You definitely know when you run into one. A beer that smells like skunk…So why does this happen?
Here’s the deal…
Skunky beer is a buzz-kill (In more ways than one). And although skunked beer is becoming less common, it’s never a good thing.
Skunky beer is a widely-known flavor defect…everyone seems to have a theory as to what causes beer to go funky…and many of those are wrong.
It’s commonly thought that skunky beer is the result of temperature variations, turns out it’s not. Skunky beer (sometimes called “lightstruck beer” is the result of the beer’s contact with light.
In 2001, researchers at the University of North Carolina at Chapel Hill figured out what causes the skunked beer phenomenon according to LiveScience…
The scientists bombarded Isohumulones (also known as alpha acids), the bitter compounds in hops used in beer, with lasers.
And that process caused the Isohumulones to break down quickly and morph into MBT (3-methyl-2-butene-1-thiol), an incredibly potent compound, similar a chemical found in skunk’s gland that some people can detect ‘at concentrations as low as one-billionth of a gram in a 12-ounce beer,” according to Chowhound
So why is skunky beer becoming less common?
Well there’s a number of reasons not the least of them being the beer industry’s escalating migration from bottles to cans. Bottles are obviously more vulnerable to light’s impact…
In the real world, where beers aren’t bombarded by lasers, Skunky beer is the result of contact with light between 400-500 nanometers in wavelength and ultraviolet light, which has a wavelength of less than 400 nm.
“Brown bottles block out light under 500nm, and green bottles block light below 400nm,” according to LiveScience “which is why the occasional Heineken will taste off. And, clear glass provides zero protection against light, which is why Corona advertisers cleverly suggest you drink their brew with a slice of lime.”