off taste from kegged beers

[kbuzz]

I posted a thread describing this issue before, but couldn't pinpoint which part of my process was causing the issue. So the suggestions I received didn't end up resolving the issue. After reading some threads describing a similar off taste, I think I've narrowed it down to my kegging system.

I'm getting a nasty off taste after my beers have been in the keg for anywhere from a few days to a few weeks. At first I thought it was my water because I was only using tap water...but since have used RO water, distilled water and bottled "spring water"...all eventually give me this taste. Plus everything tastes fine going into the keg.

I'm so bad at describing off tastes, because I tend to use words that lead to different causes. But I would say stale/medicinal/cabbagey, etc...just bad. the taste is especially prevalent in beers that I would consider to have a hoppy character or are ligter in color...but I get it from darker beers as well. I want to even say that it contributes a filmy mouthfeel...a terrible coating in the back of the throat.

I clean and sanitize all my equipment in between each use. I disassemble my kegs, soak in PBW overnight...reassemble. Run the PBW through my beer lines...then rinse the keg thoroughly and fill up with water and run that through the beers lines. Then I use star san in the keg and run it through the lines as well. The star san sits in the lines until my first pull from the keg.

For my last two batches, which I brewed a few days apart, I decided to naturally carb thinking that maybe it had something to do with the CO2 I had been using. I thought maybe if I got the same off taste from naturally carbing then it would have to be the kegs themselves. So in went the priming sugar and I hit it with just a wee bit of CO2 just to seal it (don't think I purged O2 at all, can't remember). I did this with both of these batches and let sit near 70 degrees. Both samples tasted wonderful going into the keg.

A week and a half later I decided to hook up a picnic tap and take a sample w/o using any gas to push through (I know, I know...too early...but even after doing this for over a year, I still haven't developed much patience). Other than being a little undercarbed (but truthfully, not much) they both tasted FANTASTIC!! So at this point I think I've fixed the problem. I let them sit for another week to finish carbing up, then I move them into the kegerator and hook them up to the gas at around 6 PSI...didn't want to overdo it and force anymore CO2 into solution.

After just a day, I'm getting this off taste again.

I've been through the ringer with this stupid problem and the thought of going back to bottling has me seriously depressed. It's got to be either my gas line or my beer line, right? I only had enough PSI to push the beer through I would think. Can gas line or any gas connectors leech off tastes into solution? Could it be my gas splitter? My regulator? My faucets? Any of my washers or o-rings? Should I soak all this in PBW overnight and give it a rinse and hook it all up again or just buy new lines, faucets, etc...? I sure hope I don't have to clean all this stuff in between beers cause it's not easy to get that line disconnected from the barbs...

Or could it be something I'm using to clean? Not rinsing enough?

I've found a ton of threads with people discussing off flavors from kegging, but none with any real solution...

 

[kbuzz]

oh..and I even went to a different gas shop that would actually swap out my tank because someone had suggested that mine was corroded on the inside.

 

[scottvin]

Hey kbuzz, did you ever figure this out? I too am having (from what it sounds like) a similar problem to you. My bottled batches taste fine but my last few kegged have been awful. My most recent one has been carbing around 9-10PSI (40F) for two days and I am starting to taste that flavor (that just seems to get worse).

 

[Rickochet]

Sounds familiar... ever resolve this situation?

 

[sfrisby]

I might suggest two steps. First, how old are your beer lines? I might consider replacing the lines. Second, when you flush with cleaner, run 1/2 of it through the lines then shut off the tap. Let it sit for a half our or so in the lines then turn the tap back on to finish it running through the lines. I do that step when I finish each keg.

Good luck.

 

[Golddiggie]

Could be the lines the beer is going through. I seriously doubt it's the CO2. It could be the lines the gas is going through are leeching something and putting that into the beer. Without knowing what lines are used, and the rest of the system, it's hard to say. I would change all the lines with fresh, known non-leeching, designed for the brewing industry, versions. I've been using Bevlex for my beer lines (3/16" ID) without any problems at all. I'm also using the red, double wall, 5/16" ID line for my CO2 feeds (both from Keg Connection). All the gas side hardware is stuff I'm the original owner of. So there's no issue with something being in there from a previous owner.

 

[jselk]

Could be non-food grade beer lines deteriorating...

 

[Golddiggie]

Could be non-food grade beer lines deteriorating...

Highly likely. Of course, that depends on who built the system up when the hoses were installed. If the lines don't say they're Bevlex, I'd change them. Even if they do, if they're old (more than a couple of years) I'd change them. If they're discolored to any degree, change them. At so little cost, per foot, it's just crazy to not change them when trying to figure this out. Also, the hoses used, IF they're Bevlex could have come from a bad batch/lot. Unlikely, but not outside of a possibility.

If the lines are from a big box store, CHANGE THEM ASAP... Not all vinyl tubing is created the same. Stuff on the shelves there might be fine for running other stuff, but when it comes to beer, use the right stuff. I typically get my hoses from Keg Connection. I make sure to have enough on hand to change over at least two tap lines at any time. I also have enough gas line to replace either my entire system, or a good amount of it. IMO, it's cheaper to get more than you need and store it than try to get the stuff faster when it's an emergency (or a weekend).

 

[Rahahb]

You may try replacing your o rings.

 

[Golddiggie]

You may try replacing your o rings.

The only one that should come anywhere near the beer is on the liquid post poppet, if it has one. I don't count the lid since the brew should touch that enough to matter.