I'm about to make my first brew (from an extract kit), it's a 25litre batch (6.5us gal). Following John Palmer's advice I will be doing a partial boil. But the biggest pot I have available is 6litres (8qt). Can I do the boil in this pot, and top-up or should I forget the boil and just follow the kit instructions (add ingredients to 25l of hot water).
What are my options?
Edit: (after reading this question) if using pre-hopped extract, do I need to boil at all?
The boil is important for achieving certain beneficial changes in the chemistry of the wort that include the dropping out of haze creating proteins. So don’t forego the boil, even if it’s only a 6-liter partial boil.
The main issue with boiling a small quantity of wort is that you'll get caramelization a lot sooner than if you were to boil the extract in a full 25 liter batch. Caramelization may make the beer a lot darker than its style requires if you are making anything lighter than a bock, and it will also give the beer a kind of burnt flavour. If you are making a dark beer anyway, then it doesn’t matter that much, but anything lighter than a bock will be noticeably darker and taste a bit scorched. But it will still be drinkable; just not “consistent” with the style you might be shooting for.
As such, I would boil 6 liters of wort for no longer than 45 minutes. A full batch, in comparison, would be boiled for approximately 90 minutes.
Remember also that you will get evaporation and if you were to boil 6 liters for 90 minutes, you would lose over 1/2 of your wort! This is why you would actually start a full batch with around 30 liters of wort. After 90 minutes, this would give you 25 liters remaining, and all that extra water will have prevented significant caramelization from taking place.
Also, make sure that the water that you are going to pour the 6-liter batch of boiled wort into is pristine, as boiling also acts to sanitize the wort and drive off any chlorine (such as from tap water). I would recommend getting a 15-liter jug of “spring water” to mix with your small quantity of wort. These are the jugs meant for office drinking fountains and will contain no chlorine.
In summary, definitely do a boil, even if only a 6-liter partial one, but for no longer than 45 minutes, and use a mixing water that is chlorine-free.
That seems low, but it's largely dependent on what's in the kit. It is probably an extract kit. If it's not completely extract and includes some specialty grains you may be in trouble. Depending on weight these will require some steeping and require about 1.25 quarts of water per pound of grains, and don't forget to leave room for the grains in the pot as well. So if this is a partial mash kit, you may be trouble.
If it's completely extract, then I doubt there's any reason that it won't work. At some point you'll have to deal with saturation if you're trying to mix in large amounts of extract into a small amount of water, but I don't think you're approaching that. You might find dry extract a pain in the neck to work with, but I find it annoying in almost all circumstances. You will get better results from having a large pot, but it should be fine to try this first. Don't forget to leave room for boiling in the pot.
With a prehopped extract, I guess you don't need to boil. I'd still want to boil everything just for its sanitizing effect. Also at least heat up the water as it will be easier to mix when it's hot.
1) You can just add it to the warm water. It may already be 'preboiled' and OK for that purpose. Some types of 'beer' are not boiled. You may get a hazy brew, but it'll still be drinkable.
2) You can do boils of smaller quantities. 6 liters is actually nearly the same as 6 quarts (at least here in the US), and this is not really enough for the extract, boil water, and room to bubble up. so I might boil the can in two batches. Add half the can to the pot, add water to about 3/4 up and bring to a boil. Boils notoriously overtop, so be careful! Then boil for about an hour (you don't need a vigorous boil as you aren't adding hops), just a happy boil.
Add this to your fermenter with some cold water. Not too much yet, but enough so you don't melt your fermenter - if it's glass you have to cool the boiled wort a bit too or you will break it. If you have loads of chlorine in your water you may want to treat it or use bottled, here our water is fine as is.
Repeat and add enough cold water to make the quantity you want - 5 gallons is typical.
Add yeast, put on the airlock, and you are on your way.
