[majorvices]

Good stuff - I think I know exactly what you guys are talking about.

[hopfenundmalz]

  to me it is just a stale taste.

If it is quick oxidation this is what I get as well. The longer it develops the more "sherry wine" like it gets. The wet cardboard is a decent analogy as well.

And I'm glad Gordon also mentioned the weird caramel taste that oxidized beers have.  That's something I perceive, too, that you don't see get mentioned much.

Yeah, just go to Germany and have some Ayinger or Spaten or Paulaner or whatever and then come back to the States and buy some dusty bottles of the same off the shelf. That will make anyone understand the caramel/sweet aspect of oxidation.

In lighter German beers in the states, I often pick up a honey flavor, which is oxidation.  The compound is 2,3-pentanedione, and some discriptions say it has a caramel taste.

[bluesman]

  to me it is just a stale taste.

If it is quick oxidation this is what I get as well. The longer it develops the more "sherry wine" like it gets. The wet cardboard is a decent analogy as well.

And I'm glad Gordon also mentioned the weird caramel taste that oxidized beers have.  That's something I perceive, too, that you don't see get mentioned much.

Right. I notice a shrinkage of flavor level or less intense (brightness or freshness) flavors. Boxy or cardboard and sherry are classic descriptors which to me are most accurate. I've also experienced some slightly metallic flavors in older beers.

I think Gordon hit the high notes of this condition. The best way to recognize this is to do a blind tasting of like examples a few years apart, of course easier said than done.

[denny]

Yeah, just go to Germany and have some Ayinger or Spaten or Paulaner or whatever and then come back to the States and buy some dusty bottles of the same off the shelf. That will make anyone understand the caramel/sweet aspect of oxidation.

I'm extremely lucky in that our local bottle shop has all of those in excellent condition.