Full Boil VS Partial Boil

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Dave77

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Is it better to boil a full 5 gallon wort, or boil 2.5 gallons and then top up with water?

The recipes seem to say 'full boil if you can, but half-boil-and-add-water is fine too'. Does it make much of a difference?

I do have a 7-gallon pot, so I can make it happen. Just wondering if it makes that much of a difference at the end of the day?
 
Well you will get beer either way but if you were doing an all grain full works I would do a full boil you want to make best use of your hops and also make a clear beer. The other aspect is that with a concentrated wort a boil over is more of a danger . You don't give many clues as to what you are make from what so answers are going to be a bit of a guess.
 
Just make sure you end up with the correct number of gallons.
In a full boil, I know every bad thing in the wort is killed off.
I don't know what might be in the top-up water when I do a partial boil, but I've some it a bunch of times without any issues.

Do what works best for you
 
Is it better to boil a full 5 gallon wort, or boil 2.5 gallons and then top up with water?
[...]
Just wondering if it makes that much of a difference at the end of the day?
I'll assume a wort made from DME/LME.

If you can do a full volume boil and can cool the wort in a timely manner, a full volume boil keeps it simple.

A partial boil (with late additions of DME/LME) is a solid approach for brewing 5 gal batches inside (on a stove top or using an induction cook top).

With a partial boil, the concerns are
  1. boiling a concentrated wort (boil at SG 120 for an SG 60 beer), and
  2. perceived limits on the bitterness that can be boiled into a volume of water.
The common approach for partial boils is to
  • use roughly half the water and half the DME/LME at the start of the boil,
  • add half the DME/LME around the end of the boil,
  • and 'top up' with water to assist in cooling the wort.
A detailed description of this approach (along with strengths and limitations) can be found in chapter 1 of How to Brew, 4e (Palmer, 2017). Other chapters in the book discuss how to approach high IBU recipes and why concentrated boils (e.g. boil a SG 120 wort to make an OG 60 beer) may not be desirable. The book Methods of Modern Homebrewing (Colby, 2017) has additional insights.
 
I might weight the answer more to if the burner can boil the full volume of wort at the level of boil you wish to have.

I'd rather have the control of how hard the boil is and have to do additions as opposed to just barely boiling.
 
Well you will get beer either way but if you were doing an all grain full works I would do a full boil you want to make best use of your hops and also make a clear beer. The other aspect is that with a concentrated wort a boil over is more of a danger . You don't give many clues as to what you are make from what so answers are going to be a bit of a guess.
Sorry, I'm new to homebrewing so I'm 'practising' with a Brewer's Best kit before graduating to a non-kit recipe. The one I am specifically asking about is an American Amber Ale, but all of their recipes seem to have the same instructions for the wort.

https://www.brewersbestkits.com/assets/1007_americanamber_recipe.pdf
I gather for a kit like this it doesn't really matter, but for an all-grain recipe it may be beneficial to do a full boil?
 
, but for an all-grain recipe it may be beneficial to do a full boil?
IMO, once you get to the boil, extract or all-grain is essentially the same. Though I might be wrong, I've never brewed with extract.

"Full volume" is a term you'll see all-grain brewer's tossing about for the mash step. Which isn't a boil and isn't something one doing all extract would do.

So your question about boil is more about equipment. Both for the volume it can hold or if it can boil that amount of wort properly. I started off with one gallon all-grain and could boil the full volume. When I increased to 2½ gallon recipes, then my equipment couldn't handle the full volume to be boiled so I added water to the more concentrated wort I made in stages as the water boiled off.

So it might be more that if your boil can't handle the full volume of wort whether by container size or ability to boil, then maybe you shouldn't do a full mash volume. Essentially just use less water for the mash step and add that water back in as you boil off water.
 
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Sorry, I'm new to homebrewing so I'm 'practising' with a Brewer's Best kit before graduating to a non-kit recipe. The one I am specifically asking about is an American Amber Ale, but all of their recipes seem to have the same instructions for the wort.

https://www.brewersbestkits.com/assets/1007_americanamber_recipe.pdf
I gather for a kit like this it doesn't really matter, but for an all-grain recipe it may be beneficial to do a full boil?

To be honest I would not worry one way or the other you will get drinkable beer if you pay attention to the sanitisation of everything. Back in the day home made beer was very often just ready hopped liquid malt extract, sugar and tap water fermented with a very basic yeast... people made it and drank it.
 
The one I am specifically asking about is an American Amber Ale, but all of their recipes seem to have the same instructions for the wort.
From the kit:
1679157558060.png

With a standard strength beer and low IBUs, a partial boil with late DME/LME additions will work. Add all the hops at the start of the boil.
 
