As I understand Tinseth's formula is derived from curve fitting (as I read it from his article).
However I can't see if he's using pellets or cones and I think that the utilization differs. I expect that eventually one would get the same utilization from hops and pellets so the difference in the formula should then be in the time constant in the time factor. That would lead to a formula like:
IBU = ... (1-exp(-kt))/4.15
Should one use different value for
k depending on if I use pellets or whole hops? Which one does the standard value of
k=0.04 applie? Or is there a different formula for the use of pellets or whole hops?