2.5 Gallon Question

sp1365 · Sep 4, 2009

I am going to be starting out soon and due to various circumstances I will only be doing 2.5 gallon brews. I should be getting all my supplies to brew by the 20th, but I have a question before I get started. I plan on doing full boil, but how much water should I start with due to evaporation and my extract additions?

Revvy · Sep 4, 2009

sp1365 said:
I am going to be starting out soon and due to various circumstances I will only be doing 2.5 gallon brews. I should be getting all my supplies to brew by the 20th, but I have a question before I get started. I plan on doing full boil, but how much water should I start with due to evaporation and my extract additions?

It is really going to come down to the boil off rate of your stove....Take a pot of 3.5 gallons of water and time how long it takes to boil it down to 5...or boil for an hour and then measure the volume after....

Either way it will give you an idea of how much more water you will need to boiloff ....

humann_brewing · Sep 4, 2009

There is a lot of variables to determine the exact amount such as kettle size, diameter, temperature, humidity etc... The best thing is to just experiment and keep in mind that if you are doing extract, your extract will also add volume. So if you used 2.5 gallons to boil with and added the extract to that, you may have 2.7 gallons for example.

Typical evaporation pencentages are anywhere from 9-25% per hour but I think most people are in the low teens somewhere. You may also want to account for any liquid loss due to hops and anything else you use that may soak up the wort.

I think a good starting point to try and end with 2.5 gallons in bottles/keg you may use 3 gallons of water, add extract which will bring it up a bit 3.2 maybe, get say 2.7.-2.8 into the fermentor and bottle 2.5.

sp1365 · Sep 4, 2009

Thanks. That was where I was looking at starting, but I wanted to see if anyone else had some experience with it. Now begins the waiting game for my equipment to arrive.

HotbreakHotel · Sep 4, 2009

It'll take some practice on your equipment to nail it every time. Until then it doesn't have to be perfect to come out good.

If you boil off more than you thought you can always top off with water.

If you think you haven't boiled off enough, before your late hop additions you can decide to boil longer -- this will increase bitterness a little but not much, and increase the maltiness a little.

If you have graduation marks in your pot that helps, or you can make a dipstick. I used a wood dowel. I poured a measured gallon of water into my pot and made a mark on my stick, then another gallon, then another mark, etc. You could do it in half gallon or quart increments or whatever. Just remember that boiling wort takes up a little more volume than room temperature. According to beersmith, it would be .09 gallon for 3 gallons and .08 for 2.5 gallons, so just a little difference. I measure sometimes during the boil -- I just stop the flame for a few seconds so the bubbling stops.