I just looked at your instructions. I'd just reduce the water and add it as needed to the boil.

Note, the forum software had a glitch. Read the full reply down below in #12
 
IMO, once you get to the boil, extract or all-grain is essentially the same. Though I might be wrong, I've never brewed with extract.

The carbohydrates, proteins, and other things in the extract have already been boiled previously. The contents of the all-grain wort have not.

"Full volume" is a term you'll see all-grain brewer's tossing about for the mash step. Which isn't a boil and isn't something one doing all extract would do.

There's full volume or partial volume mash done by all-grain brewers.

There's also full or partial volume boil done by either.

Then there's partial mash which makes an all-grain brewer an extract brewer and vice versa.
 
I just looked at your instructions. I'd just reduce the water and add it as needed to the boil. But add it to wind up with the desired amount of boiled wort. Not necessarily the total amount of water they told you to add.

Depending on how hard you boil and other things, you might even need to add more.
 
I've never brewed with extract.
I have. And still do. And I BIAB.

If I read #12 correctly, you offer an approach to brewing using a 2x concentrated boil with DME/LME. Back in #4, I pointed to resources that recommend not doing a concentrated boil (and those resources come with reasons one may not want to do this and mention off-flavors to look for).



An OG 50, 25 IBU recipe using DME/LME can be done either full volume or "partial boil (with late additions)" without much difference.
 
If you can, then just try both.. That is; Do the same recipe twice, once as a partial, the next as full..However: A 7-gallon pot doesn't leave you a lot of room for the inevitable boil-over. With care, some people manage it. I'm not one of those..I destroyed one of my stove elements the first and only time I tried to use a pot that only had a couple inches above the wort (approx 6G for a 5G batch) plus; I slopped it all over my stove, countertop and floor picking it up and pouring it through a sieve and funnel into my horribly heavy glass carboy (6G..which was actually too small for the violent fermentation that spewed more the a gallon of beer in primary), and then I had to spend a week or so on pain-killers for my labours. (I have a nasty life-long injury).
I found the full-volume simply tasted 'Better'..the flavours were simply more well defined and it probably had to do with @BrewnWKopperKat 's point number 2 about hops and volume.
Beware the Rabbit-hole though! That experience caused me to begin planning and building my 3V system for 6-12G batches...can get costly.
That said; Not everyone percieves or for that matter brews in the same way.. I've had excellent beers from pretty much every manner of brewing practice, but my own brews are simply 'better' when done full-volume and the journey has been worth it.
:mug:
 
When I was first starting out, I was doing 2.5G boils for a 5G batch since all I had at the time was a 5 gallon kettle. The next couple of batches, I did 3.5 gallon boils to take as much advantage of kettle space I had. This was 11 years ago and back then the reasoning why was boiling closer to full volume doesn't result with the finished beer being darker in color compared to a full volume boil. A lot of info has changed since then, so I don't know if that still holds true or "myth busted". Since then, I've been able to do full volume boils when I upgraded my boil kettle.

That being said, don't think partial volume boils are a bad thing. I think one can still make a great tasting beer either way. In the end if your beer tastes great and puts a smile on your face, that's what matters most.
 
Is it better to boil a full 5 gallon wort, or boil 2.5 gallons and then top up with water?

The recipes seem to say 'full boil if you can, but half-boil-and-add-water is fine too'. Does it make much of a difference?

I do have a 7-gallon pot, so I can make it happen. Just wondering if it makes that much of a difference at the end of the day?
The concern that comes up in my mind is Water Purity.

If you're going to Top off a partial volume boil, it must be Water that has also been Boiled or R.O. Filtered or Distilled. Also be sure the Water addition has also been given the matching water chemistry salts as your Mash water was given.
 
It's the OP's first batch, so maybe we should try not to make things too complicated?

I do five gallon extract batches in a five gallon kettle. I start with 3.5 - 4 gallons of water. Between the volume added by the ingredients and the volume boiled off, I end up pretty close to where I started (depending on how big a beer and how long a boil, of course). Then I top off with water that I boiled and refrigerated the night before.
 
I usually increase the finished batch size to 6 gallons rather than 5. I prefer full boils. The larger batch size gives you better hop utilization and allows you to better separate out the trub.

I run the first 5.25 gallons into the fermenter, and the more trubby end of batch into a 1- gallon jug for fermenting separately for fun (makes about 5 hop-sharp beers, sometimes OK.)
9AD6D696-E70B-445B-B6BC-BC7F555F1644.jpeg
 
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