2 kits - 35 L wort - adding extra water at the end

[trustyrusty]

Hi If you have a 35 L fermentor and use 2 kits.

I am actually asking for a friend LOL

He will have 2 kegs (well 4 in total) - so can adding 5 litres after adding to kegs to make up the liquid - I dont see a real issue but that water was not part of fermentation so would it dilute the taste?
- he wants to do that - but in the end will lose 8 litres of beer. 23 + 23 but will have 19 + 19... He wants to save time fermenting and always have beer..

I guess 5 litres of clean water won't make a difference, and will age with the beer too..

Just putting it out there. Ideas?

cheers

 

[MHB]

It's very doable; in fact a lot of big breweries do so and for the same reasons. To get more beer out of the same sized equipment.

I'm going to say that mostly it’s done by the makers of mass market (mega swill) beers that are perhaps focused more on price than quality.

There are a few very basic points that have to be born in mind.
First is that your diluting water must be Oxygen, Chlorine and Bacteria free. The best way to do this at home is to boil the water you are using and to keep it in a closed container until it’s cool and you are ready to use it. Just put the water in a 5L jerry like a small no-chill.

Some other points to consider are that the same yeast in a heavier (higher OG) brews will taste different.
Depending on your OG, the yeast may not attenuate as far.
At higher gravities yeast tends to throw more fusel alcohols and other metabolic side issues (flavours).

Let’s take a look at the numbers, say you want to keg 2 X 19L (38L) and you would be smart to allow 1-2 L in the bottom of the fermenter for the yeast and other muck that falls out (trub).
2 kits and 2kg of "sugar" in say 30L (leaving a bit of room for foam) will give you an OG of ~1.0594. It’s pretty commonly understood that over an OG of 1.060 the changes in the flavour are going to be quite noticeable. As you are just under that you should be OK (if you want to see how I got the numbers - ask and I’ll run through it for you).
Controlling the temperature (cooling) of the brew will help to suppress esters (flavours). Choosing a more attenuateive yeast and pitching more of it will help to.
I would use the two yeasts that came with the kits and perhaps a packet of something like Nottingham that is quite aggressive and tends to throw less flavours than most yeasts.
Mark

 

[trustyrusty]

Thanks - well I am not sure about the fermentor if it was usable 35 L - ie head room excluded. My fermentor is 25 L but has space at top, so it could be 30 L ..
I was going to ask that question.. Its a brewzilla 35L he is getting...