smizak
Well-Known Member
I just figured out an efficiency issue I was having, and didn't see my particular problem ever discussed on this forum.
Ever since going all-grain, I noticed that I would "lose" about 3-4% efficiency from pre-boil gravity readings to fermenter readings. I brew 6 gallon batches and boil down from about 7.5 gallons. It happened again this sunday. A little over 7 gals. in the kettle read 1.052 which gave me 84% extract efficiency. Boiled down to 6 gals and cooled read 1.061 which gave me 80%. It was driving me nuts, because I know the sugar didn't freakin evaporate, and I don't add any additional water to dilute wort.
What never occurred to me was that when pulling my sample from the kettle, the wort was near boiling, around 190-200F. Accounting for the thermal expansion, my 7.1 gals of 200F wort was actually around 6.8 or so gals. of 60F wort. This accounts perfectly for the missing efficiency points.
Anyway, thanks for reading about me understanding brewhouse efficiency better, and I hope this helps someone else somehow.
Ever since going all-grain, I noticed that I would "lose" about 3-4% efficiency from pre-boil gravity readings to fermenter readings. I brew 6 gallon batches and boil down from about 7.5 gallons. It happened again this sunday. A little over 7 gals. in the kettle read 1.052 which gave me 84% extract efficiency. Boiled down to 6 gals and cooled read 1.061 which gave me 80%. It was driving me nuts, because I know the sugar didn't freakin evaporate, and I don't add any additional water to dilute wort.
What never occurred to me was that when pulling my sample from the kettle, the wort was near boiling, around 190-200F. Accounting for the thermal expansion, my 7.1 gals of 200F wort was actually around 6.8 or so gals. of 60F wort. This accounts perfectly for the missing efficiency points.
Anyway, thanks for reading about me understanding brewhouse efficiency better, and I hope this helps someone else somehow.