Newest Threads

GnvBrewer80 · 09-06-2008, 06:12 PM

Hi group,
I'm fairly new to kegging, and need a little bit of insight (or advice). I've kegged about 5 batches now and try to be quite religious about cleaning kegs, beer lines, faucets, etc before moving my finished beer into the chest freezer.

I have noticed on all my batches an odd, almost metallic or sour flavor to my brews when they first come out of the tap and into my pint glasses. It's not overly offensive, but I can tell that it's an off flavor to my brews. In other words, the beer tastes great when I pull a sample to taste in my secondary but something happens once it goes into the keg.

This off-flavor tends to disappear as the beer begins to warm up or gets exposed to air once in the pint glass. Carbonation is great; I keep it at about 10-11 PSI depending on style. My carbonation technique is to hook the gas up to the keg and run it through the beer out line at about 15 psi for three-four days, then I switch the gas to the gas-in line port and let it sit for another week or so before really trying to drink the beer.

I am wondering if the CO2 has any unique sour flavor that I might be tasting, or if something else is going on? Any help or insights from other brewer would be very much appreciated. I also have the cheaper brass faucets but am considering upgrading to the SS models if this could be causing the off-flavors.

Cheers!
Alex

fratermus · 09-07-2008, 04:37 PM

Quote:

Originally Posted by GnvBrewer80

Hi group,
I am wondering if the CO2 has any unique sour flavor that I might be tasting, or if something else is going on?

CO2 in solution is expressed as carbonic acid, IIRC. You can ID this flavor by drinking a fresh coke v. a flat Coke.

I don't know anything about kegging, but I suppose if the beer were overcarbed this carbonic acid flavor could be overly present until some of it came out of solution and outgassed.

**Bobby_M** · 09-07-2008, 05:05 PM

In the little that I've read about carbonic acid, the higher pressure of CO2 you have, the more acid is formed. That's why beers that are highly carbonated will have more acidic bite to it. I don't have any hard evidence, the I'm pretty sure quick or burst carb methods produce a LOT of it. They always taste harsher than the ones I let carbonate over two weeks.

drunkendog · 09-07-2008, 06:05 PM

Quote:

Originally Posted by fratermus

CO2 in solution is expressed as carbonic acid, IIRC. You can ID this flavor by drinking a fresh coke v. a flat Coke.

You can also just take the CO2 hose coming out of the regulator (with it on) and stick it in your mouth for a second to taste the gas. Don't inhale

thebull · 09-08-2008, 01:14 AM

I always pull about 1/2 oz into the glass first, just enough to cool the tap, and then dump it. If you drink that little taste it has an off flavor. In my setup, if you don't cool the tap first you get a beer with a lot of foam so this method serves two purposes.

GnvBrewer80 · 09-09-2008, 03:03 AM

Thanks for all your comments; I think I figured something out last night. I have a Red Ale and Nut Brown in the chest freezer right now. The Red Ale has been in the freezer for a couple of months now, and was still getting the odd flavor. Last night I dialed down the regulator from 10.5 PSI to about 8.5 PSI and vented the keg to remove any remaining gas. About 30 minutes later, I took a sample AND THE BEER TASTED GREAT! I could actually taste the nice balance between hops and malt that a red ale is supposed to have.

So, this leads me to conclude that it was carbonic acid or something to do with too much CO2 in the keg. What do y'all think; is this the correct conclusion?

I also think I have been rushing the force carbonation process a bit much in hopes of drinking the beer more quickly (ahh I hate to wait!). I think one of my critical errors might be in trying to force carbonate the beer at room temperatures. I think I would be better served getting the beer at serving temperature and THEN carbonating it. Does this seem correct?

Alex