No Yeast Slurry Viability Calculator ?

[JIm S.]

How is the group calculating yeast slurry viability?

BF includes date input for Liquid Yeast but not Yeast Slurry calculations per screenshots. Thanks

 

[Josh Hughes]

I listen to the guy that runs White labs. I seem to remember him saying that date your slurry from the day you started fermentation. Putting that in should give you a pretty good idea of viability. If I’m remembering correctly from that podcast.

 

[Donoroto]

A lot of variables in slurry. I’ve had some over 6 months, but I did make a starter.

 

[Flying Weasels Home Brewery]

The help says:

Yeast Slurry:

• Default slurry density is 1 billion cells / mL, but you can adjust it. Some sources say it is as high as 5 B / mL.
• Specify the amount of slurry in Liters.

For the date, I guess the presumption is that it is essentially 0 days old.

 

[JIm S.]

Thanks!

Yes, per Chris White (White Labs Yeast):
- slurry good within 2 weeks of reaching terminal gravity (NOT necessarily slurry collection date),
- reuse up to 1+ month OK (see Donoroto above) but with viability loss,
- starter can (should after 1 month) be performed using a Yeast Slurry Viability Calculator -- ?? BREWER'S FRIEND ??

Currently available slurry viability calculators:
- BeerSmith,
- Brewfather,
- Propagate Labs,
- others.

Thanks again & hope the feedback helps!