Last year when I brewed an imperial stout my efficiency dropped to 53%. I’m about to brew the same beer and I was wondering if there was a way to predict this change in efficiency?
I am crushing my own grain this time and get around 72% with a 1.063 gravity beer. If I’m shooting for 1.100 is there a formula I can use to estimate the lower gravity?
I am making this with first runnings if that makes any difference.
First runnings partigyle around 53% sounds pretty close to what I get and my ‘normal’ no-sparge efficiency is around 68% (brewhouse). I think you get pretty close to the same efficiency if you calculate the whole (first and second runnings - or entire) recipe.
so if you are planning 5.5 gallons RIS and 5.5 gallons brown ale or porter calculate the recipe as 11 gallons of middling gravity ale. Say 1st beer is 1.100 and second beer is 1.040 calculate at 11 gallons of 1.070ish.
alternately you can download Sean Terrill’s batch sparge simulator or the BT partigyle tables and mess around till you figure it out.
Cool thanks.
I realized later that I messed up the calculations even more by cold steeping the dark grains and adding them in near the end of the boil. I never measured the gravity of what I cold steeped so my OG was off from that as well. Beer rocked though!
I think you mean Kai’s. That would definitely be my suggestion. If you’re only using the first runnings estimating gravity becomes pretty simple.
http://braukaiser.com/wiki/index.php?title=Batch_Sparge_and_Party_Gyle_Simulator
I could have sworn I had one of yours. Huh, there I go misattributing things again.
It’s possible. I put one together but stopped sharing it years ago because Kai’s was so much better. I didn’t realize there were still any copies “in the wild”.
Well it’s spiffy all the same. Thanks for the link!
well after closer examination it apears to be Kai’s after all. Sorry Kai.