Straight Dope January 28, 2011: Brown bottles better for beer?

[Una_Persson]

From: Are brown bottles better for beer? - The Straight Dope

*Dear 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.

— David*

Cecil replies:

Although we spurn outright trivia, David, we recognize that some of the questions we deal with at the Straight Dope are more consequential than others. The theory of relativity, species collapse, and so on … this is the stuff of party chatter. Every so often, however, we get to settle one of the great questions of our times. Today is such a day.

Despite the occasional introduction of civet feces (no joke) or other eccentric ingredients, beer is an essentially simple product, typically made from water, malted grains, yeast, and hops. These seemingly uncomplicated fixings give rise to more than 600 volatile compounds, with chemical reactions continuing the entire time the beer ages. As with most chemical reactions, heat speeds them up, as can the energy in light. Some of these reactions can yield a mellower flavor. Too much light, however, and your brew may be “lightstruck,” meaning you get skunky beer.

The rest of the column is at the link of course. I’ll note it was pure coincidence that the liquor as an antiseptic column ran just last week.

[bup]

Thus we learn that licking clear-bottled beer off the back of your knee would not be as dangerous as the flavor would imply.

[glowacks]

How exactly was the taste test double-blind when the article describes the same two people running the experiment and doing the taste test?

[Una_Persson]

@glowacks

How exactly was the taste test double-blind when the article describes the same two people running the experiment and doing the taste test?

The definition of “double blind” is that the test subjects and researchers do not know what are the controls and what are the samples. So the process was:

1. 4 identical glasses are used. Small square labels are placed on the bottom of each glass.
2. Person A leaves the room. Person B enters and writes a coded number on each label, and then pours each beer carefully into each glass, noting which corresponds to which label.
3. Person B leaves the room, and Person A enters, and switches the glasses around in order on the table, without seeing the labels.
4. Person A leaves the room, and Person B enters and rotates the glasses again.

At this point, no one knows which beer is in which glass, other than by guessing from taste and odor. After all the evaluations are done, the glasses are dumped in order and turned over to show which was which.

[harddavid]

As always, the great unwashed masses can rely on the thorough, objective and scientific answers provided by the Straight Dope team!

This was my question, and I have to 'fess up to the fact that I had convinced myself this was nothing more than the typical marketing doublespeak we encounter all the time … so, clearly (:smack:), it’s time to eat my words and wash 'em down with a glass of Sam Adams!

• David :dubious:

[Hoopy_Frood]

It’s the same reason that wine (especially red) frequently comes in dark bottles. The process for making wine and beer is very similar, the difference mainly comes down to wine coming from juice and beer coming from boiled grain.

My girlfriend’s a home brewer and always uses dark bottles. And, as this article showed, if light doesn’t get involved, the color of bottle doesn’t matter much. Hence why you can find clear wine bottles, but they’re rare, particularly from a store where they are frequently exposed to light. All light will eventually cause skunking (flourescent, incadescent, sunlight), it’s just sunlight is by far the worst culprit.

So if you can fully control light exposure, use any bottle you want. Especially since clear bottles are cheaper and easier to recycle. However, it’s difficult to insure minimal light exposure, even for homebrewers, so dark bottles are safest.

[swihart]

Cecil – Clear is not a color. Green beer and wine bottles are generally also clear.

Hoopy – Wine does not contain hops. Hops + light = “skunked” beer. Light does not affect wine in the same way that it does beer because of this.

Linda

[glowacks]

@Una_Persson

The definition of “double blind” is that the test subjects and researchers do not know what are the controls and what are the samples. So the process was:

1. 4 identical glasses are used. Small square labels are placed on the bottom of each glass.
2. Person A leaves the room. Person B enters and writes a coded number on each label, and then pours each beer carefully into each glass, noting which corresponds to which label.
3. Person B leaves the room, and Person A enters, and switches the glasses around in order on the table, without seeing the labels.
4. Person A leaves the room, and Person B enters and rotates the glasses again.

At this point, no one knows which beer is in which glass, other than by guessing from taste and odor. After all the evaluations are done, the glasses are dumped in order and turned over to show which was which.

Ok, I basically thought “who is keeping track of which is which?”; I realized that there may have been a way, but was more wondering if it was one of Cecil’s sly jokes and wanted to determine if the tasting was actually done with proper controls.