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EE_
12th November 2013, 03:58 AM
I've wondered how carbonated home-brews are.

Carbonation is very important to how a beer tastes...the last thing I'd want is a flat beer.

Are your's fully carbonated like beers we purchase? If not, can they be saved?

I'm guessing CO2 could be shot through beer.

Libertytree
12th November 2013, 06:31 AM
I carbonate mine in the bottle as I don't have a kegging system. Priming sugar is added at the time of bottling and after a week or so it's ready and fully carbonated.

EE_
12th November 2013, 07:03 AM
I carbonate mine in the bottle as I don't have a kegging system. Priming sugar is added at the time of bottling and after a week or so it's ready and fully carbonated.

So there's no need to ever use CO2?

What about alcohol content? Would you ever add distilled fruit alcohol to beer, to up the content?

Libertytree
12th November 2013, 07:25 AM
Nope, no CO2.

When the beer is finished with fermentation there's still active yeast in it, its converted the sugar into alcohol. By adding sugar at the time of bottling the yeast has more sugar to feed on and those gases produced are the carbonation.

I don't understand the alcohol content question. As far as adding distilled fruit juice to up the alc % I'd have to defer to BT.

BrewTech
12th November 2013, 07:45 AM
Gotta go to work right now, but I would be interested in responding to this thread when I get home...

Neuro
12th November 2013, 12:02 PM
I carbonate mine in the bottle as I don't have a kegging system. Priming sugar is added at the time of bottling and after a week or so it's ready and fully carbonated.
Don't you get a small amount of dead yeast at the bottom of the bottle?

Libertytree
12th November 2013, 01:06 PM
Don't you get a small amount of dead yeast at the bottom of the bottle?

Yeah, it just goes with the territory. It kinda bothered me at first but the work and the trade offs just ain't worth it. You can filter or use a gellatin fining method, the filtration is a PITA as far as I've found so far and using gellatin makes your yeast un-reusable. I don't know if it's true or not but I've read that it's actually good for ya, so I thought I'd opt for the lazy, tight health kick option :)

JohnQPublic
12th November 2013, 04:36 PM
...Carbonation is very important to how a beer tastes...the last thing I'd want is a flat beer...



I was just in the UK, and drank a few hand pulled ales. No carbonation, but still very nice. Seems to be the rage in UK (coming back, retro beer). I was also in the Detroit area more recently, and a local brewery makes GhettoBlaster, which is similar. I think it is tapped with nitrogen. Not as good as the UK, but not bad.

I do like carbonated beers in general.

BrewTech
12th November 2013, 06:54 PM
Don't you get a small amount of dead yeast at the bottom of the bottle?

It's not dead (necessarily), just dormant. That's why yeast can be harvested and repitched into the next batch of wort after a successful fermentation. It's also why, as LT was referring to, beers can be carbonated in the bottle, a process known as "bottle conditioning".

Many homebrewers will collect "dregs" (the yeast left at the bottom of the bottle) out of commercial beers they would like to clone. Usually they're Belgian beers or something rare, and it takes several bottles to get enough. They will then do a yeast starter to propagate a full pitch, enough for say, a 10 gallon batch. It's amazing how authentic a clone beer tastes when it is made with the original yeast...

Anyhoo, to address the OP:

When yeast ferment, they produce ethanol, CO2, and flavor compounds. Every molecule of sugar (glucose, maltose, fructose, etc) utilized by a yeast cell produces 2 molecules of CO2 and 2 of ethanol. During fermentation, a vast majority of the CO2 produced is lost to atmosphere (or in some breweries collected for further processing). Therefore, after transfer to the final package, more CO2 must be added to produce the right amount of carbonation according to brand and/or beer style. There are two ways of doing this.

Most breweries will inject a controlled amount of CO2 into the beer using what is called a carbonation stone. This is a sintered ceramic or stainless steel tube with very small holes in it that atomizes gases passed through it similar to a fish tank aerator. This is called "force carbonating". Physical laws guiding this process are based on gas and liquid temperature and pressure. A good understanding of these principles can be found here (http://www.meheen-mfg.com/Carbonation%20Demystified.pdf).

The other way of carbonating beer is through "bottle conditioning" which is what LT described and what I always did when bottling. After packaging, there is always residual yeast remaining in the beer, and if extra sugar (dextrose, i.e. d-glucose, usually) is added, these residual yeast will utilize this sugar and create carbon dioxide. In a sealed container, of course, the CO2 gas will be forced into solution over time. Unfortunately, if too much priming sugar is used in the presence of excessive yeast cell count, you just made what is called a "bottle bomb". These result in injuries and/or a huge mess.

When Ken Grossman started his brewery in Chico, CA back in the late 70's, he could not afford a carbonation system, so he bottle conditioned all his famous Pale Ale. I've heard that it is still done that way to this day, but i keep forgetting to ask the nice folks from that brewery when I see them. Hopefully my employer will get me into a Beer Camp up there soon, so I can find out for sure.