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Issue with Yeast Starter Calculation

Oginme

Grandmaster Brewer
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I picked up a thread from HBT where the user is having a problem with the 'starter' tab.  When entering the volume and gravity of the yeast starter, the calculator presents a value for the estimated number of cells produced. Further changing of the gravity number for the starter wort recalculates the estimated amount of DME required but does not affect the calculation for the number of cells produced.  I can set the gravity down to 1.020 and it will not change the 'yeast cells with starter' calculation at all.  The volume of the starter changes the calculation, but the starter gravity does not.

Edit:  Just for noting, this function did work correctly in BS2. 
 
I am making a starter today so I checked this. The gravity of the starter does nothing to the cell count.

Furthermore, the cell count seems to max out at a certain volume. My yeast cells needed for this batch reads 363 billion. If I increase the Starter Size the Yeast Cells with Starter figure goes up until I get to about 2.35 L where it hits 334.9 Billion and stays there no matter how much bigger I make the volume.
 
Kevin58 said:
I am making a starter today so I checked this. The gravity of the starter does nothing to the cell count.

Furthermore, the cell count seems to max out at a certain volume. My yeast cells needed for this batch reads 363 billion. If I increase the Starter Size the Yeast Cells with Starter figure goes up until I get to about 2.35 L where it hits 334.9 Billion and stays there no matter how much bigger I make the volume.

If I am correct,this value is 5x or 6x that of your estimate of viable yeast cells for your yeast package.  I can't remember which it is, but for a 24 hour starter, it is the theoretical maximum of cell replications which can be achieved before the yeast cells extend their cell walls too much and cause issues with their ability to bud.
 
That's what I was thinking was happening. Thanks.
 
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