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5 gallon boil vs. 3 gallon boil

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Gtrman13

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Most recipes I see call for a five gallon boil, but my electric stove will barely boil 3 gallons. Is it a good idea to simply do a 3 gallon boil and then top it up to 5 gallons in the fermenter? I know some recipes call for this, but is it a good idea to do this for recipes that call for 5 gallon boils?
 
You have a choice.

You can scale your batches down to three gallons and do full boils.

You can do partial boils with all your gravity points for five gallons, but inside of three gallons of liquid and then top up at the end. People will say that hop utilization suffers from reduced boils. Also, the max number of IBU's in the finished product wil be limited.

If you want five gallon batches, then do the reduced boil.

About the max IBU's:

If 100 IBU's is the max you can get into solution, then 100IBU's in 3 gallons would work out to 60 IBU's as the max IBU's in 5 gallons. Are you doing a beer under 60 IBU's? Then no problem. Final IBU's = Stove volume in gallons /Fermenter volume in gallons * Stove IBU's
 
I used the equipment I had and could only do partial boils and I had to top up to my target volume in the fermenter. I never had any problems doing this.

I just recently did a full boil (meaning a 6.5 gallon boil) and I did not have to top up.

I've heard that the single best way to improve your beer IS a full boil. But- you work with what you have.
 
I would do a 3 gallon boil with a partial late extract addition (Add half of your extract at the beginning of the boil, and the other half with just a couple minutes left in the boil, just long enough to kill any bugs). This will help with hop utilization and wort darkening.

Top up to your full volume with cold water (I keep a couple of gallons of spring water in the fridge) to bring temps down rapidly, then chill the rest of the way with an ice bath or wort chiller. I don't know if pouring cold water into near boiling wort is a "bad idea", but I do it gently to avoid splashing, and it brings my temps down much faster and conserves ice since I don't have an immersion chiller. My feeling is that for any possible detriment, conversely there's the benefit that it will preserve flavor and aroma from late hop additions since it brings the temperature down to about 120 degrees F in less than 60 seconds.
 
+1 for the late extract addition. Did this a couple weeks ago and it seemed to work out pretty good.
 
I would do a 3 gallon boil with a partial late extract addition (Add half of your extract at the beginning of the boil, and the other half with just a couple minutes left in the boil, just long enough to kill any bugs). This will help with hop utilization and wort darkening.

Top up to your full volume with cold water (I keep a couple of gallons of spring water in the fridge) to bring temps down rapidly, then chill the rest of the way with an ice bath or wort chiller. I don't know if pouring cold water into near boiling wort is a "bad idea", but I do it gently to avoid splashing, and it brings my temps down much faster and conserves ice since I don't have an immersion chiller. My feeling is that for any possible detriment, conversely there's the benefit that it will preserve flavor and aroma from late hop additions since it brings the temperature down to about 120 degrees F in less than 60 seconds.

+1 on late extract. I've always the bulk of it in the last 15 minutes.

I wonder what size kettle the OP is using. I was never able to top up my boil kettle with cold water, it wouldn't have made much of a difference. I always cooled it in a cooler full of water, ice and salt. After about 20 minutes I racked it to a carboy/bucket, topped up with water to cool further and aerate.
 
Echoing posters above, it's preferable to do a full boil on a 5 gallon batch, but if you have to do a concentrated version you can compensate for hop extraction issues by increasing hop volume in recipes that call for a full wort boil.

FWIW I was having the same problem and stepped up to full volume boils and all-grain by picking up a 10 gallon Megapot from Northern Brewer - it has extra wide dimension to cover two burners on my stove (I have a gas stove, but don't see why you couldn't do the same thing with electric).
 
I do 3 gallon boils sometimes for AG brews, I just adjust my Beersmith recipe accordingly, and it does the calculations for me. I end up with 5-6 gallons in the end, depending on the recipe. I just top up with tap water - works awesome because my tap water is pretty much the best around. I wonder how many others do this? IE: if you need 7 lbs of grain for 5% abv in 5 gallons of beer, I only boil 3 gallons and my hop additions just need to be bigger for higher IBU beers due to reduced utilization. I also increase flavoring hop additions just because.

The max 100IBU in solution is news to me though. Does anyone have any sources for that?
 
I have the opposite problem - most recipes I see are for partial boils and I want to do 5 gallon boils. Where are you getting your recipes?
 
Apart from hop utilization and the unreliable SG reading (wort and top-off can take a long while to fully mix*), I don't see a reason why it would matter really. A lot of people do it all the time without any problem.

