sunlight - Page 2

MedsenFey · 12-23-2011, 08:07 PM

Quote:

Originally Posted by Brewskii

The sunlight will not effect the fermentation or yeast. What sunlight ( and many other light sources ) does is attack a weak covalent bond in the humulone molecule from the hops. This molecule will then form a stronger bond to atmospheric sulfur and form a chemical compound similar to that in the musk gland of a skunk.
If you have ever had skunky beer, light is what caused it. It's an off note referred to as "light struck".

Quote:

Originally Posted by Brewskii

Unless you making mead in which case none of that applies.....

Whoops

Actually some of it applies. Even if there are no hops, wine and meads contain other compounds such as riboflavin that can interact with UV radiation to produce sulfur odors. This is referred to in France as goût de lumière - but the "taste of light" is not a good thing. It is a major flaw. So it is wise to keep your mead protected from sunlight. If light is hitting it during fermentation, that is less likely to be a problem because the fermentation will blow off a lot of sulfur compounds, but during aging and storage, light (esp UV) is not your friend.

I've mentioned this in a couple of other places where this has come up. I apologize for being repetitive, but if any new mead crafters are reading any of these threads later on, they should get the warning.

Medsen

**Yooper** · 12-23-2011, 08:46 PM

Quote:

Originally Posted by MedsenFey

Actually some of it applies. Even if there are no hops, wine and meads contain other compounds such as riboflavin that can interact with UV radiation to produce sulfur odors. This is referred to in France as goût de lumière - but the "taste of light" is not a good thing. It is a major flaw. So it is wise to keep your mead protected from sunlight. If light is hitting it during fermentation, that is less likely to be a problem because the fermentation will blow off a lot of sulfur compounds, but during aging and storage, light (esp UV) is not your friend.

I've mentioned this in a couple of other places where this has come up. I apologize for being repetitive, but if any new mead crafters are reading any of these threads later on, they should get the warning.

Medsen

That's a good reminder.

I've seen lots of posts (especially in the cider forum) where people are assured (incorrectly) that light won't hurt their product, and "only hops cause skunking". While technically true in that it's a different animal (get it? skunk? animal. Nevermind!), it's still possible to ruin a wine/mead/cider by it being light struck.