New Keezer, BAD flavor, carbonic acid?

[bthomp]

Hey All,

It seems there is some skepticism about the carbonic acid diagnosis for off flavors, but I can't figure out what else this might be so I am hoping for some advice. I am newish to kegging; started with a 2 tap fridge that worked great, had 5-6 beers through it and decided I wanted to go bigger. I stepped it up to a 5 tap homemade keezer and got everything around to do it. When I was ready to go I moved a holiday ale that I was 3/4 of the way through to the new keezer, and put a saison and cider in a couple of used kegs that I thoroughly sanitized and replaced all the O rings on. Set temp at 38 and pressure at 15psi. After 1 plus week all of the beer and the cider tastes AWFUL. The holiday ale that I had nearly finished off and tasted great the whole way through until the new keezer (same lines, same everything) tastes super metalic and sharp along with the new Saison and Cider. On top of that the force carbonation seems to be going very slowly. I can't fathom that any infection would move between the kegs, and the fact that the holiday ale was tasting great makes me think it has to be something with the gas/carbonation itself. I took a couple samples into the local brew store and they agreed that it must be carbonic acid buildup or at least it didn't taste like a beer with some kind "off" infection.

So my questions are, why did this happen? How can I prevent it in the future? And what do I need to do to recover these beers? I have read that just letting them sit for a couple weeks will take care of it. Is that the case? Should I depressurize the kegs and start over? Do I need to replace the Co2 tank? Anyone who has saved their beer in this situation it would be great to know what you did. Thanks all.

 

[Bobby_M]

Did you end up with a new tank? Is it aluminum or steel?

 

[bthomp]

The tank is newish, but I had it hooked up to the holiday ale for a couple of weeks before the transfer to the new keezer. I'm pretty sure it's aluminum. I just do a tank exchange with the local brew store and it's what I ended up with.

 

[kegtoe]

Bthomp, any resolution to this? I fear I may be in the same situation.

 

[Horseflesh]

I had this happen once, never figured out why, so I'm interested in the resolution too.

I do not think my case had anything to do with carbonic acid, though. At least in my case I had a known combination of PSI and fridge temp, meaning a known quantity of CO2 in the beer, the same way I carb everything. I also checked the pH of the tart tasting beer and it was in line with other home brews and commercial beers.

I thought about an infection, but the beer went into the keg cold, and the off flavor developed overnight while on the gas. Nothing will grow that fast in ice cold beer, right?

The only thing left, I think, was having a contaminant in the keg I thought was clean.

So, I'm still stumped.

 

[seatazzz]

Are all your lines clean? Purged them out with sanitizer lately? If you somehow got backflush into your regulator that may be the culprit as well. I've been lucky with my lines but my regulator is old and will need to be replaced within the next few months.