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Old 01-23-2011, 03:27 AM   #1
winvarin
 
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I hate to even ask this. I should know better as long as I have been brewing. But I am drawing a blank on what I should expect in missing my boil off and consequently my gravity target.

Brewed an oatmeal stout today. 15lb grain bill (9.75 maris otter; 1.75 lb flaked oat; 1 lb. carapils; .75 lb each of Chocolate and victory; .5 lb each of 80L crystal and roasted barley)

Bill was shooting for 6 gallons in the kettle at the end of the boil, 5.5 to the fermenter.

I boiled a little more vigorously than I had planned and wound up with 5 gallons even going into the fermenter. I chose not to top up the extra half gallon. At my usual brewhouse efficiency, the recipe calculator estimated a gravity of 1.058 with 5.5 gal to the fermenter.

I wound up with 5 gal of 1.063, or 64 (there were a lot of bubbles clinging to the hydrometer and I wasn't wearing my glasses.

It's possible that I could have gotten better efficiency. I am chalking it up to the boil off though. My questions are these:

Considering my grain bill, I knew I was going to have a lot of unfermentables (mashed at 154.5F, dropped to 153F by the time I started sparging). I got dinged for body on the last iteration of this beer. What should I expect here? Is the beer going to be stronger because of the additional gravity points? Or should I just expect for attenuation to be what it is and I will wind up with a fuller bodied beer?

Like I said, I feel like such a newbie for even asking. But I've been brewing the last several hours and my brain is having trouble wrapping my head around what to be looking for.

Temperature is reliable. I measured with a brand new, calibrated, just out of the packaging Thermapen.

 
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Old 01-23-2011, 06:00 AM   #2
JuanMoore
 
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6 gal of 1.058 concentrated to 5.5 gal would end up about 1.063, so you probably got your usual efficiency and just boiled off more. The attenuation will likely be about the same, but since there are more of both fermentable and unfermentable sugars, it will be both stronger and have more body, not one or the other.

 
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Old 01-23-2011, 03:12 PM   #3
winvarin
 
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Thanks JuanMoore. That's exactly what I was looking for. Glad I didn't top off then,

The last version of this beer was made with about 1.75# less grain (no carapils, .5# less maris otter and .25# less oats) and came to 1.053 at 5.5 gallons. The flavor was awesome but it finished a little thinner than I would have liked. I was trying to make this version beefier across the board.

Looks like I am on track for that.

 
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