For every 10 degrees C, you speed the aging by a factor of 2. Best to keep it cold, or at celler temps. Breweries do accelerated aging by taking the beer up to a high temp, say 140F for a few days.
The most noticeable and, in my opinion, disgusting effect of prolonged heat exposure would be coagulated proteins. I've experienced this more than once with Brew Dog IPA. Basically, the head of the beer will become a nasty, thick, curdled, offensive goop.
This article might be of some interest.It's to do with the effect of raised temperatures on IPA. http://zythophile.wordpress.com/2010/06/17/ipa-the-hot-maturation-experiment/
Dude, simple science. 10 degrees C creates a time warp. 30 degrees C creates a cubic warp. 1911 degrees C creates a Wyatt Earp.
Deschutes did it when testing for infection in the '09 Abyss if I remember correctly. I have no idea of the math, science, or numbers behind what they did, but I know they said exposed it to higher temp to accelerate aging.
I've found that the hotter it is outside , the quicker beer seems to get gone. The same thing also happens the colder it is outside. Regular conundrum right there.
It's a pretty common "rule of thumb" in the industry, if it's the effect of storage temperatures you're questioning as being "real". Here are two similar quotes: "For instance temperature extremes during shipping, warehousing and at the retail store you purchase your beer from can double the "aging" of the beer for each increase of 10 deg. F. That means beer with a "shelf life" of 6 months at 40 F will have a "shelf life" of 3 months at 50 F and 6 weeks at 60 F."Mark Ruedrich, brewmaster, North Coast Brewing Company (in reply to an old BA forum question)“Shipping and storage temperatures are important to beer flavor. Beer contains a variety of compounds that are capable of autoxidation if temperatures get high enough. In practical terms, beer that has been held at 38° C (100° F) for two weeks will have the same loss of freshness in flavor as beer that has been held for three months at 21° C (70° F) or beer that has been been held for more than one year at 4° C (39° F).” Handbook of Brewing By William A. Hardwick, 1995
That may be so, but it doesn't mean the beer is "aging" faster. If that were really true, then Deschutes would label the abyss with "For best results, store in oven on plate warmer setting for 2 days then drink."
The OP's question was the effect of heat on beer, so we're discussing "aging" in the sense of a fresh beer getting old and becoming stale. It's why many breweries print Please Keep Refrigerated on their packaging (a request that is all too often ignored at the retail level). It's not the sort of "aging" (and I've always preferred the term "cellaring" for this reason) one does purposely with beers brewed to withstand longtime storage at cellar temperatures and will hopefully benefit from the changes that time will bring to those beers. I mean, some beers can be said to be aged but some are just old. Granted, that if the OP was asking about "long periods... of warm temperatures" for his cellared beers, he probably should request that the thread be moved to the Cellaring forum.
Maybe I should have said staling instead of aging, which many think of as keeping the beer at 50F (10C for those that are more technical). Aged beer is from the flavors of redox reactions, and those beers go stale given enough time at 50F. Accelerated aging test are known in the industry. Larger breweries with labs do those tests. I may have heard about that at one of the NHC's, either Ray Daniels or Randy Mosher's talks. Or Dr. Bamforth. Search for "the Arrhenius equation" to get the general background on reactions at higher temperature.
Perhaps I should have given more specifics when asking this question. I've got several bottles of beer sitting aside, I'm not really cellaring them per se, but they're not the beers I would just grab when I want a drink either, so I'm saving them for a while (all beers that can be aged however, tripels, strong darks and a flanders red). We're having a crazy winter here in NYC, or rather lack of winter. The heat in my apartment is controlled by the building, not by me, and it's been a bit hot as of late...
