Boil-Off And Dilution

Boil-Off And Dilution

For determining gravity or wort volume after removal or addition of water
Any Volume Unit, But Remain Consistent (Litres, US Gallons, Imperial Gallons, Etc.)
X.XXX
oP
Same Volume Units As Used Above (Litres, US Gallons, Imperial Gallons, Etc.)
SG
oP
SG
oP
Any Volume Unit, But Remain Consistent (Litres, US Gallons, Imperial Gallons, Etc.)
X.XXX
oP
X.XXX
oP
Same Volume Units As Used Above (Litres, US Gallons, Imperial Gallons, Etc.)
Same Volume Units As Used Above (Litres, US Gallons, Imperial Gallons, Etc.)
Daniels, Ray (1998). Designing Great Beers: The Ultimate Guide to Brewing Classic Beer Styles (Illustrated Edition). Boulder, Colo.: Brewers Publications
Noonan, Gregory J. (1996). New brewing lager beer : the most comprehensive book for home- and microbrewers (Completely rev. and expanded ed.). Boulder, Colo.: Brewers Publications.

Hitting Target Original Gravity

Hitting target Original Gravity (OG) and target volume on brew day can often be a challenge. Some of the reasons why targets are not hit could be:

  • Poor Conversion Efficiency (more on that here)
  • Poor lautering/sparging efficiency
  • Variable or unknown boil-off rate
  • Uncalibrated refractometer
  • Spills

During the boil, adjustments can be made by adding water to increase wort volume and lower gravity, or boiling longer to decrease wort volume and raise gravity. This calculator can help you hit your target gravity by calculating the amount of boil-off or dilution required to hit the gravity target.

Boiling Wort
Boiling Wort

Cautions On Adding Water Or Boiling Longer

When adding water during a boil (or any other time), make sure the water is good quality and is sufficiently free from Chlorine.

When boiling longer, be sure to adjust the timing of your late hop additions according to the revised end of the boil. Also, be careful of scorching during extended boils if there’s a potential of this happening with your set-up.

Boil-Off And Dilution
Boil-Off And Dilution