Filthy off-taste, but beer is healthy....

[GQT]

1 - Fridge.
Only used for beer and yeast. Lower level - up to 4 Corny kegs (currently 3).
Upper level - yeast on slants, hops, whatever.
Fridge is immaculately clean, no spills, no mildew - it is pristine.
2 - APA in keg.
About 2-3L left there, been sitting in fridge for ~2mnths, QD on OUT line, cobra tap there. Pressurized to serving pressure.
3 - Wit in keg.
ABout 12-13L left, been there since 3 May. QD on OUT, cobra tap. Pressurized to serving pressure.

No problem with these kegs, beer lines, taps, fridge, CO2 tank - anything, ever before.

Today, I opened the fridge and there was strong stench of, errr... what? - rubber? band aid? people say these smells are different, but as I have never had problem of this sort before, how would I make difference between them.

I poured myself a glass of APA, and it was hardly drinkable at all (it was fine 48 hours ago). Stench+taste of this rubber/hospital trash.

Now,
- it was perfectly OK as recently as 48 hours back
- keg is perfectly air tight
- beer line had not been removed/reattached
- I had beers sitting there for much longer, no problem

I was puzzled, the least to say. OK, as there was not much left in the keg anyway I decided to feed the beer to Mr Toilet, so I put the keg next to the toilet, bled the pressure and then I had something else to do.
In an hour, the keg warmed up (and the pressure in it built up) so before pouring it out I decided to take another chance. Poured another glass - perfectly fine beer, except warm and flat.
Damn.
Tried a glass of wit - it was OK if a bit rubbery, but I cant make sure whether it was my own paranoia and the foul taste residue in my mouth, or it was really bad.
Just in case took off the line, threw it into sanitizer solution. APA - decided to finish it and throw out what I could not. (well, I managed to deal with all of it).

Stuck my nose into fridge - stench still there, but times weaker.

WHAT COULD THIS BE????

Thanks for any ideas.

 

[kh54s10]

If your tap lines were attached and not leaking, the beer poured tasted bad, but later another did not, it seems that the beer in the line between the keg and the tap somehow went bad.

That doesn't explain the smell in the refrigerator though. Did the power go off? Did something stored inside go bad? I have had something go bad in my refrigerator and you can smell it in the freezer section.

And, having something go bad in the refrigerator, should not have gotten into the beer.

I would clean it out and examine everything in there.

 

[Jaybird]

This is really odd. Was there condensation on the kegs? Could you have a little mold growth somewhere? Doesn't explain the beer BUT if you tasted it after smelling the fridge you know the majority of our taste comes from smell so you could have just "THOUGHT" it tasted bad because you tricked your brain into thinking it was.

Cheers
Jay

 

[GQT]

Thank you for feedback guys, here are a few clarifications...

This is really odd

That's what I am saying, exactly...

Was there condensation on the kegs? Could you have a little mold growth somewhere?

No/No. As I mentioned, the fridge was (is) impeccably clean. I keep my yeast bank there, so it is regularly cleaned and sanitized. I checked all over again - nope, it was pristine.

if you tasted it after smelling the fridge you could have "THOUGHT" it tasted bad

Knowing that, I took my glass out to the balcony where I had a smoke while sipping it, then moved to the kitchen, then walked around the apartment - all just to get different olfactory backgrounds. Nope, crap kept smelling like crap, so perhaps it was crap.

If your tap lines were attached and not leaking

Cobra taps are always something suspicious; cheap plastic is cheap plastic... but yes, they were NOT leaking.

the beer poured tasted bad, but later another did not

A bit wrong. The FIRST beer (that tasted terrible) sat next to toilet while I was busy with other things for about an hour give or take. Before putting it on the death row I bled off the pressure. During this hour the beer warmed up, hence the pressure grew. Before dumping it, I had another glass - it was perfectly OK, except it was warm and nearly flat. Where did the sh!tty taste/smell go??? - I asked the beer, it didn't answer.
Then I tried another beer (wit) that was still in the fridge in its own keg. It was OK, but being paranoid at that moment, I somehow tasted a tiny bit off, so I did the same trick with it: out of fridge, depressurize, let warm, re-pressurize, back in fridge. Will taste it again later today. (the line had of course been disconnected, filled with and and thrown into starsan).

it seems that the beer in the line between the keg and the tap somehow went bad.

I hold the cobra taps suspect. There is nothing else I could theoretically blame...

That doesn't explain the smell in the refrigerator though.

That could, in fact. If the few drops of beer remaining outside the lock in the cobra tap went bad, there might be some smell. But then again, "some smell" is not a correct description of what I felt opening the fridge last night. A "devastating tsunami of stench" would be more accurate. A couple of grams of beer no matter how bad could not produce that much odor.

Did the power go off? Did something stored inside go bad?

No/No. This fridge is kept almost sterile and is cleaned on regular basis... besides, I checked it last night again.

That's a puzzle guys.

 

[Turkeyshot]

What about the drip pan under the fridge, maybe something died in there. Is this fridge in the house or your garage?

 

[IslandLizard]

Could it be the line between the keg and cobra tap? Regular, non beverage grade PVC has a horrible plastic/bandaid/medicinal smell and taste. 2 months of beer sitting in it will surely taint it.

