I brewed an ESB on Saturday and something I can't explain happened:
I took the preboil gravity and it came out at 1.049 (chilled to 60). After boiling and chilling, I took the OG sample, chilled to 60, and it came out...1.051?!? I had 6.75g. preboil and minus trub/hop absorption I ended up with UNDER 5g in the FV yet my gravity only went up 2 points?!?
The samples were taken as follows:
preboil, I cracked the BK valve and ran some wort from the kettle (all runnings collected and boil almost going) into the test jar, cooled in bucket of ice water.
postboil, I pinched tube about halfway thru racking into FV and filled test jar, cooled in bucket of ice water.
Any possible explanation??