Began trading recently and while I always aim for fresh brews a few have been a bit aged (2-3 months). In these instances (only a few beers) I've noticed that they've had a more sour/tart aspect to the taste. Is this traditionally a sign that an IPA/DIPA is passed its prime or possibly coincidence that the beers were intended to be a bit tart? Should these beers 2-3 months past canned date still be a relatively decent representation of the brew?
If you are picking up sour flavors in a non-sour beer after only a few (2-3) months that is a bad sign. A beer starting to form sour flavors is an indication of an infection from unwanted microorganisms (e.g., bacteria). A hoppy beer (e.g., IPA) that is a few months old is likely to have muted hop aroma/flavor; hop aroma/flavor fades with time due to oxidative reactions. There should be no sour flavors in an older hoppy beer if proper sanitation was practiced during the brewing process. Cheers!
What about sediment? I'm not talking about a thin layer of yeast in a bottle conditioned brew, I mean blobs, for lack of a better description. Stuff that's suspended in the beer, kind of translucent and amorphous. Can be from a few millimeters to a centimeter or so in size. It seems like a flaw to me and very off-putting.
Are you asking the OP this question about his traded beers, or are you asking your own question to the readers of this post? If you are asking your own question, I'd say that you have a beer with coagulated proteins. Is 'snot like' also a description of what you have? That would confirm coagulated proteins and they are harmless. Separate them from the beer before you drink it if they are repulsive.
Can you tell us which beers by name? Some IPAs recently are mean to have a sour tartness. It may be by design in the ever changing blurring of the style lines.
First thing I would do is check the brewer's website to see if the word 'tart' is mentioned anywhere in the beer's description. If so then yeah, it's supposed to be in there. Of course too tart for me might be just right for others so there's that.