Yeast slurry density

[philjohnwilliams]

When using the yeast pitch calculator with yeast harvested from a previous batch, you have the option of selecting the slurry density. The default setting is 1 billion cells/ml, but how does one determine the density of the slurry? I have 100ml of a dense cake from a previous batch that was harvested 5 weeks ago. Any ideas as to what the density might be, or an easy way to calculate it?

 

[Yooper]

That looks pretty clean without alot of trub in there, so if it was me, I'd use the default. If you have lots of trub, I'd go with less than the default depending on how much visible trub you see. For example, if there was 25% visible trub, I'd cut the default by 25%.

Without a hemacytometer, it's a guestimate.

 

[GFHomebrew]

Yep wish my yeast samples were that clean! What ever method your using phil stick to it.