What does oxidized beer taste like?

2 out of my 9 batches have had a slight off flavor. its hard to describe but it is similar to a sugar water aftertaste with a little bitterness behind it. it isnt enough to ruin the beer but definately noticeable. i used to not let my priming sugar cool after i boiled it, could this be a reason? im thinking its either my priming sugar (5oz per 5gal) techniques or oxidation during racking. any advice?

are you using liquid extract? sometimes that will contribute a 'twang' to batches. i would doubt that you are experiencing oxidation, but it's not impossible.

sometimes steeping/mashing grains at too high a temp will cause off flavors also.

so you just poured 200+ degree priming solution into the bottling bucket and racked on top of it? i would guess it would come down to temp pretty quick since it's not that much compared to the wort, but that may have contributed.

oxydized beer tastes like wet cardboard.....

Not cooling you priming sugar won't effect flavors at all, many people don't.

How young is the beer when you taste it....and does the flavor dissapear when you let it condition for a few weeks?

How long are you letting the beer bottle condition for? It sounds like a green beer taste to me. Or maybe if you are using corn sugar instead of malt added to a kit. Need more details of your brew tecniques.

no. even after a few months the flavor is still there.

i was using LME for 1 and DME for the other. i just use the pre packaged 5oz priming sugar from my LHBS