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Yeast/Starter size calculator

x3la

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I am creating a starter from a Slope/Slant.

Cell Colony -> ~ 5ml test tube of DME wort = ~ 50 million cells (10M/ml)

I want to create a liquid "Yeast" in BeerSmith so that I can associate it with my Recipe and have it create my starter sizes accordingly, so I enter "Cells Per Pack", as 0.05 billion (50 million).

When I hit save the value is displayed as "0.1" yet when used in a recipe as a starter appears with "0.05 Billion viable cells" as expected (seems there's a bug in the yeast tab display on values less than 0.1?).

The "Starter" section of the recipe seems unable to calculate starter sized for such a small number of viable cells, however the "Yeast Starter" tool is able to calculate starter size needed and DME required.

This might be a bug in BeerSmith's handling of 2 decimal places in the Yeast Ingredient and Recipe/Starter section?
 

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Not a bug, just rounding for display.  The underlying calculations all will use the original .05 M/5 ml as added by your yeast profile.  I do this all the time when doing cell counts.  I may have a cell count of 0.625 B/ml of yeast and enter it that way in the starter page.  The starter will display 0.6 B cells only, but the calculation for quantity always works out such that the program is using the 0.625 B number.

Using such a small number will cause the starter section a problem.  There is a limit to the number of times cells will replicate (somewhere around 5x) so the cell growth is capped.  When I take colonies off a culture plate, I will scale them up in 5 ml of 1.020 wort to start and then increase the volume to 10 ml.  From there, I transfer the contents into 25 ml of 1.036 wort before pouring that into 100 ml of the same wort.  At this point, I have enough cells to give me 30 B to 50 B cells which will scale up on the starter tab using a standard starter size a lot more easily.
 
Oginme said:
Not a bug, just rounding for display.  The underlying calculations all will use the original .05 M/5 ml as added by your yeast profile.  I do this all the time when doing cell counts.  I may have a cell count of 0.625 B/ml of yeast and enter it that way in the starter page.  The starter will display 0.6 B cells only, but the calculation for quantity always works out such that the program is using the 0.625 B number.

Using such a small number will cause the starter section a problem.  There is a limit to the number of times cells will replicate (somewhere around 5x) so the cell growth is capped.  When I take colonies off a culture plate, I will scale them up in 5 ml of 1.020 wort to start and then increase the volume to 10 ml.  From there, I transfer the contents into 25 ml of 1.036 wort before pouring that into 100 ml of the same wort.  At this point, I have enough cells to give me 30 B to 50 B cells which will scale up on the starter tab using a standard starter size a lot more easily.

Thanks for your reply. I'll do the same then and scale up to 100 - 200ml before considering it my Starter in BeerSmith.

Do you have any insights on the purpose of the 'Slant' form in BeerSmith? what does it change?
 
To my knowledge, setting the yeast type to 'slant' changes the viability of the yeast to default to 50% and the number of cells per pack to 0.1 Billion.  Beyond that, I don't know what other implications it has in the software as I have never played around with that setting.  I always worked the picked colonies up using the method I described before hitting them with a bigger starter.  It seems to work just fine when I do a cell count on the finished starter to measure out the volume of yeast slurry needed for the batch I am brewing. 
 
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