The rate constant k, from a variety's six-month loss.
This is first-order decay fitted to one endpoint. If a fraction L is gone
after 180 days at the reference temperature with no packaging, then
1 − L= e^(−k · 180) ⟹ k =ln(1/ (1 − L)) /180
Garetz publishes this as a lookup table (his Table II). The formula
reproduces it: 50 % lost gives 0.003851, and the table says 0.00385.
Parameters
alphaLostSixMonths: number
Fraction, not percent. Clamped to 0.99. A
variety that lost all its alpha in six months would need an infinite rate,
and we'd rather return a very fast curve than let Infinity reach a
recipe's IBU.
The rate constant
k, from a variety's six-month loss.This is first-order decay fitted to one endpoint. If a fraction
Lis gone after 180 days at the reference temperature with no packaging, thenGaretz publishes this as a lookup table (his Table II). The formula reproduces it: 50 % lost gives 0.003851, and the table says 0.00385.