I need to figure out what is going on. I hit my numbers consistently with average gravity beers. But every time I attempt a big beer I miss my numbers - sometimes by a lot.
Today I brewed a RIS which was supposed to be 1.092 OG. I took a pre-boil gravity and it showed 10 points lower than predicted so I added all the DME I had (about 13 oz.). Even with that the OG is sitting at 1.077!
The grain crush was good. Brun’water predicted a pH of 5.5. My temperature held steady in the mash at ~155*. It was an hour mash. I planned a 90 minute mash but was running short on time so I kept it to an hour.
I’m at a loss. Any ideas?
The good news is that even when I miss my OG the beer still tastes good.
Was your final volume a little higher than expected ? The DME should have made up most of that deficit, assuming 5 gallons. Could your FG reading have been stratified? I know it’s easy to get a stratified reading after cooling to pitch temps.
I take the sample from the hoses that go from the BK to the fermenter. So it has a lot of trub in it. The wort is not yet to pitching temp. I may take another sample once it gets there.
My efficiency goes down with really big beers as one would expect.
The one I made that was at 1.115, it was a batch sparge, I ran some 1.040ish wort into a 10 gallon kettle I have, then boiled it hard until it was over target, added into the main batch. No small beer on that batch.
It is something you will learn as you brew on your system. I get about 60-63% on beers 10% and over. One thing you can do is sparge more and boil for 120 minutes. I do this frequently and it helps a bit.
