Post boil gravity calculation

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MattGuk
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Post boil gravity calculation

Post by MattGuk » Sat May 29, 2021 9:32 am

Hi everyone, just a quick one.
I recently brewed an English Golden Ale and the Brew went really well.
I did have one slight issue however, my pre boil gravity was 1.046 @ 31 liters and I ended up with 1.046 @ 27 liters post boil.
Now I know this is wrong and I guess my wort wasn't mixed well before I took the reading.
I know there is a calculation which will help me figure out my approximate gravity with the boil off, but I'm not sure what it is.
Could somebody please tell me the calculation if you know?

Thanks guys

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Eric
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Re: Post boil gravity calculation

Post by Eric » Sat May 29, 2021 2:13 pm

V1 X G1 = V2 X G2 where V1 is pre-boil volume and G1 is pre-boil gravity. V2 and G2 are post-boil measurements.
Without patience, life becomes difficult and the sooner it's finished, the better.

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vacant
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Re: Post boil gravity calculation

Post by vacant » Sat May 29, 2021 3:18 pm

Try this link

guypettigrew
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Re: Post boil gravity calculation

Post by guypettigrew » Sat May 29, 2021 3:29 pm

Eric wrote:
Sat May 29, 2021 2:13 pm
V1 X G1 = V2 X G2 where V1 is pre-boil volume and G1 is pre-boil gravity. V2 and G2 are post-boil measurements.
Absolutely, just one thing. G1 & G2 are just the last two figures of the gravity. ie A gravity of 1.046 in 20 litres-->46 * 20 = 920.

But I'm sure you realised that.

Guy

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