Boil down question

[sharkuttack]

the recipe i am making calls for a 60 min boil, it is to yield a 5 gallons.

my question is after extracting my wert from the grains i end up with 6.5 gallons, so therefore i need to boil this down to 5 gallons, at what point should i start my sixty minute timer for the boil? should i wait till its at 5 gallons or should i just start timing it right away and if it gets boiled down to 5 gallons before 60 min, i will continue to boil till i reach 60 min. also should i add my hops and continue as normal during this 60 min boil?

your advice is apreciated.

 

[Hammy71]

Every system is a little diffferent. You want to extract enough runnings from your mash so that after boiling you have 5 gallons. It really depends on how much you boil off an hour. (If you don't know do a dry run with just water). I burn off 2.22 gallons an hour. Therefore I start my 60 minute boil with 7.22 gallons. Once the boil starts....your timer starts. Add the 60 minute hops at boil start. If you burn off one gallon/hour you only need to get 6 gallons from your mashing process. Make the wort volume match your boil off, not the other way around.

 

[BendBrewer]

When I see "Yields 5 Gallons" I think of 5.25 gallons into the fermenter.

What you need to know is your boil off rate. Using your pot, boil 5 gallons (average boil volume) for 15 minutes. Measure what you have left and multiply the difference by 4 to get a good idea of how much you will boil off in an hour. That amount + 5.25 gallons is what you should start with.

 

[Golddiggie]

In my setup, I boil off roughly 1 gallon per hour... I keep the boil right around 212F, so it's not as hard a boil as some may do. If you boil at 212-214F you should only lose about one gallon in the hour. If you boil at a higher temp, then you'll lose more per hour.

As mentioned already, it's good to test your setup before you go to brew. I would also invest in a good thermometer so that you can tell (via temp, not looks) when you've hit boil.

It's also a good idea to have a way to measure how much is inside your pot, at any time. That's good for when you're getting up to a boil, as well as when you're getting close to the finish. That way, you know when you're about to hit your target. It will also tell you if you have more in the pot than you had counted on, adjusting your boil time/speed accordingly.

 

[Frodo]

My boil off rate is usually around 1.5 to 2 gallons per hour, and seems to depend on the weather - if it's low humidity without wind I boil off a bit more than 2 gallons/hour. If the wind is blowing my flame and the boil isn't as vigorous closer to 1.5 gal/hr. And I usually plan my post-boil amount to be 6 gallons, so I can transfer 5.5 to the carboy after losing 1/2 gallon of wort to kettle trub.

 

[sharkuttack]

I appreciate the quick replys guys, i understand now its a matter of calculating grain absorbtion and my setups boil off rate to end up with 5 gallons at the end of my 60 min boil. i guess if im alittle under 5 gallons at the end of my 60 min boil i could always add a little water before cool off.

 

[Yooper]

In my setup, I boil off roughly 1 gallon per hour... I keep the boil right around 212F, so it's not as hard a boil as some may do. If you boil at 212-214F you should only lose about one gallon in the hour. If you boil at a higher temp, then you'll lose more per hour.

As mentioned already, it's good to test your setup before you go to brew. I would also invest in a good thermometer so that you can tell (via temp, not looks) when you've hit boil.

It's also a good idea to have a way to measure how much is inside your pot, at any time. That's good for when you're getting up to a boil, as well as when you're getting close to the finish. That way, you know when you're about to hit your target. It will also tell you if you have more in the pot than you had counted on, adjusting your boil time/speed accordingly.

I can't boil higher than 209 degrees where I live. No matter what, wort won't go higher. I'm surprised you can boil at a higher temp than 212.

Anyway, I boil off about 1.50 gallons an hour with my system. When I had my "old" system on the stovetop it was far less. What we're all saying is to boil hard enough to get a rolling boil, but no need to get the kettle rocking! If you start with 6 gallons, and boil down too much, you can always add a little water if you need to to hit your OG. It's easier to do that than to end up with too much wort the first few times!

 

[Golddiggie]

I appreciate the quick replys guys, i understand now its a matter of calculating grain absorbtion and my setups boil off rate to end up with 5 gallons at the end of my 60 min boil. i guess if im alittle under 5 gallons at the end of my 60 min boil i could always add a little water before cool off.

If you're only off by a little, I'd just leave it alone and just have less to ferment.

Yooper, On the stove top, at the altitude I'm at (close enough to sea level that boil is 212F), I can boil and then go past 212F depending on the amount I'm boiling. I've had water hit over 220F during a boil, when keeping the gas on... This is on the stove top too...

I plan to wrap my boil pot in some reflective insulation to help keep some of the heat in, to get improve the time it takes to get to a boil, as well as retain the heat.

Of course, I expect the boil off rate to change when I brew outside, but that's a few months off still... I need to get a burner and such before I can even think about that...

 

[BendBrewer]

I've had water hit over 220F during a boil, when keeping the gas on... This is on the stove top too...

You need to calibrate your thermometer. Plain water will not boil hotter than 212. PERIOD.

 

[Yooper]

You need to calibrate your thermometer. Plain water will not boil hotter than 212. PERIOD.

That was my point. Even at sea level, boiling water will never get above 212. Ever. If you're getting 220, the thermometer is bad or touching the bottom of the pot.

Anyway, we dragged this subject off-topic enough. Sorry to the OP!

 

[sharkuttack]

well my electric stove sucks, did a test, only boils off a 1/3 gallon an hour. i better be more precise extracting my wert, i dont wanna boil down all day!

 

[Yooper]

well my electric stove sucks, did a test, only boils off a 1/3 gallon an hour. i better be more precise extracting my wert, i dont wanna boil down all day!

Well, if you start with 5.5-5.75 gallons, you should be alright. Your electric stove is better than most, if you can actually boil that much! Many people say their electric stove can only boil 3 gallons!

 

[sharkuttack]

yeah id say it will only boil 3 gallons in my 5 gal kettle, im gonna put the rest in a second kettle