I don't get the argument that full boils make your beer in any way "better" unless you top off with something crazy like 3 gallons of unboiled water that tastes like ass. I'm not taking a pot-shot at you Lcasanova but this is something I have heard a lot and it probably stems from the fact that you need a lot of water from AG (strike+sparge) if you want to keep your efficiency up and people aossicate AG with better brews. Also, what is "better" anyway ? Mandatory secondary and not splashing wort to avoid hot side areation used to be "better" too.

Partial boils do limit the final ABV you can do since you can only fit so much grain/extract into 3 gallons. So you have to take this into consideration if you want to only brew 5,5 gallon batches of 11% ABV Trippel : full boil is not only better, it's a necessity.

* This means you can just take your SG when the wort is cool and calculate how diluted it will get with the right amount of water, instead of shooting for a specific batch size.
 
I have the opposite problem - most recipes I see are for partial boils and I want to do 5 gallon boils. Where are you getting your recipes?

Assuming you are talking to me, I make my own recipes usually. Or, if I want to try my first one of a style, I will take a tried and true recipe (IE O'Flannigan stout) and I will edit it to suit my tastes/yeast on hand/hops and grains on hand.

Its easy to take a partial boil and translate to a full boil, you just have to fiddle with beersmith. Watch your IBUs, OG/FG, etc and make sure they are as intended. I guess it takes some getting used it.
 
Apart from hop utilization and the unreliable SG reading (wort and top-off can take a long while to fully mix*), I don't see a reason why it would matter really. A lot of people do it all the time without any problem.

I don't get the argument that full boils make your beer in any way "better" unless you top off with something crazy like 3 gallons of unboiled water that tastes like ass. I'm not taking a pot-shot at you Lcasanova but this is something I have heard a lot and it probably stems from the fact that you need a lot of water from AG (strike+sparge) if you want to keep your efficiency up and people aossicate AG with better brews. Also, what is "better" anyway ? Mandatory secondary and not splashing wort to avoid hot side areation used to be "better" too.

Partial boils do limit the final ABV you can do since you can only fit so much grain/extract into 3 gallons. So you have to take this into consideration if you want to only brew 5,5 gallon batches of 11% ABV Trippel : full boil is not only better, it's a necessity.

* This means you can just take your SG when the wort is cool and calculate how diluted it will get with the right amount of water, instead of shooting for a specific batch size.

No problem man, that's what these forums are for right? I'm not saying I am an expert nor that I've tired this side by side but I have been told that a full boil is better. Here is a thread about full boils:

https://www.homebrewtalk.com/f37/if-full-boil-possible-do-89826/

And one about hop utilization in a full boil for the question earlier:

https://www.homebrewtalk.com/f39/full-boil-vs-partial-boil-hops-utilization-88417/
 
To the OP:

Do you live in a house or prehaps an apartment where you could use a turkey fryer and LP tank to do larger boils outside or in the garage. the house we moved into has an electric stove so it is evry hard to boil much more than 3 gallons. I went on craig's list and found a used LP turkey fryer for $30 (new ones at Menard's run about $60-80) and now I can do 6 gallon boils out in the garage with no problem.

Just FYI
 
I read the entire 16 pages and I cannot tell you why full boil is supposed to be better apart from "it has to do with that Maillard stuff" and it reduces caramelization :D I can see how you can scorch the bottom of the wort if you are doing ridiculously a small partial and adding all the extract at the beginning. The wort is simply too high gravity. But if you are boiling 4 gallons of a tame wort (1.05 for example) and topping off to get to 4 gallons of 3.5 % ABV afterwards, I fail to see how it could make much of difference. The concentrated wort gravity on this brew will be much lower than if you were doing a full boil on an old ale or dubbel, for example (unless you routinely boil-off 3-4 gallons on 5.5 gallons boils, but this applies more to all-grain).

It's just common sense that doing a 2.5 gallon boil and then adding 3 to 4 gallons to hit 5.5 is not the best option, especially if you are brewing something that has more than 4 or 5 % ABV. For once you still have to boil all that water to sterilize it (or buy RO or spring water) and you need to put a boatload of hops to get your bitterness.

But reading the thread, I might just try a split boil: 5 gallons pots are cheap and you only need two of those to split your full boil since you figure to lose a gallon or a gallon and a half in an hour. Might also make for faster boiling/cooling times than if using a single brew kettle.
 
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