Kit only?

[morgs]

Hi again,

Let me know if this is a stupid question but hypothetically speaking could one brew a beer with a can only? ie No added sugars and approximately half the water added. Has anyone tried this, and if they have how much water should i add to achieve a similar alcohol percentage? Would it end up too sweet? Maybe some hops to compensate. I have a fresh wort container that i was thinking of putting to good use.

cheers
morgs

[lethaldog]

You can brew with kit only but if you add the volume suggested on the can ie: 23 litres without any malt or fermentable sugars then you would end up with a light beer around 3.5%

[morgs]

so bout how much would you make it up to ya reckon 10-15litres?

[lethaldog]

I have never done this but id say bout half, lets say 12 litres but maybe someone else could give you a bit more accuracy.

[JubJub]

I'm guessing that you would have to keep an eye on the bitterness if reducing the volume too much.

Jub

[nt]

It will be bitter. Try malt shovel, 1 can made ~12L brew. Another alternative is to use unhopped kit and boil some hops your self.

[morgs]

Thanx guys,

Ya reckon its worth converting a fifteen litre fresh wort container into a fermenter or anyone done so? My guess is it would be hard to clean being only a small hole up top.

[pacman]

Hi morgs,

Check out the currently active topic on "Two can brew: Coopers APA & Coopers Lager".

My local HB man told me 2 can brews were a no no, but I read on a NZ forum that some Kiwis are into 2 can brews, so I decided to experiment using one can in my half size MSB 11.5L fermenter.

So far, so good.

[shane_vor]

I have a two can brew running at the moment, it's only coopers and one of the cans a stout but I thought I'd give it a run, let's see how it goes.

[Stangas]

it makes sense to me..

we use one can and then another kilo of sugars.. in which ever form.. but we all recommend the malts ect. and thats exactly what a can is

bitterness is the only issue.. too much?

i have been doing it for about 6 batches now.. and it is so much easier than using sugars. Cost is slightly higher.

[111222333]

i stupidly decided to do this. the stupid thing was not this idea, i recons its a good one, but the way i did it. i put 1 can, some crystal into my coopers 30 lt fermentor and only filled it to 12. Not a good idea. too much head space, hence to much oxygen for the yeast to nible on. the sugars have been consumed, but i recon its only about 2% alc (fermentation only occurs in anaerobic contitions). we'll see how it tastes in a month or two

[shane_vor]

Thanx guys,

Ya reckon its worth converting a fifteen litre fresh wort container into a fermenter or anyone done so? My guess is it would be hard to clean being only a small hole up top.

nah not too hard to clean. I run similar setups just soak and use a bottle brush for the 'stubborn stains' easy. go nuts mate give it a go!

[rwh]

i put 1 can, some crystal into my coopers 30 lt fermentor and only filled it to 12. Not a good idea. too much head space, hence to much oxygen

I disagree. The volume of oxygen in that much head space wouldn't be that high, and would be purged by the CO2 that the yeast create pretty quickly. Normal brewing technique calls for aeration of the wort, and I go to great lengths to get as much O2 in there as possible when I do my brews.

Just take the good old advice: don't worry and have a beer! Seriously, I reckon it'll be fine.

[r.magnay]

Yeah,
I'm with, rwh, you can brew in open containers quite successfully so what has the head space got to do with the amount of O2 available? The Co2 would still displace it as rwh has stated!

[111222333]

i've bottled now, and it taste great otta test jar, but the point is that the yeast only produce CO2 when there is no O2, so the yeast use much more of the sugars to use the O2 before they can start producing alc and CO2 (ie ferment), by which stage there isnt as much sugers to produce alc. btw, 1 can morgans old + 100g crystal + 50g chocolate grain = black gold, altho the roasted almost coffee flavour may not be for some (just lose the chocolate grain).

[blandy]

Production of CO2 will always occurr whether in the presence of oxygen or not:

(glucose) + 9(oxygen) ==> 6(CO2) + 6(water) (aerobic respiration)

or without:

(glucose) ==> 2(CO2) + 2(ethanol) (anaerobic respiration)

In fact, this suggests that more CO2 (but less alcohol) will be produced when there is more oxygen available, and could hint at why some people say you should leave a bit of headspace when bottling.

However this is subject to equilibrium constants, the preferred reaction of yeast and such that I cannot be bothered looking up.

[111222333]

Production of CO2 will always occurr whether in the presence of oxygen or not:

(glucose) + 6(oxygen) ==> 6(CO2) + 6(water) (aerobic respiration)

or without:

(glucose) ==> 2(CO2) + 2(ethanol) (anaerobic respiration)

In fact, this suggests that more CO2 (but less alcohol) will be produced when there is more oxygen available, and could hint at why some people say you should leave a bit of headspace when bottling.

However this is subject to equilibrium constants, the preferred reaction of yeast and such that I cannot be bothered looking up.

ok my bad, completely forgot that glycolysis isn't the only step that glucose is used in under aerobic cond. (and even that produces 2 CO2 ) - its sad when you cant even recall stuff you went over last semester, and have been learning the last three years.

and the preferred reaction is almost completely towards citric acid cycle cycle, although its more to do with inhibitors regulating fermentation than the equilbrium constants.

[blandy]

111222333,

No worries, I think the main thing to take from this is that yeast knows what's best!

[drtom]

The mention of the citric acid cycle had been stewing away in the back of by head ever since it was mentioned, and the reason only just occurred to me.

One of the main concerns about oxygen in the head space is not its effect on the yeast, but its effect on other elements of the beer. There are lots of compounds in it which will oxidize and produce off flavours if given sufficient opportunity, however, the amount of oxygen in a centimeter or two of head space isn't going to have much effect.

Phew, I can sleep easy again.

T.

[50% Mogman]

The yeasties should gobble all the O2 in the bottle headspace if you bottle prime.