Liz Sagues provides her takeaways from the 112th online Circle seminar, in which member Peter Richards MW honed in on what he refers to as the biggest, yet least talked about, wine fault, ending with a pressing call to action.
“Light strike is a scandal and we all need to do something about it. It is the biggest wine fault, yet the least talked about.” With that forthright message, Peter Richards MW began one of the most important presentations in the Circle’s Let’s talk about… online seminars, now numbering 112.
The problem is caused when wine in clear glass bottles is exposed, even briefly, to daylight or artificial light. It’s not a new discovery, recognised in Champagne for half a century, and there has been plenty of research proving its destructive effect. Rosés and whites are obviously most affected, as they’re most often sold in clear bottles. And traditional-method sparkling wine can be particularly badly hit.
Light strike sprang into wide public attention last year when Peter, a Circle member, and his wife and fellow MW Susie Barrie carried out a home experiment and detailed the results on their Wine Blast podcast. There was reaction way beyond the usual wine-oriented audience. Headlines in the national and international press proclaimed the wrecking effect. “The podcast made a bit of a splash,” Peter acknowledged to the Circle online audience.
There are two major outcomes when wine is tainted by light, he continued. In the first the wine is muted, its character gone; in the second thoroughly unpleasant aromas develop, which are often cabbagey. He proved the point again there and then, by immediately identifying from two blind samples of rosé prosecco the one which had been exposed to light.
Packaging is the key, he argued. Dark amber bottles provide the best protection, clear or flint glass ones virtually none at all; the new PET bottles are good, as is bag-in-box. Light strike happens quickly – the major effect is within a week. And it is “irreversible and cumulative”.
Alongside the invitation to attend the Let’s talk about… session members were invited to do their own experiments, with the same wine (previously not exposed to light) decanted into two clear glass bottles, one left in daylight and the other in artificial light for a week, with a control bottle in dark glass kept in a dark place.
Heather Dougherty poured herself glasses of Piedmont Chardonnay – the example exposed to artificial light was flat and without character, the daylight one was starting to head down the brassica route. My light-struck glasses of southern French rosé (from a bag in box) shared an appreciable difference in colour against the control wine, general muting and, for the daylight example a double-yuk comment; the artificial light version was unpleasantly stinky, too. Others attending, notably rosé expert Liz Gabay MW, confirmed their own experiences of light strike.
The podcast has begun to stir action beyond the media headlines, Peter reported. A major producer in Provence and another in Germany are considering changes to their packaging. But there will need to be a major shift to emphasis on quality rather than on marketing. Why, he asked, should rosés need to be so frequently sold in glass bottles when today almost all are a similar pale colour and imaginative, distinctive labelling could provide any necessary point of difference. Broader education on light strike is necessary, too – he instanced the lack of understanding among wine makers and wine students.
But communicators should be involved as well, he concluded. “It’s something we all need to champion. No more sweeping of this issue under the carpet. Never buy wines in clear glass bottles – and don’t recommend them.”
That last instruction is my 2025 (and onwards) resolution. As I write for a non-national publication and can spread the word through only a small number of consumer tastings each year, I doubt that will help much. But if every one of the Circle’s 270 members did the same…
Those who couldn’t attend on February 4th should watch the Let’s talk about… recording: YouTube, and also Peter and Susie’s original podcast. You’ll never again buy a clear glass bottle of rosé from a supermarket shelf.
Main image: Light strike experiment. Photo credit: Susie and Peter