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11-22-2010, 07:07 PM   #1
steve25
Recipes

Jan 2010
michigan
Posts: 24

how much higher will o.g. be after boil, compared to out of mash tun?

11-22-2010, 07:12 PM   #2
Walker
I use secondaries. :p

Recipes

Sep 2005
Cary, NC
Posts: 10,987
Liked 101 Times on 89 Posts

Quote:
 Originally Posted by steve25 how much higher will o.g. be after boil, compared to out of mash tun?
it depends on how much volume you have before and after the boil.

example:

if you measure 1.040 gravity in 7 gallons of wort in the kettle, your wort contains a total of:

40 * 7 = 280

gravity points.

If you boil this down to 5 gallons, those 280 points will be spread out in 5 gallons, so the gravity after the boil will be:

280 / 5 = 56

Leaving you with 1.056 gravity on the 5 gallons.
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Ground Fault Brewing Co.

11-22-2010, 07:50 PM   #3
devilishprune
Recipes

Mar 2010
Posts: 1,241
Liked 10 Times on 10 Posts

C1V1=C2V2 is a brewer's best friend.

C1=(gravity)-1 preboil and V1 is preboil volume.

C2=(gravity)-1 postboil and V2 is postboil volume.