Originally Posted by broadbill
Did you pull the sample from the bottom?
Boy, I can't see stirring being an issue here, I would think that combining runnings (however you do it) would mix it up pretty good....
How did you calculate efficiency?
It happens. I used to see this sort of stratification in my boil pot. I also would have thought that they would mix better.
Though, I think a lot of the wild efficiency stories are just due to measuring the volumes wrong, or measuring the wrong things altogether.
I think it's possible to get better than 100% in a lab setting, where extraction of sugars doesn't rely on mashing, but instead on some other method. I read that somewhere.