Is Lightstruck Beer a Thing With Interior Lighting?

[micraftbeer]

I haven't really thought about this in a long time since I keg everything, and I'm not buying Corona from the store any more... But I recently got a couple FermZilla All Rounders and love them. In my basement, the beers don't ferment in an area where they'd ever get direct sunlight, but it had me wondering about what the exact science is that causes lightstruck beer, and if interior lighting has the ability to do the same thing or not?

 

[RM-MN]

It takes UV light to get lightstruck beer. If your lights give off enough UV so you can maintain a tan without going outside all winter, your beer is in danger of being lightstruck.

 

[micraftbeer]

It takes UV light to get lightstruck beer. If your lights give off enough UV so you can maintain a tan without going outside all winter, your beer is in danger of being lightstruck.

Ah, perfect. "Daylight" bulbs have certain visible light wavelengths to make it look like sunlight to our eyes, but it's the UV part that's the problem for beers. I knew someone would know the answer...

Plus the thought of getting a suntan brewing beer in my basement made me laugh!

 

[AlexKay]

I personally find the lightstruck taste so offensive that out of an abundance of caution I like to cover my fermenters.

 

[MaxStout]

LED bulbs mix RGB to create white light, but nothing in the UV range, so those bulbs are safe for your beer. Old-school incandescents operate well below UV and are also OK. But fluorescents, including CFL bulbs, do emit some UV and near-UV that can cause light-struck beer. Also, keep your beer away from sunlight, as there is plenty of UV in that spectrum.

 

[PCABrewing]

LED bulbs mix RGB to create white light, but nothing in the UV range, so those bulbs are safe for your beer. Old-school incandescents operate well below UV and are also OK. But fluorescents, including CFL bulbs, do emit some UV and near-UV that can cause light-struck beer. Also, keep your beer away from sunlight, as there is plenty of UV in that spectrum.

I had heard that some LED bulbs do have a UV component and that it can be disruptive to wildlife reproduction because it messes with their circadian rhythm. Maybe it's just blue light and not UV. But I'm pretty sure the grow light LEDs do emit UV.

 

[day_trippr]

fwiw, the spectrum that messes with hop compounds actually starts in the blue range and goes from there into UV...

Cheers!

"In the real world, where beers aren’t bombarded by lasers, light-struck beer is due to visible light between 400-500 nanometers in wavelength (the blue end of the spectrum) and ultraviolet light, which has a wavelength of less than 400 nm. "

https://www.livescience.com/33718-beer-skunks.html

 

[RM-MN]

My answer was rather simplistic but the real answer is that it takes a fairly strong UV source like sunlight to do the job quickly. There are stories about fluorescent light in close proximity like in a store display causing skunking in clear or green bottles if they stay there too long. Brown bottles won't be affected as they block the UV.

 

[passedpawn]

LED bulbs mix RGB to create white light, but nothing in the UV range, so those bulbs are safe for your beer. Old-school incandescents operate well below UV and are also OK. But fluorescents, including CFL bulbs, do emit some UV and near-UV that can cause light-struck beer. Also, keep your beer away from sunlight, as there is plenty of UV in that spectrum.

Modern LED bulbs use white LEDs (thank you Cree). White LEDs are actually blue, but the blue is covered with a yellow phosphorescent material that, when combined with the blue part of the spectrum, is perceived by the eye as white. If you open one up, you'll see the LEDs in there look yellow. That blue part of the spectrum from these bulbs has no content under 400nm and is fine with beer.

What you describe is exactly how LCDs (tvs, iphone, etc) produce white.

 

[passedpawn]

I haven't really thought about this in a long time since I keg everything, and I'm not buying Corona from the store any more... But I recently got a couple FermZilla All Rounders and love them. In my basement, the beers don't ferment in an area where they'd ever get direct sunlight, but it had me wondering about what the exact science is that causes lightstruck beer, and if interior lighting has the ability to do the same thing or not?

IMO, you don't need to worry about any light except from the sun.