the plant and reaching the brewer. I also wonder if Jamil calculates the varying viability drop of each yeast strain, because they are not all the same. Probably not.
But most likely it’s in better shape than you think. Plus, unless we actually do cell counts, it’s all a guessing game and close enough is just fine and dandy.
Yes, the estimated viability. There is no selection for yeast strain. Thus , no accommodation for strain dependant viability changes over time.
As Jim said, unless we do actual yeast counts it’s a guessing game. Yeast is like horseshoes, hand grenades and nuclear warfare, close is good enough