Wyeast's Activator smack pack and White Labs' PurePitch pouch are both sold
as "approximately 100 billion cells", and pitching calculators assume it.
It's a nominal figure (labs quote a count at packaging, not what's left by
the time it reaches your fridge), so availableCells lets callers
override it.
Cells in a fresh liquid pack, in billions: 100.
Wyeast's Activator smack pack and White Labs' PurePitch pouch are both sold as "approximately 100 billion cells", and pitching calculators assume it. It's a nominal figure (labs quote a count at packaging, not what's left by the time it reaches your fridge), so availableCells lets callers override it.