Full or Partial Boil

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Tonedef131

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The only disadvantage of a full boil is that you need a wort chiller to cool it down. Since you already have the pot for a full boil I highly recommend doing one so long as you can cool down a full volume of wort. With a partial you can add cool water to chill it, this isn't an option with a full boil.

I firmly believe that your beer will always be better with a full boil. You will get less carmalization, better hop utilization, and it will be mixed together much better.
 

Rezilynt

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IMO, I would do a partial for your first time. You will not need to worry about the following;
Boilover, hops utilization (full boils usually need around 25% less hops). Also, you will have a much easier time getting the wort temp down quickly.
 
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LooyvilleLarry

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I have a DIY counter flow wort chiller that I built this last weekend, but am a little concerned about pouring that big pot through that tiny opening LOL (just kidding)...
 

Rezilynt

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I have a DIY counter flow wort chiller that I built this last weekend, but am a little concerned about pouring that big pot through that tiny opening LOL (just kidding)...
In that case, go for the full boil. Just make sure you watch it closely. Especially after adding LME and hops. Keep a spray bottle with water handy (helps stop the boilover). I also have a 30qt Start with 6 gal (I lose about 1.25 gals)
 

BarleyWater

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IMO, I would do a partial for your first time. You will not need to worry about the following;
Boilover, hops utilization (full boils usually need around 25% less hops). Also, you will have a much easier time getting the wort temp down quickly.
It's actually a MUCH larger difference than that...

The maximum threshold of IBUs in any given batch of beer is 100, anything over that is only adding to flavor (and head retention and mouthfeel). This maximum number is also only in worts of around 1.050. Now if you are boiling 3 gal down to about 2.5, and adding 2.5 gal of wort, then your maximum is already sliced down to 50 IBUs in a batch, and that is still with a wort gravity of 1.050 or below.

Now, with a full boil if you are trying to reach a final gravity 1.050, then you will have near 100% efficiency when it come to alpha acid isomerization and IBU absorption, and you can reach the 100 IBU mark, since you would be starting the boil around 1.044 and boiling down to your OG. When using LME, this will be about 7 lbs. If you put 7 lbs of LME into only 3 gallons of wort, then you are starting with a pre boil gravity of 1.084, boiling down to probably around 2.5gal at 1.100 before topping of with water to reach your OG of 1.050. Far above the ideal IBU efficiency gravity. This will leave you with a wort that has a max IBU rating of approx. 82.7, not too bad, but wait. After topping off, you will have only 41.4 IBUs.

So without doing a full boil, your maximum IBU level would be 41.4, not quite the hop bomb you may have thought you were making.
 

Slappy White

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I've found that I get a certain off-flavor when I do partial boils with extract. When I have done full boils with similar recipes, the off-flavor is not there. I have heard ppl call this extract 'twang' and is just another reason to do a full boil.
 
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LooyvilleLarry

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It's actually a MUCH larger difference than that...
So without doing a full boil, your maximum IBU level would be 41.4, not quite the hop bomb you may have thought you were making.
:confused: So, do the full boil with the full hops in the kit?
 

Yooper

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Yes i was wondering the same thing, as I am about to do my first full volume boil...
You could tell us the recipe, and we can run it through some brewing software for you. Usually it's fine, but I had one recipe with very low IBUs (like 15) and when I did a full boil with it for the first time, it tasted twice as bitter to me. Sure enough, when I ran it through Beersmith, the IBUs were around 30! That's not usually the case, but we'd be happy to check for you.
 

profarm

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You could tell us the recipe, and we can run it through some brewing software for you. Usually it's fine, but I had one recipe with very low IBUs (like 15) and when I did a full boil with it for the first time, it tasted twice as bitter to me. Sure enough, when I ran it through Beersmith, the IBUs were around 30! That's not usually the case, but we'd be happy to check for you.
Oh yeah, its a Northern Brewer Nut Brown...Thanks

Nut Brown Ale Extract Kit -- Kit Inventory Sheet
 

Yooper

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I assumed the hops were 6.2% AAU, since that's what I have in my computer.

With a full boil, the IBUs are 22.8. The IBU/SG ratio is .492

With a 2.5 gallon boil, the IBUs are 13.4 with an IBU/Sg ratio of .288

If the recipe suggest a 2.5 gallon boil, and you want to do a full boil, you'd want to reduce the hops to .60 ounces if you want to "match" the recipe.
 

profarm

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Thank you so much!! I am new to the site and it IS GREAT! I all ready have EdWorts Apfelwein going right now...Thanks again
 

Ecnerwal

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Mind that I don't have quite the vigorous burner some folks do (I use a 2600W canning element on an electric stove with a 40 qt pot) but boilovers need not be much of a concern. Rather than damp them down, I just use my big spoon to skim the foam off, thus removing some of the hot break proteins. Does not take much - usually less than 5 minutes of skimming before it's on to worry-free boiling. If using a honking gas burner, you could wind it up to get near boiling, slow it down a mite to get the hot break at boil, and then wind it up once the foam is cleared off.
 

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Great info everyone! This is very useful to me as well as I'm hoping to soon be trying full boil extracts along my way to that first all-grain batch.
Well, that's how the addiction starts. Start with partial boil extracts, then pretty soon getting ready to try all-grain.

Are you thinking of kegging yet? :D

Seriously, one item that REALLY helps is some brewing software. They all (I think) have free trials, and can help with the hopping as you scale up to full boils, as well as helping to estimate final gravity and see the differences with late extract additions and hops utilization. It's also a nice place to save your recipes that you want to do "someday". I think Beersmith was $20, and I've been very happy with it.
 
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