I’m going to be brewing an extract kit brew and was wondering when it comes time for the boil, can I just put in the extra water to boil say 5.5 gallons instead of boiling with 3 and then adding water after the boil to bring it to a resulting 5 gallons? Does it make a difference?
There are 2 problems as an extract brewer that you will face if you try to boil the entire volume of beer.
1. Hop utilization. Hops isomarize better in lower gravity sugar environments. you extract brew at 2 gallons has a hell of a lot more sugar in it then at 5 gallons. Its not really a big issue tho.
2. Post-boil chilling of the wort. if you dont have a way to chill you wort down to yeast pitchable temps(65F) then your beer is sitting in a fermenter in a rather vulnerable state until i gets to that temperature. If your boiling 2G of wort then you can add 3g of cold water to get it pretty cold, if you remove the ability to add cold water then beer spoilers can rear their ugly heads.
IMO you beer wont be noticably better if you boil all 5g unless you have an amazing pallet.
im sure people will add in if i missed anything:)
cheers,
Jeff
Thanks for the response. I have a 10 gal boil kettle so boiling 6 gallons is not an issue. I guess I will go with the smaller volume boil and add the extra water in the primary.
IMO, if you can boil the full volume you should do it. But great beer can and has been made with a concentrated boil.
Neither of the two issues pointed out above is specific to extract, really. A concentrated boil will decrease hop utilization but that can be compensated for by using more hops. If you don’t have an immersion chiller you can always just put your kettle in an ice bath. The quicker you cool the wort, the better, but there are people on this forum who have cooled over night and pitched the next day. IIRC they put the covered fermenter into a lagering fridge or something like that. Not ideal, but with great sanitation it can be done.
One thing to consider is that with extract and a concentrated boil you may get more darkening of the wort than you would with a full boil. This is also easily compensated for by adding a significant portion of the extract late in the boil. This approach works well for a concentrated boil, as you keep also keep the initial gravity of the wort lower and improve hop utilization. If you do not go for the full boil, I would recommend that you add at least 50% or so of your extract late.
So why not just add the total extract late? If you get better utilization of the hops in a lower concentrate, wouldn’t it be best to do the majority of the brew with just the specialty grain wort and then add the extract at the last 10-15 minutes?
That’s a good question. I don’t know if you have enough extraction from the specialty grains to get good utilization from the hops. There may be a sweet spot or threshold of wort gravity that you need to hit. I don’t know. I do know that you want to boil hops in wort and not in plain water. Someone who knows more about the chemistry of hop utilization would need to weigh in on that. You could certainly add the majority of your extract late.
I do partial mashes and add all my extract in the last 10 minutes or so. I typically mash 5 lbs or more of grains though which is a fair bit more than you’d be using for specialty grains.
Someone should run three identical batches side by side. One full boil, one partial, and one with extract in the last 15 min. Send samples to that lab that measures IBU. Then we’d know if it’s hop utilization or hop presence