[paul]

Anyone know what particular wavelengths of light lead to skunking?  Is it all of the visible spectrum, or just a portion of it?

The reason I ask is if it's only certain wavelengths, this might be another reason to consider LED lighting for reach-in coolers...more energy efficient, less heat output, and the possibility to select LEDs that lack the offending wavelengths.

[dean]

I won't say that I know much about lighting but I don't believe LED's are considered flourescent so they should work and I think it is the blue spectrum that causes skunking but I may be wrong.  Easy way to find out if LED's work or not, try it with a couple of beers in clear, green or blue bottles.

[hopfenundmalz]

Skunking is caused by wavelengths in the 450 - 700 nm range.

Sunlight and fluorescent bulbs have light in this range.  Even incandescent has some.

You want to get lights that have wavelengths that are in the yellow to red range, and don't have componenets in the indigo to green range.

[richardt]

http://www.byo.com/stories/issue/article/issues/238-september-2006/1081-mail

[BrewArk]

...The reason I ask is if it's only certain wavelengths, this might be another reason to consider LED lighting for reach-in coolers...more energy efficient, less heat output, and the possibility to select LEDs that lack the offending wavelengths.

Sounds like you need a patent attorney!  Great idea.

[paul]

Hmmm.  The article gives conflicting information.  First it states that light with wavelengths of 350-550 nm causes skunking, then it states that UV light is the problem.  If the range is accurate, it probably isn't reasonable to try to design a light source to avoid it.  I don't think stores would want reddish yellow light in their reach-ins.  But if the problem is predominantly UV, LEDs should do the trick, or at least minimize the problem.

Or maybe brewers could stop putting good beer in green bottles.

[hopfenundmalz]

Once I ran acoss a paper on line that had the amount of light passed vs. wavelength for different colored bottles, and I think it had the input spectra from several light sources.  Too bad I did not bookmark it.

Flourescents do have spikes in the visible spectum.  They can also have UV, i.e. blacklight.

[hopfenundmalz]

Here is the paper I was talking about.

http://c2.libsyn.com/media/18257/bbrskunking.pdf?nvb=20100706123052&nva=20100707124052&sid=c927a22948e4d5654611c545430ccca5&t=09c89f7e1ddbf66afd0d1