I will give two examples of yeast cell count. First one is 0.34 B cells/ml in 6 liters of wort starter with just a few amount of slurry cake. 2nd one is 1.46 B cells/ml in 1 liter of starter including Wort+Slurry.

So when it comes to total number of yeast cell calculation,do i need to multiply yeast count with 6 liters of wort or a thin layer of slurry which is 300 ml ??

So total yeast count is 2040 billion cells in 6 liters or 102 billion cells in 300 ml of yeast slurry ??


  • Is the cell count specific to the yeast slurry that is then mixed into a larger amount of wort - or was the wort pre-mixed and a cell count taken of the total mixture? If the yeast cell density count is for the slurry alone then the total cell count is given by multiplying the cell count (per mL) by the mL of slurry used. Commented Jul 23, 2018 at 9:50
  • Is this two samples of the same starter? Before and after removing wort? If so you should cold crash the sample and decant off the wort. Then mix the slurry and sample that. Commented Jul 23, 2018 at 14:15
  • @barking.pete yeast count is after shaking slurry with new wort. Sometimes i took from 1 ml of slurry portion and count. Then for total cell count,it is slurry alone or mixed with wort ? I'm so confused. And there may be yeast cells wort also right? Commented Jul 24, 2018 at 4:47
  • @EvilZymurgist two sample is using same starter. Is yeast count different after cold crushing and decanting wort ?... Do yeast count reduced after decanting wort ? I'm just worried about that !! Commented Jul 24, 2018 at 4:50
  • @ThantHtooAung there will always be some left in the wort after a fast cold crashing, but that can be wort can be saved and the yeast will settle out over a week or so, and makes for a good starter next time around. Commented Jul 24, 2018 at 4:55

1 Answer 1


If you are combining the starters you have:

  • 0.34B/mL @ 6L = 2040 Billion
  • 1.46B/mL @ 1L = 1460 Billion
  • Total Yeast Cells Combined = 3500 Billion @ 7L

After combining the starters, cold crashing will cause most of the yeast to drop out and form a nice, compact yeat cake/slurry at the bottom. There are going to be residual yeast cells in solution above the cake, however, in my experience after several days in the fridge almost all the yeast is at the bottom. I decant the excess solution, leaving a small amount.

In this example, if I cold crashed this 7L starter for a few days, decanted 5 L off the top I would then say for simplicity sake that I have 3500 Billion @ 2L.

  • Now i m very clear with your explanation and i ll start doing like as u told me !! Thx Commented Jul 31, 2018 at 3:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.