Beer tastes stale after first pour from keg

[quiet_dissent]

Hi all,

I've posted before about this issue but the issue persists. My beer tastes lovely after fermentation. It tastes good upon tapping the keg for the first time. However, after I initially tap the keg, most of the flavor profile disappears. For example, I just made an oatmeal stout that I then added vanilla bean soaked in Grand Marnier. Prior to kegging: great. After first pour from the keg: great. A few days late -- Grand Marnier smell is pretty much gone, no more chocolate and roasted notes, no more smoothness. It tastes like old, stale beer that has no body. How is this possible? A few things:

1. I just replaced the tap line. I also just replaced the faucet with a 630SS Perlick.

2. I use the "set it and forget" it method. That is, I rarely set my regulator above 11 psi. For the stout, I set it lower to 8 psi. It has been on CO2 for two weeks upon initial pour.

3. I have replaced all O-rings on kegs.

4. I clean and sanitize everything. (Again, the first pour tastes great! But maybe gross stuff could rear its ugly head well-after fermentation and carbonation?)

Prior to kegging, I never had this issue with a Tap-A-Draft system or bottling; all of my beer tasted the same coming out as it did going into whatever vessel I was using for bottling.

I don't understand. The only thing I can think of is somehow oxygen gets in after the first pour. But that doesn't make much sense given it is a closed system. But I'm convinced I know nothing about this process.

I've been dealing with this keg after keg, each time replacing parts, trying new CO2 tanks, using different cleaners, etc. I get my hopes up that I've solved the issue and then...ugh. It's just never ending but clearly I am doing something terribly wrong. I have wasted so much good beer trying to get this thing right. I have two other possible troubleshooting ideas: kegging water and carbonating it to see what it tastes like after repeated pours across several days and moving some beer to a two liter bottle, letting it sit for a bit, and then reviving it with a carbonator cap.

Any other suggestions or ideas?

 

[billl]

Sounds like oxidation. Are you purging the keg before transfer? Venting a few times before you "set it and forget it"?

You might try carbing in the keg just using some priming sugar and letting it sit at room temp. That would take care of anyO2 you are accidentally introducing.

 

[JonM]

How are you getting gas? There have been examples on HBT where people have gotten bad CO2.

 

[quiet_dissent]

Hey there,

Yes, I do the purge routine to seal the lid/get O2 out.

I do think the culprit is oxygen -- it has that cardboard taste. The issue is out on the first pour everything tastes great (as well as at kegging via sample). It's after it sits for a bit after tapping that I start noticing off flavors and the smell disappears. This leads me to believe that it is something with the Out line. I just replaced the tubing and the faucet, and took everything apart for thorough cleaning, so that didn't fix the issue from previous batches. I'm wondering if it is something with the poppet on the out line that is stuck or something of that sort.

Until I can pin point this better, I am moving to bottles and Tap A Draft. Wish me luck!

 

[billl]

Oxidation doesn't mean O2 was introduced while it is sitting there. Generally oxidation just builds until it's at a noticable level. That can happen if O2 is introduced anywhere in the process.

The chances of O2 getting into a pressurized keg once it is pressurized is 0%. If you have a leak, the gas or beer will be flowing OUT, not in.

 

[BreezyBrew]

Pretty sure it's your line since it's only the first pour.

Check out Kal's Electric Brewery post on different liquid lines somewhere on this forum. They did a test.

 

[quiet_dissent]

I do purge the keg using CO2. If understand what billl is saying, if I tapped my keg today instead of a week ago, it would be oxidized today. In short, it is a temporal issue with oxygen. That makes sense.

Unfortunately, I've had this problem with kegs stored for extended periods of time. For example, I've had a lager sit for months in a keg using my usual procedure for kegging. I tap it. It tastes fine. But within a week, I notice the degrading taste. It seems like if the oxygen is building up and has this point in time when it rears its ugly head, on these kegs that I store for a much longer time, the first pour should taste oxidized. But that isn't the case.

I've never had this issue with bottling or the Tap A Draft, so it is really breaking my heart that I've invested a big chunk of change on this equipment, thinking kegging was the royal treatment, when I've had consistent issues. I had a few successes with a few batches, but in general, I run into problems like this. This has been a persistent problem for the last four or five batches. I keep replacing parts, etc. to no avail. So it likely is something with the way I am kegging despite being extremely clean and having minimal to no splashing during transfer (in addition to purging O2).

I'll have to read up on the tap lines. I literally just replaced the keg line to the antimicrobial tubing. And replaced the old faucet with a brand new Perlick 630SS.

I'm fine with resigning from the keg for now. I'll take good beer over convenience. Maybe when I am older (40 is not old!) and have quelled my need for perfectionism a bit, I'll try again.

Thanks again for trying to help me out.

 

[joshesmusica]

I do purge the keg using CO2. If understand what billl is saying, if I tapped my keg today instead of a week ago, it would be oxidized today. In short, it is a temporal issue with oxygen. That makes sense.

Unfortunately, I've had this problem with kegs stored for extended periods of time. For example, I've had a lager sit for months in a keg using my usual procedure for kegging. I tap it. It tastes fine. But within a week, I notice the degrading taste. It seems like if the oxygen is building up and has this point in time when it rears its ugly head, on these kegs that I store for a much longer time, the first pour should taste oxidized. But that isn't the case.

I've never had this issue with bottling or the Tap A Draft, so it is really breaking my heart that I've invested a big chunk of change on this equipment, thinking kegging was the royal treatment, when I've had consistent issues. I had a few successes with a few batches, but in general, I run into problems like this. This has been a persistent problem for the last four or five batches. I keep replacing parts, etc. to no avail. So it likely is something with the way I am kegging despite being extremely clean and having minimal to no splashing during transfer (in addition to purging O2).

I'll have to read up on the tap lines. I literally just replaced the keg line to the antimicrobial tubing. And replaced the old faucet with a brand new Perlick 630SS.

I'm fine with resigning from the keg for now. I'll take good beer over convenience. Maybe when I am older (40 is not old!) and have quelled my need for perfectionism a bit, I'll try again.

Thanks again for trying to help me out.

maybe just to be sure, on your next kegged beer, just use a picnic tap? it will cost a little more money thrown at this problem, but it would at least help you figure out if it's your lines/tap that are the problem.

it is really quite the conundrum though, because it sounds like oxidation, but I would have to agree with you that it would have showed up on the first pour from the lager. but also, oxidation usually takes quite some time before it rears it's ugly head, so to have it happen in only a matter of weeks would have to mean a ton of splashing.

 

[darby_ross]

Did you ever find out what was causing the problem?