Beer age?

I want to know what the life of beer can be in years. I know wine can age for 40 years and in the 40 years, the longer it ages the better. Now I know beer won't be good after 40 years. I was always under the impression that beer needed to be drank young; Anheuser-bush recommends that their beer be drank in 110 days. Well 120 minute Dogfish Head IPA says you can enjoy it now or let it age for a decade or so....... ??? Is this sarcasm or do they really want you to do that? Since I've been brewing, I notice that my home brew ages very well over the course of a month or two in the bottle. I havn't let one go longer than that. I guess my question is how long will beer last, how do you know what styles will last, and if it will age over time will it really improve? Thanks

I enjoy learning so please elaborate.

And not all wines will be better in 40 years- in fact, most will NOT be good after that long. The "longer the better" adage just isn't true. Some very tannic wines need a couple of years to mellow, but after that they start to decline in quality. It really depends on so much.

I think the biggest factors in aging any beer are oxidation, followed by alcohol content.
Hypothetically, a STRONG barley wine if prepared and stored properly, could last a very long time! A light beer that was oxidized at racking and bottling, and left in the hot sun, would likely last about an hour before it tasted like crap.

I've had a 12 year old barley wine, which was quite nice. But most beers, like most wines, are only good for a few years. Very hoppy beers start losing their nose after 5-6 months.

I inherited some of my FIL's homebrew, which is probably five or more years old.

It's still in good condition: great carbonation and head, very clear, crisp, but the flaws in his technique are still obvious. He was one of those who used sugar instead of extra extract. Very malty, no hop presence at all. Still very drinkable, though!

Here's a beer that gets mixed reviews at 30-35 years old:http://beeradvocate.com/beer/profile/342/12873
Courage RIS, some reviews are good and other seem to have bad bottles. In general, I think RIS's age really well. I am keeping some of mine for the long haul, 10-20-30? years. We'll see how they hold up.

BTW, the oldest wine I've had was from 1897(a Madeira), and was very good. Great classified growth Bordeaux's need at least few years, they don't even offer the bottles for sale unil they're around two years old, and many will age 15-30+ years without batting an eyelash.

From my own naive understanding of the topic, I think it'd be wrong to say that beer necessarily gets better with age. Beer just changes with age. Depending on the characteristics of a particular beer, these changes may give a net improvement, or they may have a more negative effect. I think generally more alcoholic beers age better than lighter beers. I read a couple of reviews by Michael Jackson of strong 18-year-old beers - he described them as "madeirised". Some beers would be improved by having this flavor in, whilst others would be overpowered by it. Personally I'd rather drink younger more hoppy beers.

Yeah I would say they change, sometimes for the better. Our Red Experiment passed the test with my friends the night we debuted it but I wasn't so happy. Just openned one this passed weekend our of curiosity and I have to say, I was much more pleased with how the flavor had developed, it's been at least 3 months in the bottle not cooled just sitting at room temp, and where the outside temp has changed from the 90's to the 30's.

But on the same hand I have dumped many a beer that just tasted old, left in the bottom of the fridge or back of the patry after a party.

There are bottles of Sam Adams Tripleboch on Ebay from 1997 still unopened, could see with the higher alcohol it might age up differently, also a couple 2002 Utopias(barely a beer anymore.) I've got some old liquors that are awesome, 35 year old Jim Beam distillers choice. Had an unopenned Johny Walker Red from the early 80's that was so good.