Hey everyone!
I'm trying to pin down a variable in my BIAB brewing. I've done 4 batches so far, and had a similar issue with each: at mashout, with the proper amount of water, my gravity works out as such that I should hit my FG pretty much dead on, using the GU formulas given in Designing Great Beers. At the end of the boil, I'm left with exactly the amount of wort I expected, +/- a quart, but my gravity tends to be 10 points or so above what I was expecting. I had done the recipes in BeerTools using 75% efficiency the first few times, which I figured had caused the variance, as I am actually hitting closer to 81% brewhouse efficiency. However, changing my efficiency in BT even to 85% still doesn't account for a 10 point gain in FG. For specificity's sake, here's some specifics: last night I did an Irish Red with 3.5lbs MO, 2lbs Vienna, .2lbs C120L and .1lbs Roasted Barley. My final volume was 3.05 gallons, and my FG was 1.066. Mashed at 150f for an hour, mashed out at 170f for 15 minutes.
Would a wonky thermometer reading too low cause this -- that is, I know that mashing too high leaves you with too much unfermentable sugar; does that also bump the FG higher than expected, or does that variance not show itself until fermentation begins?
I'm trying to pin down a variable in my BIAB brewing. I've done 4 batches so far, and had a similar issue with each: at mashout, with the proper amount of water, my gravity works out as such that I should hit my FG pretty much dead on, using the GU formulas given in Designing Great Beers. At the end of the boil, I'm left with exactly the amount of wort I expected, +/- a quart, but my gravity tends to be 10 points or so above what I was expecting. I had done the recipes in BeerTools using 75% efficiency the first few times, which I figured had caused the variance, as I am actually hitting closer to 81% brewhouse efficiency. However, changing my efficiency in BT even to 85% still doesn't account for a 10 point gain in FG. For specificity's sake, here's some specifics: last night I did an Irish Red with 3.5lbs MO, 2lbs Vienna, .2lbs C120L and .1lbs Roasted Barley. My final volume was 3.05 gallons, and my FG was 1.066. Mashed at 150f for an hour, mashed out at 170f for 15 minutes.
Would a wonky thermometer reading too low cause this -- that is, I know that mashing too high leaves you with too much unfermentable sugar; does that also bump the FG higher than expected, or does that variance not show itself until fermentation begins?