Help me diagnose my keg line problems!

[mjw210]

I've had a 4 tap kegerator that i built for the past few months now. For about 2 months everything was perfect, but recently I've noticed an off flavor in some of the beers. I've heard of vinyl off flavors from lines, but this is a medicinal like flavor almost, stings your nose a bit. At first I thought it was acedylhyde since it showed up immediately when I tapped my black IPA (3rd beer on that tap), but it didn't taste cidery enough and using a picnic tap to go straight out of the keg I've isolated the problem to the beer lines. This problem is making the black IPA undrinkable, and I've started to notice it in our newly tapped IIPA (both tapped around the same time, 3rd beer through the tap for the IIPA)

We normally rinse the lines out and star San them before retapping with a new beer. I haven't done a full cleaning yet, but since this is impacting two taps I decided to completely clean out the lines. Ran hot water > recirculated BLC for a few minutes > let stand for 10 min > recirculated BLC for a few minutes > let stand for 10 min > ran hot water. I did this on all 4 taps.

Tried the beer again today and that flavor is still there. The odd thing is that it's barely noticeable on the IIPA and very strong Black IPA (both 3rd beers through the lines) but non-existent in the cappuccino and skeeter pee that we have on the other two taps (both 2nd beers through the lines). We're using 10 ft of whatever beer lines Midwest sells as the standard liquid out lines.

I'm at a loss on what to do now. How do I remove this flavor? Any thoughts?

 

[dryboroughbrewing]

If you're positive it's your lines, then just replace them. I use
http://www.farmhousebrewingsupply.com/scripts/prodView.asp?idproduct=300
It's unpleasant to get on/off the barbs but works well otherwise and is pretty cheap.


That being said, that nose burning medicinal smell sounds like chlorophenols to me. Do you do anything to your water when you brew?

 

[mjw210]

I'm positive that it's in the lines. When I drink out of the keg it tastes fine, but when I drink out of the tap it tastes....very off. My confusion is that its very noticeable in one, somewhat noticeable in another, and non-existant in the other two. If it were the material of the lines, wouldn't it be present in all 4?

And I did consider chlorophenols. I live in Minneapolis and they put chloromines in the water, but I've only started using campden tabs recently. I even remember one of these batches having a strong chlorine smell. But if chlorophenols where the issue, wouldn't they be present in the keg as well?

 

[dryboroughbrewing]

They definitely would be present in the keg as well, if you're up for an experiment you could flush the stout line and run a few glasses of IPA through it. Perhaps the flavor of the stout is masking the taste?

 

[mjw210]

I'll definitely try that, it should let me know for sure where the issue is coming from.

 

[mjw210]

Just tried the black IPA out of the stout tap and it tastes as beautiful as I had intended, zero off flavors. The problem is definitely the line that the Black IPA uses.

But why would the one and to some extent a second line have issues, but the other two have zero?

 

[dryboroughbrewing]

One more experiment, try running off a glass of the beer after not pouring from one of the bad lines for a few hours. Then run off a second glass, taste the second glass first, then the first glass. Is the first glass much more unpleasant to drink? (I'm testing the thought that it might be that the beer is picking up flavor from the vinyl from sitting in the lines.)

 

[mjw210]

I've actually thought of that already. It's slightly less unpleasant when I run a second glass, but because the lines are so thin and there's 10 feet of them, its picking up the flavor no matter what.

 

[beaksnbeer]

Had the same problems with taste problems so switched to Bev-seal ultra no more taste problems

 

[raouliii]

Midwest site states: "3/16" beer/gas line is FDA-rated, odorless and tasteless". What kind of lines are they? Are they labeled?

 

[mjw210]

Not labeled, I'm guessing just some generic vinyl tubing. Just purchased some of the bev-seal ultra, I've put too much time/effort/money into a custom kegerator to have it rendered useless by some crap tubing.