Beer v. Sun - Are Brown Bottles Better?

In the eternal battle of truth versus advertising, David asked The Straight Dope's Cecil,

The current ad campaign for Samuel Adams beer makes the somewhat dubious claim that the company’s beer, stored in brown bottles, is better preserved than beer in — eew! — clear or green bottles. So, time to break out your beakers (and beer bottles) and tell me if there is any validity to this claim, or if it's just the usual marketing babble.

So Cecil set some homebrew out in the sun in different colored bottles.  Click here to see the results.  (Spoiler Alert: Brown bottles win.)

The Basics of Evaluating Beer

Andy Ingram wrote an article about how to determine the right beer for you, and in it, he outlined the basics of beer evaluation.  They were good points so it bears repeating here.

1. Look at the beer. Is it clear and bright or is it hazy and murky? This can tell you if the beer has been filtered or not. Filtration is entirely up to the brewer's discretion. . .Unfiltered beers are fine, as long as the haze is primarily yeast.

2. Notice the head. A dense head of foam that coats the glass can indicate quality ingredients. But, more important, it can tell whether your glassware is clean. . .

3. Take a sniff. Up to 90 percent of what we taste is determined by smell. If you're skeptical, think about how things taste when you have a cold. . .

In a lot of ways it's easier to talk about what you shouldn't smell.

One common off aroma smells like burnt butter or butterscotch. It's called diacetyl, and it's derived as a by-product of fermentation. In some beers diacetyl at low levels is not considered a flaw, like English Olde Ale, but for the vast majority of beer this is a sign of yeast stress.

4. Taste your beer. Our tongues can really only taste four flavors, so a lot of what you taste is coming from what your nose has told you. . .Try to notice the body, or mouthfeel. Is it carbonated properly? Is it too bitter or too sweet, or maybe even sour? Is it too cold or too warm? Can you notice the alcohol, is it high or low?