I think that I’ve received a journal intended for a now-gone employee. I found The Spectrum journal in my mailbox (Vol. 14, #1). Emblazoned across the front is the lead article: Interplay of Photochemistry and Beer: How Lightstruck Flavor is Formed and How it Can Be Prevented by Denis De Keukeleire of Ghent University in Belgium. Someone either has too much free time, or else Belgium has interesting funding priorities.
As I’ve mentioned elsewhere, I don’t like Beer. I am not a Photochemist. But this article fascinates me. It’s a fully footnoted article about what causes “skunk” beer and what you can do about it.
“The problem of a particular off-flavor in beer exposed to light was recognized as early as in 1875 (3), and simple tests on the protective power of glass indicated that brown bottles were the most effective (4). Gray et al. were first to show that thiols were involved in the development of the offending off-flavor(5).”
There follow eight pages of chemistry. Most of the references seem to be in German.
What’s the upshot? We jump to Conclusions (sorry about that) and find:
“Physical prevention against the lightstruck flavor calls on the use of dark glass bottles (preferably brown-colored) or any opaque package, but modern hop technology enables application of high-tech and efficient chemical protection. Dihydroisohumulones are perfectly light-stable and beers bittered with these advanced hop products can safely be packaged in clear glass bottles.”
Bleaaaghhh!
As I said, I don’t like beer, but this makes me like it even less. Lacing perfectly good beer with a 19-letter chemical from mutant hops just so that you can put it in clear bottles like Zima doesn’t seem to be a worthwhile tradeoff.