Beer off-flavors after sitting in keg

[sarsnik]

So we just kegged our first batch of beer, an all-grain clone of Dogfish Indian Brown Ale. We let the keg sit at 50 degrees at 16 PSI for a week and tried it. It was a great beer, maybe slightly green, but there was nothing wrong with it.

I let the beer sit for another week in a in a basement at 45-50 degrees. Then we came home, picked up the keg, and then drove it 45 minutes to be stored in a new keezer in my apartment.

When we tried the beer in the apartment it had developed an off-flavor. I really wish I had a more experienced palate so that I could describe what the flavor is, but my best guess is that it had a medicinal note to it. Maybe even a licorice or root beer taste, but unpleasant.

Any ideas of what the problem might be? We cleaned the keg with a b-brite cleaner I think, and then used star-san to sanitize. The keg was undoubtedly used for rootbeer syrup before, but I know thats common, so I didn't think it would be an issue. We also left some of the star-san foam in the keg, but that shouldn't make a difference. It just seems odd that the beer would taste fine the first week, but off only a week later.

Thanks for your help

 

[stevedasleeve]

I have experienced this before myself. I never found the culprit but my suspicion was the water in combination with the hops. So I began filtering mine. I have not had the same flavor since, though as I said I have not definitively established the culprit.

What I did was rebrew the same recipe (a Centennial IPA) with just the filtered water as the changed variable and the beer came out - and stayed - fine! I should also mention that the hops was from a different source thou it was pretty much the same, Centennial AA 9.3 vs 9.0, so it could certainly have been the hops.

YMMV of course

Steve da sleeve

 

[sarsnik]

Thanks for the reply. It probably would be best to filter the water, though I never ever had that problem with other beers that we bottled.

It seems weird though that I didn't detect anything the first week. Can the chlorophenols develop that late in the conditioning?

 

[stevedasleeve]

I am not at all sure, I did read somewhere that something in the water can combine with some types of hops to give a sort of phenolic aspect. Other possibilities are yeast character and wild yeast contamination. My filtering seemed to do the trick ,though of all my 1 billion beers only two had this, but none since. Good luck!

 

[RedIrocZ-28]

If the keg was used for rootbeer before, thats the issue. Rootbeer flavor cannot be removed from a keg. The metal gets "stained" with the flavor. That keg should be re-purposed for rootbeer only if thats your inclinatio, or sold to someone who intends to use a corny for rootbeer. I've spoken with many people about this, and I have a keg dedicated to rootbeer only myself.

 

[malkore]

I wonder it the top side of the keg was gunked up with rootbeer/cola syrup and the road trip mixed it in?

I oxidized a leaky keg once transporting it on a 3 hour drive. Between not purging enough air (apparently), and then it leaking out after I took it off the gas, it had the dull funk of wet cardboard the next day. previously it had been fine.

 

[jeffmeh]

If the keg was used for rootbeer before, thats the issue. Rootbeer flavor cannot be removed from a keg. The metal gets "stained" with the flavor. That keg should be re-purposed for rootbeer only if thats your inclinatio, or sold to someone who intends to use a corny for rootbeer. I've spoken with many people about this, and I have a keg dedicated to rootbeer only myself.

I do not understand why stainless steel cannot be purged of the root beer smell, and I bet there are quite a few people on here who have done it with PBW, OxiClean, bleach, baking soda, or some other method. The o-rings and any non-stainless pieces should be replaced, however.

 

[RedIrocZ-28]

jeff, I don't understand it either. I soaked my cornies in PBW twice for 1 day each to get the pepsi smell out of them and I've run a few batches through with no off flavors from the regular sodas that were contained in them prior.

However, rootbeer is different somehow. I read a few posts (can't remember where) that said, no matter what, the rootbeer smell was always present, no matter how many times it was cleaned, soaked, etc.

Don't shoot the messenger here. Just relaying what I have read by others who have tried it. I do know that you will absolutely not get the rootbeer smell/taste out of the dispensing lines.

 

[ksbrain]

I wonder it the top side of the keg was gunked up with rootbeer/cola syrup and the road trip mixed it in?

I oxidized a leaky keg once transporting it on a 3 hour drive. Between not purging enough air (apparently), and then it leaking out after I took it off the gas, it had the dull funk of wet cardboard the next day. previously it had been fine.

I was thinking both of these things.

 

[spearko520]

jeff, I don't understand it either. I soaked my cornies in PBW twice for 1 day each to get the pepsi smell out of them and I've run a few batches through with no off flavors from the regular sodas that were contained in them prior.

However, rootbeer is different somehow. I read a few posts (can't remember where) that said, no matter what, the rootbeer smell was always present, no matter how many times it was cleaned, soaked, etc.

Don't shoot the messenger here. Just relaying what I have read by others who have tried it. I do know that you will absolutely not get the rootbeer smell/taste out of the dispensing lines.

a number of people in the soda industry have told me that as well- but i have had success with replacing all the rubber and giving a thorough cleansing. anything porous is tainted forever, though...

 

[sarsnik]

I ended up dumping the keg, and I think the cause of the smell was some kind of funky infection. I did smell a little like root beer after I dumped it, but I soaked the keg in a baking soda solution and replaced the orings - that seemed to get rid of the smell.