Article: Light-strike taint in wines

Very interesting short article in WFW about goût de lumière and how Champagne and sparkling wines bottled in clear glass are most vulnerable. Action plans are proffered for winemakers, the on- & off-trade, and costumers.

There was a thread about this a while ago.

Somehow I don’t know that I’ve ever experienced it.

Interesting article and more detail than I recall seeing about this. I don’t drink much rosé but I drink a lot of Champagne. Even when drinking Champagne outside in the sun, I don’t recall coming across any of the listed flaws:

dimethyl disulfide or DMDS (onions, cooked cabbage), dimethyl sulfide or DMS (stale cabbage), hydrogen sulfide or H2S (rotten eggs), methanethiol or MT (halitosis, stagnant water), and ethyl methyl sulfide or EMS (wet wool). Initially the smell can be just off or not clean, but put all these compounds together and they will build into the smell of rotting flesh and sewage. Light may also bleach or yellow the color of a wine and degrade the fruity aromas of esters.

I’ve had struck match which blows off. And sherry, nutty, oxidized notes. And, rarely, TCA.But of the above, maybe only suppressed fruity aromas?

It would be helpful to do a side by side of an intact and light-struck bottle. The only wine I have in clear bottles is Cristal, and I’m not leaving one under fluorescent lights for a few days to experiment.

This might call for the purchase of a couple of bottles of inexpensive rosé in clear glass. Any recommendations?

Sounds like a Smörgåsbord of natural wine faults.

Perhaps this is why Crisal comes wrapped?

I’ve had such wines every now and then and the result can certainly be a rather skunky and unpleasant wine. It can also strike your wine sitting in the glass at your porch, which is why I really don’t like drinking fine wines in the sun outside.

It seems to affect wines quite differently. For example I’ve had more lightstruck Chateau Musar’s rosés than I’ve had clean ones, but when I was once sent two sample bottles of some Argentinian rosé wine in clear bottles, I left one to sit on a windowsill for couple of months in the summer and kept the other one in the fridge, yet the difference after two whole months of sun was surprisingly little, the “sunned” wine being only slightly more pale and developed in color with a slightly duller, smokier nose.

It’s precisely because of this.

When I sold specialty wine bottles from France, the dead leaf tint started to get darker. At first they said it was to protect the wine from gout de lumiere.

Later they admitted they had to use more recycled glass.

Supposedly it s higher pH beers in clear glass that risk damage.

Would LED lights be more wine friendly? Some in the lighting business have stated that LEDs do not produce UV radiation. However studies have shown that standard LEDs do create a small amount of UV (Not different from incandescent lightbulbs). But, I have also read that in some very special cases, light from LEDs can be harmful to the eye. This very sharp light is normally filtered away during production, but a faulty LED bulb may be too strong. I am thinking about wine shops etc. with shelves hit with direct light for a time. Otto’s Argentine rosés would do fine, but how about other wines. I agree with Greg regarding my tasting experience with light-struck wines. However, I might have attributed the wine fault to other culprits than the goût de lumière.

All LEDs produce UV radiation. To a very small degree, for sure, but for example when the local alcohol monopoly started using illuminating UV strings fitted into the shelves, I remember how complaints on skunky beers started to increase a little bit. I guess it a very short distance the UV emitted by a LED can be comparable to the amount received from sunlight, at least over a prolonged period of time.

I a couple of weeks ago had a discussion with an employe at the local Norwegian monopoly regarding a bottle of J.B. Becker Rauenthaler Wülfen Riesling Auslese 1989. It was on the top shelf with a LED light glaring right at it. I asked for how long the wine had been exposed to direct light and if they had the same wine back in storage. No purchase was made when the only wines available where on the shelf and the employee assumed since a month ago. I thought it was too risky.

The problem is with clear bottles that don’t block much or any UV light.

LEDs are so weak in UV emissions that most likely a green bottle will block most if not all UV light, purchasing such a bottle is definitely not risky, at least lightstrike-wise. I’d be more worried on how long the wine has been in room temperature. For example we had for the longest time in our monopoly shop a few bottles of Clape Cornas 2014 under average market prices (one of the rare instances of such things happening here in Finland) but knowing how they had been sitting there vertically in room temperature for 4-5-ish years, there was no reason whatsoever for me to even think about buying them.

LED, incandescent, and properly functioning fluorescent and CFL bulbs all give off much less UV than the sun, most or all of it in the less-energetic UVA spectrum. Fluorescents apparently emit more UV than incandescents or LEDs.

I’ll use a CFL for my experiment, and a couple of bottles of Miraval rosé. If I leave the test bottle exposed 24 hours a day, how long should it take to cause noticeable damage? Or should I buy a UVB bulb to speed things up?

Bad news- Wife left the cellar lights on for at least a day or two last week.
Good news- they are LED and not directly pointed at any bottles- all the lighting is indirect.
Good news 2- I have very few clear bottles.

I’d be curious to see results of testing for LED just the same.

The bottle in question was in dark brown glass. And, from what I can glean from this discussion I was probably over-anxious. Storage conditions are also a challenge in the Norwegian monopoly shops. Even though most of them have a walk in temperature controlled room for the more expensive wines.

I’ve been drinking champagnes since 1978 and have never experienced this.

Perhaps this has been covered, but I’ve searched the threads and have not found what I’m looking for.

What is happening to wines stored in glass cellars that are exposed to natural light? These seem to be trendy solutions for wine walls and wine cabinets. I’ve read that the problem isn’t so much the light but exposure to UV rays, yet I combed the science journals and couldn’t find anything conclusive about improvements in UV-blocking films and the impact on wine. It seems if light strike can happen in a relatively short span of time, this is something we would have answers to by now?

Are glass wine cellars with the latest in UV-blocking film acceptable for storing and aging wines?

Many of these are mercaptans, caused when a reductive wine goes one step further and gets ‘reduced’. Very difficult to get rid of these - this is also the reason most reds are not aged in stainless steel unless they are racked often or micro ox is used to reduce the risk of these being developed.

Cheers

I don’t know, but I would definitely not take the chance.