Braukaiser's ceiling on growth from a stirred starter: 1.4 billion new cells
per gram of extract.
The model is published as pseudo-code in Kai Troester, Estimating yeast
growth, Braukaiser, 3 November 2012,
http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/, and
it consists of these four constants. He plots growth rate (new cells per
gram of dry extract) against inoculation rate (cells pitched per gram of
that extract). Below GROWTH_PLATEAU_INOCULATION_RATE the measured
growth rate is flat at 1.4 B/g, so a lightly pitched stirred starter makes
as much yeast as the extract can support, and pitching it thinner doesn't
get you more.
This is why the model is useful: counting cells out of a stir-plate
starter, Kai got substantially more yeast than Mr Malty's older model
predicts, and got the same answer when he repeated the experiment.
Braukaiser's ceiling on growth from a stirred starter: 1.4 billion new cells per gram of extract.
The model is published as pseudo-code in Kai Troester, Estimating yeast growth, Braukaiser, 3 November 2012, http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/, and it consists of these four constants. He plots growth rate (new cells per gram of dry extract) against inoculation rate (cells pitched per gram of that extract). Below GROWTH_PLATEAU_INOCULATION_RATE the measured growth rate is flat at 1.4 B/g, so a lightly pitched stirred starter makes as much yeast as the extract can support, and pitching it thinner doesn't get you more.
This is why the model is useful: counting cells out of a stir-plate starter, Kai got substantially more yeast than Mr Malty's older model predicts, and got the same answer when he repeated the experiment.
It only applies to stirred starters under foil. His NHC 2013 talk says so ("For foil capped stirred starters only"), https://braukaiser.com/documents/Troester_NHC_2013_Step_Up_Your_Starter.pdf. See UNSTIRRED_GROWTH_PER_GRAM for the rest.