Hello. I am not quite sure this is the correct place for this question so I will apologize now if it isn't. As a home brewer I mash the malt with hot water and collect the runoff (called wort) which contains the sugars needed for fermentation. Most recipes call for a boil length of either 60 or 90 minutes with an anticipated specific gravity at the end of the boil. My question is this, if I know:(adsbygoogle = window.adsbygoogle || []).push({});

The volume of wort collected in gallons

The specific gravity of the wort before the boil

The anticipated specific gravity post boil

The temperature at which the wort boils, 212Â° F

An evaporation rate of 20% per hour

How long must the boil be to reach the anticipated specific gravity? I'm not too worried about humidity, ambient temperature, elevation, or other external factors, but knowing this could make planning a brew day much easier.

Thank You,

Tom Dible

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# How long to boil?

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