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Old 12-18-2012, 02:22 PM   #1
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Default Boil-off

Good morning everyone,

Is there a reason I should boil without a lid? I add additional water to compinsate for the loss but would like to stop it.. When I do a 10 gallon batch, I add an extra gallon for this purpose but does it help in some way?

The only thing I can think is that it could serve to concintrate the wort a bit..



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Old 12-18-2012, 02:25 PM   #2
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Boiling without a lid allows you to get rid of DMS which can cause some off flavors

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Old 12-18-2012, 02:43 PM   #3
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Pecafaced hit it on the head. It sounds like you stumbled across the technique most all-grain brewers (and pro for that matter) use in that water usage is calculated with a boil-off amount counted in. The amount of water in the boil affects the concentration of the wort and thus hop utilization. You can top-off with sanitized water after the boil, but you (technically) would need to adjust your recipe if you were trying to hit particular numbers or replicate a beer. Why not just add extra water in the beginning and let it be sanitized with the rest of the wort? More volume lengthens your cooling time, but not by that much when you're talking about 10% volume change in most cases in AG. Extract brewers usually experience a 60% increase in post-boil and fermentation volumes (3 gal + 2 gal = 5 gal) and this defintiely affects recipe formulation and cooling time. So much to consider! Don't sweat it. Take good readings everytime you brew and you'll settle into a pattern. And, if you like your beer, RDWHAHB


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Old 12-18-2012, 03:06 PM   #4
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Yep, you want to boil without a lid. Otherwise, you run risks of DMS in your beer, whicih gives you canned corn/canned veggie taste.

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Old 12-18-2012, 05:09 PM   #5
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Yup, you always want to boil without a lid, and should be starting with more liquid than you need to go into the fermentor. Boiloff rate is usually between 10 and 15% per hour, but will vary with your vessel.


I can't be arsed to keep up this list of what's in the fermenters, but hey, check out the cool brewery I own! .. ..

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