 

[GQT]

What about the drip pan under the fridge, maybe something died in there. Is this fridge in the house or your garage?

The pan is bone dry. Always has been; I checked it a few times as I run a fan cable through the drip drain tube, so I want to be sure it is safe.
I live in an apartment, the fridge is right behind my computer desk I am at right now. If anything started stinking outside the fridge I would know it right away.
Damn it is a puzzle!!!

 

[GQT]

Could it be the line between the keg and cobra tap? Regular, non beverage grade PVC has a horrible plastic/bandaid/medicinal smell and taste. 2 months of beer sitting in it will surely taint it.

I only use medical grade plastics in all my setup!..

 

[IslandLizard]

I use a spare fridge (it actually doesn't "fridge" anymore) for warm fermentations, saisons, diacetyl rests, etc. There's a small heater in it. Whenever I open that fridge up, it has a weird plasticy, phenolic smell. I even thought the current Saison fermenting in there @75°F went bad and expected a wild fermentation and a monumental pellicle when I opened the bucket. Nothing! Just great beer, about half done. Took a small sample, sealed her up again, and blew the headspace out with CO2.

Now a cold fridge typically smells cleaner unless something is spoiling in there. Very puzzling, curious to hear what it turns out to be.

 

[GQT]

curious to hear what it turns out to be.

It's getting "stranger and stranger".
So far the only parts still retaining the stench happened to be the short silicone tubes (roughly 2 inches) that I put on the cobra taps' spouts.

My wife has a lot more sensitive nose than mine is (and a lot cuter, too), so she sniffed all the pipes, QDs, taps, etc. - and her verdict just proved my guess. I took off these short tubes, and 15 minutes later blindfolded my lady and let her sniff the tubes and (separately) the taps. I held those before her nose with stainless tweezers so my skin smell would not distract her. She immediately told the tubes from the taps: the taps themselves did not smell, or at least not that bad.

OK, so we sorta located the epicenter of the stench. But so what?
WHAT caused it? Even if, as I mentioned somewhere above, the few drops of beer remaining in the spouts outside the tap lock went real bad, I can't imagine anything going as bad as to foul the whole darned fridge... Besides, OK, let us presume it could. But then why THIS sort of smell? I would not be surprised if it was sour, bitter, schmitter, moldy, schmoldy or whatever - but so very characteristically rubbery-medicinal smell would be the last I'd expect. My beers never come in contact with chlorine sanitizers, and the smell of autolysis (which is as I had read it somewhere also "rubbery") would be totally out of place in as little as a drop or two of beer left in the tap spout at +1...2 degrees C.
Silicone tubes are all medical grade. They were just slid on the tap spouts, no glue or whatever...

So now we have the crime scene but who is the criminal?!

 

[FatDragon]

You've been to the hospitals here... I'm not sure that anything "medical grade" in China is as pure or clean as we'd like it to be.

Also, to clarify, you've got your beer line (clear PVC?) connected to the keg, then a little shim of silicone tubing connecting the beer line to the cobra tap? If so, that might be a weak point in your system that exposes the beer in the line to spoilage or infection. I use a similar silicone shim to connect my racking cane to the spout on my bottling bucket and although it looks like it seals on pretty tightly, I definitely get some air bubbles in the racking cane under certain circumstances.

Thinking about it a bit further, if that silicone shim is loose enough to cause spoilage, it should also be loose enough for beer to seep out which isn't happening, so I'm probably on the wrong track, but maybe this will inspire some troubleshooting that helps lead to the actual culprit...

 

[GQT]

not sure that anything "medical grade" in China is as we'd like it to be.
beer line (clear PVC?) connected to the keg, then a little shim of silicone tubing connecting the beer line to the cobra tap?...

Hospitals may be like gas station crappers but hospital supplies generally speaking are OK. I buy hoses from the same supplier and they have been OK so far...
NO PVC, except on CO2 line. Silicone only for anything that comes in direct touch with beer. Silicone takes boiling and oven baking, PVC does not.
So there is a keg, a QD on it, and a length of silicone tube running all the way to the cobra tap with no joints or anything, one solid piece of silicone tube.
Then, post the tap lock, there is naturally a short tap's own snout that I found not handy enough, so I extended it with two inches of silicone add-on.
So technically speaking, the last 2 inches of silicone are in the dirty zone, outside the tap lock. And this very little piece of silicone does all the stinking.
I might presume there was something wrong with this particular batch of silicone hose, but I just kegged another beer that fermented in a carboy with all in/out lines made of the same tube, cut off the same roll. No bad smell, so it is officially cleared (for now).

 

[MaryB]

Did you have a power outage at all? A chance for the beer in the kegs to warm then get cold and pull beer that may have gone bad in the tap back into the line spoiling it?

 

[GQT]

Did you have a power outage at all? A chance for the beer in the kegs to warm then get cold and pull beer that may have gone bad in the tap back into the line spoiling it?

As a bit of a tecchy guy I really appreciate and love your idea - yes it would have reason, and logic. But I know there was no outage as I had a yeast culture on a stirplate, and if it had stopped, the bar would have been thrown off. However it was on and working...

 

[Jaybird]

Sounds like a mystery.....

Cheers
Jay