3 gallon batch boil-off

[ZenDrinking]

I'm relatively new to brewing. I have brewed a one gallon batch which seems to have turned out okay. It's bottle conditioning now. I was disappointed by the small yield that I got from it so I'll probably moving up soon. I have limited space and only enough room for a 3 gallon carboy.

My question is if I'm going to convert 5g recipes to 3 gallons what volume of water should I start with? The recipes I've read for 5g say to boil 2.5g so I'm assuming with 3g I'd start with 1.5g. However, if I was only left with ~1g of wort and mixed that with water in the fermenter wouldn't that have an effect on gravity? Is it normal when brewing 5g partial boils to only be left with 1.5-2g?

I believe my pot boiled off about .5g in 45 min when making my one gallon batch (started with 1.25 per instructions.)

 

[hannibalmdq]

I'm relatively new to brewing. I have brewed a one gallon batch which seems to have turned out okay. It's bottle conditioning now. I was disappointed by the small yield that I got from it so I'll probably moving up soon. I have limited space and only enough room for a 3 gallon carboy.

My question is if I'm going to convert 5g recipes to 3 gallons what volume of water should I start with? The recipes I've read for 5g say to boil 2.5g so I'm assuming with 3g I'd start with 1.5g. However, if I was only left with ~1g of wort and mixed that with water in the fermenter wouldn't that have an effect on gravity? Is it normal when brewing 5g partial boils to only be left with 1.5-2g?

I believe my pot boiled off about .5g in 45 min when making my one gallon batch (started with 1.25 per instructions.)

You'll just need to run some tests. I brew in 3 gallon carboys. I find that for my system I need to end up with 3.75 gallons pre-boil to come in at 3.1 gallons post-cooling on a 70 minute boil, and that can fit about 2.5 to 2.75 gallons in the carboy (fitting a blow off tube just in case).

That normally means that I'm using between 4.1 and 4.4 gallons of brewing water, depending on the grain bill and what method I'm using (BAIB, no-sparge, single batch, etc) and how long I'm boiling.

It took several batches to iron out my system. Take your best guess based on what you know so far and keep good notes. You'll have it tuned in soon enough.

 

[Yooper]

I'm relatively new to brewing. I have brewed a one gallon batch which seems to have turned out okay. It's bottle conditioning now. I was disappointed by the small yield that I got from it so I'll probably moving up soon. I have limited space and only enough room for a 3 gallon carboy.

My question is if I'm going to convert 5g recipes to 3 gallons what volume of water should I start with? The recipes I've read for 5g say to boil 2.5g so I'm assuming with 3g I'd start with 1.5g. However, if I was only left with ~1g of wort and mixed that with water in the fermenter wouldn't that have an effect on gravity? Is it normal when brewing 5g partial boils to only be left with 1.5-2g?

I believe my pot boiled off about .5g in 45 min when making my one gallon batch (started with 1.25 per instructions.)

If you are using the same pot you will boil off the same amount of liquid in the same amount of time. Boil as much as you can fit in your pot. Generally the more liquid boiled, the better the finished product.
The only reason to use a smaller amount of liquid is so that it fits in your pot. If you can boil 3 gallons, boil 3 gallons. If you can boil only two gallons, well then of course boil two.

 

[dkevinb]

If you have a 3 gallon carboy you probably don't want to put more than maybe 2.5 gallons in it. If you're doing extract or extract plus specialty grains I'd calculate the recipe for a 2.5 gallon batch and start with 3 gallons of water. That will be close to a full volume boil, which is ideally what you want to do, like Yooper said. If you fall short you can top off in the fermenter after chilling and transferring. That's assuming your kettle can boil 3 gallons of wort without boiling over. If you're kettle isn't that big boil as much as you can without boilover.

 

[ZenDrinking]

Currently I only have a 2 gallon kettle. Seems like I'll probably need to upgrade that when I get my carboy.