Bad flavor after being on tap for a couple weeks

[PhillyBrewer]

This issue has been ongoing for me and it's become quite frustrating. I recently thought I had resolved it (this thread) and that it was caused by not turning the pressure of an already carbed keg. But it would appear the issue remains.

I tapped a BVIP I made a week or two ago. When I first tapped it, the beer tasted about as perfectly as a beer I've ever brewed could taste. Simply amazing. Going off my recent hypothesis that the keg on pressure was a problem, I only turned the pressure on to this keg when it needed it and kept the regulator at 6 PSI. It's been on tap for 1-2 weeks and it's started to get the weird flavor I've continually experienced. The flavor is hard to describe, but it's like a bitter-sweet flavor. It doesn't make the beer undrinkable, but just not nearly as enjoyable, especially since I was so fond of this beer when I first tapped it.

Notes about my kegging...

- I quietly siphon beer from my fermenter into a keg, seal it up, put 30 pounds of pressure on it to set the lid, then using the relief valve, I purge for about 5-10 seconds.
- I force carb my beer at 30 PSI for 2-3 days which typically does the trick.
- I clean my draft lines with BLC every time to tap a new keg. I also periodically use a long dip tube brush to actually scrub the lines clean when it looks like they have residue built up from IPAs and such.

Could the beer be oxidizing somehow? Is there something in my actual brewing process which is leaving too much of something in the beer which deteriorates after time?

[manwithbeers]

Any sort of brush will gouge, scrape and scratch beer lines and create great spots for bacterial infections. Change them and clean the shanks, taps, Post attachments and you should be back to normal. In the future an extended soak or recirculated BLC is all you need to clean the lines.

Cheers

[CRBrewHound]

I would say at this point it would be easiest to just take the keg system apart.
Soak the shanks and faucets in star san, blc, and hot water.
Soak disconnects in Star san, blc, and hot water.
replace all the lines on your taps, should be fairly cheap unless you have a long run.

The other thing, I am not sure using a brush on your lines is a good idea, I wonder if you are leaving micro abbrasions in the material that bateria can get into with beer sitting in the lines for extended periods (couple of days).

I have never had a problem with my lines and all I do is when I replace a keg:
1. I run BLC through the lines and let sit for 10 - 15 minutes
2. Run hot water to clear line (hotter the better).
3. Run Star San through lines let sit for 10 - 15 minutes
4. Clear lines with Hot water (hotter the better).
5. connect new keg and run until beer comes.

[PhillyBrewer]

Ok. Will clean the system and replace tubing.

Based off what you're saying, the beer inside the keg is fine, but it gets tainted as it travels through my messed up draft lines? If that is the case, I should be able to connect a new/separate dispensing line (eg. a picnic tap) and the beer should be fine, right?

[animaldoc]

Ok. Will clean the system and replace tubing.

Based off what you're saying, the beer inside the keg is fine, but it gets tainted as it travels through my messed up draft lines? If that is the case, I should be able to connect a new/separate dispensing line (eg. a picnic tap) and the beer should be fine, right?

Maybe yes maybe no. Contamination in the line could very possibly make it's way back to the keg.

If the beer from the tap is off and the beer from the keg is fine, you have your answer and it's in the dispensing portion of your kegerator ....... but if it's off both ways you just don't know the source yet.

[PhillyBrewer]

If I do get the flavor when the beer isn't run through my draft system, what other possibilities are there? Is there something in my brewing process that could result in the beer degenerating too quickly post-ferm?

[BeerPal]

If I do get the flavor when the beer isn't run through my draft system, what other possibilities are there? Is there something in my brewing process that could result in the beer degenerating too quickly post-ferm?

You need to examine your sanitation techniques. Whether it is happening in your draft system or during your brewing sessions, it sounds like you are having contamination issues. How do you cool your wort?

[PhillyBrewer]

Numerous people including BJCP judges have tasted my beers and haven't noticed anything "wrong" with it, per se. None of the textbook off flavors. One noticed what I described, but only after I described it. I'm not sure if my palette is overly sensitive to this or what, but it's subtle which has me doubting it's a sanitation issue.