How does a IPA that is over a year-old have some complexity?

It is probably not "skunk" since if you've ever smelled a real skunk you'd recognize that very unpleasant smell immediately as soon as you opened the bottle and caught the first whiff.

As for the other part of your thoughts, I once bought a case of DFH 90 min. IPA that I deliberately drank over 10 months. My review on this site was written during the 9th month.

http://www.beeradvocate.com/beer/profile/64/2093/?ba=drtth

 

If you get a beer that's skunked you'll know it, it literally smells like a skunk's spray. Chemically the scent is extremely similar if not identical (someone more knowledgeable than I can chime in perhaps).

I've personally never had an IPA and said "you know, this would be better aged", but I've had malty-hoppy beers (think Brown Shugga) that I've let sit and, because the malt backbone is well constructed, they can be quite enjoyable even with 8-12+ months on them. Since the aromatics from the hops have all but completely fallen away, the malt is allowed to shine though, which is where those dark fruit/toffee/caramel etc flavors come from.

 

I had a Kona Fire Rock pale ale that was something like 5 years old once. A store somehow found or acquired an old batch and was selling them for about a buck a bottle.

Feeling adventurous, I bought one. It was like a light barleywine, sort of. Certainly not the awful, undrinkable thing I was fearing. That being said, I wouldn't do it again.

 

A few years back I accidentally tucked away a sixer of Lagunitas Brown Shugga in a dark corner of the basement for over 12 months and actually loved the resulting product when I compared it side by side against freshies. Doesn't hold the same surprise factor as your experience, as what was normally a very well balanced bitter/sweet beer became much more tilted toward sweet, which is what you'd expect. But I really liked the result, and would even argue that the mellowed citrus, pine, and sharpness, and increased sweetness and caramel maltiness, made for a tastier overall beer. And I didn't notice any kind of skunking or souring of the beer.

 

From what I've heard it is the same chemical that produces the same smell in both cases.

 

Most IPA's that sit around start to taste like a Barleywine.

 

I think Maharajah and Knuckle Sandwich make okay hyper-hoppy barleywines when aged. Not great.

 

wet cardboard is right on for oxidation, but sometimes oxidation can impart a mild vinous or dark fruit (plum, date, raisin, etc.) character that could be a positive attribute to some tastes. Do you think that could be the "mildly fruity" flavor you taste? This aspect of oxidation is usually associated with darker beers like stouts, porters, old ales, and some barleywines, but I guess it could probably happen with an aged IPA too.

Alternatively, it could just be a mild fruity character of the malts that was always there, but masked by the more intense hops when it was fresh.

 

Oh, stop it! No!

 

Personally, I don't find hops very complex at all. I think they, individually, give very narrow range of flavors, that obviously, when combined give a variety. If you find yourself enjoying this beer, thank the malt bill and yeast. A buddy and I go in every year on a bunch (generally a couple cases) of Celebration, that we drink throughout the year. The beer stays very enjoyable throughout all the changes.

 

How does a IPA that is over a year-old have some complexity?
These flavors can develop regardless of the style some are more prone than others given the conditions are right:

• Bitterness decreases
• Harshness increases
• Fruity and floral esters decrease
• Ribes (catty/black currant character) increase
• Wet paper/cardboard character increases
• Bready character increases
• Sweetness (toffee/honey) increases
• Metallic character increases
• Earthy character increases
• Straw character increases
• Woody character increases
• Vinuous character (wine/sherry/stale fruit) increases
• Meaty-like/brothy flavors can develop

 

I see complexity used all over the place, im kinda wondering what's driving this description, and what it actually is. It's beer, it's usually pretty straight forward IMO, IPAs can be heavy and pine or light and citrus. Stouts can be chocolate , coffee or whatever adjunct they infuse, Bourbon here IMO is always nice. Maybe I'm lacking the palate, but ive never had a head scratcher of a beer or had some type of epifeny after drinking one.

 

Except that barleywine is good and old IPAs usually aren't. Let a SNPA sit around for 2 years and you don't get Bigfoot.

 

I just realized another possible way a fruity character can develop in beer is if there is infection. If you've had any sour beers it would be reminiscent of those flavors... tart citrus or tart cherry. Did it foam up more than usual when you popped the cap? Given how old the beer is if it's infected it would have to be a very mild and slow acting infection. Don't worry, drinking an beer infected beer won't hurt you.

 

Hey that is why i said before in a similar thread regarding freshness

Cheers