When drinking beer from a pint glass outside what causes it to go stale?

Question

What aspect of sunlight causes this, would it be uv light, temperature, bring light or a combination of several factors.?

Answer 1

I have never had that happen. When I feel the coolness starting to fade, I drink it.

But I would imagine it's a combination of all the factors.

Answer 2

Its just the release of carbonation in the beer its makes it go stale. Type of beer (ale) also plays a factor theres (pale,brown,dark,light,Irish Red, German, Scotch, Old & etc) the most common are those light ones which taste good chilled/cold & etc. Anyways, like soda, beer contains CO2, I can't say about temperature because other types of (ales) beers in different countries such as UK serves some beers are at room temperature or even warm right out from its tap. Left it out open a day & it doesn't has that bite like the one just got out of tap now this is those beers that served at room temperature.  Its just the releasing of gases into the air that makes it go stale & the type of beer is it which is ment to be served chilled or at room temp.

I know my beers.

Answer 3

You are a stupid drinker if you give it enough time to go off.

A pint of beer should not go off in the sunlight for hours.

Get it down you and then get another one quick!

Answer 4

I'm pretty sure one of the reasons is temperature. Beer is better at colder temperatures, to begin with, but all things basically disintegrate with warmth.

(from my hubby ;P)

Fermentation, its more open to air, it basically deferments it. Its kinda like it getting moldy.

Also, its carbonated, like soda, so being expose to air(?) it gets less carbonated, going flat like soda.

wikifaq/beer

"Bad beer can be easily identified, however, when it has been damaged or spoiled. The two most common occurrences are:

"skunking"

When beer has been exposed to strong light, either natural or artificial, certain components in hops alter and produce acrid flavors, AKA being "light-struck". This is why beer should be bottled in brown bottles. Clear bottles offer no light protection and green is only slightly better. Technically, light of wavelengths from 550 nm and below can cause photochemical reactions in hop resins, resulting in a sulfury mercaptan which has a pronounced skunky character. 550 nm is roughly blue-green. Bottled beer can become lightstruck in less than one minute in bright sun, after a few hours in diffuse daylight, and in a few days under normal fluorescent lighting.

"spoiled"

Also referred to as going "off". This is a more vague term and often refers to beer that has not been properly stored or handled allowing oxidation (a cardboard taste) or other off-flavors resulting from contamination, overheating, etc. As with any fermented beverage, alcohol can also turn to vinegar, imparting a sour taste to beer.

Keep in mind that storing at the warmer end of this scale will increase any aging effects since any yeast remaining in the beer will be more active.

How a beer is conditioned and handled has a great affect on its shelf-life. Beer conditioned in the bottle or cask still contains live, active yeast and should be drunk as soon as possible. Most larger scale, commercial beers have been filtered or pasteurized to remove/kill the yeast and stabilize the product for the longer storage times encountered in the retail world. In any case, stored beer should never be exposed to heat or strong light."

http://www.evansale.com/fresh_beer_artic... :

"Beer is a perishable food, and while it cannot harbor pathogenic organisms as it stales, its flavor becomes severely compromised.  There are five things that cause beer to stale:

    * Warm temperatures

    * Motion

    * Time

    * Light

    * Oxygen"

***DiD ANYONE EVEN CHECK OUT THE LINKS?! THOSE ARE THE FACTS.

Answer 5

It shouldn't unless you are drinking a bad brewed beer...ie alot of micro brews. The sign of a good beer is one you can leave out overnight, opened and in the morning it still has its fizz. Sunlight on the other hand will make it taste a little skunked.

Answer 6

when some 1 chats a load of cods wallop

Answer 7

Beer will not really go stale as you say...It will go flat. However leaving the beer in direct sunlight will have an effect on the beers yeast content and make it taste rank...  

Answer 8

Light and only light would be to blame for a beer going off while drinking it outside.  Beer is still well and good flat and warm assuming it was any good to begin with.

Beer contains hops, this is common knowledge.  Hops lend various chemical compounds to the beer one being isohumulone compounds.  These are inherently volatile molecules that are prone to being broken down by UV light in a process known as "photolysation".  When this occurs the isohumulone compounds break apart in to 3-methyl-2-butene-1-thiol which is a methyl mercaptan.  Methyl mercaptans are notorious for their skunk-like aroma hence the term "skunking".  This process can occur in as little as fifteen minutes to an unprotected beer so it's not uncommon for a beer to turn quickly in direct sunlight outside.

UV light, period.