The other night at dinner I opened a bottle of 2024 Blaauwklippen Sauvignon Blanc from Stellenbosch, South Africa. I’d never tasted the wine before. Within seconds of putting my nose in the glass, I was inundated by the matchstick notes of sulfur, to the extent that I couldn’t smell anything but rubber and the oft-quoted “freshly opened can of tennis balls.”
“Ack,” I said to Carla, “the wine has enough SO2 to stun livestock.”
She frowned, put her nose in the glass, and said, “yeah, the wine smells weird.”
I never knew I was sensitive to sulfur until I went to Germany for the first time in 2000. I was traveling with an importer group that toured the country’s major wine regions for a week, tasting over 200 Rieslings from the just-bottled 1999 vintage. I remember our stop at Schloss Lieser in the Mosel one morning. The wines were brilliant. But halfway through the tasting, I noted that practically all of them had strong sulfury notes. And the only way I could “get” to the wines was by blowing sharply into my glass, which momentarily dissipated the SO2. The ’99 Auslese, in particular, had a lot of sulfur.
I asked Thomas Haag, the winemaker, about it. He replied that his family’s philosophy of winemaking included ensuring the wines could age long-term. Using slightly higher levels of SO2 at bottling was a way of doing just that. To prove his point, he pulled a bottle of 1971 Fritz Haag Brauneberger Juffer Sonnenuhr Spätlese, from his father, Wilhelm Haag’s, cellar. Thomas opened it and poured for the group. The wine still had a pale color and the nose was fresh, belying the fact that it was now 30 years old. So the proof, as they say, was in the bottle. Regardless, the 1999 Schloss Lieser Auslese must have been a “snap” moment for the olfactory center in my brain. After the tasting, I instantly picked up on even a trace of SO2 in any wine. It’s been that way ever since.
A quick word about SO2 before anyone reading this gets dangerously excited. Sulfur dioxide in the form of mined sulfur, which is considered an organic substance by the EU, has been used as an anti-microbial and anti-oxidant in food and wine for over 2,000 years. Added in small amounts, it preserves wine, prevents spoilage in the bottle from bacteria, and also helps prevents oxidation. Is SO2 bad for you? Possibly. If you have severe asthma, you should steer clear. Otherwise, the human body produces a higher level of sulfites every day than the average bottle of wine contains. There’s also far more sulfites in dried fruit, frozen pizza, and other foods. One more thing about SO2. A winemaker once told me that just as we keep our food in refrigerators at home, he used sulfur to make his wines.
However, one can occasionally come across a wine with too much sulfur, as in the South African Sauvignon Blanc. My suspicion with the wine’s issues was that it was bottled using screwcap, the most anaerobic closure other than laboratory glass-on-glass. With a screwcap, the winemaker has to make sure to add just the right micro-amount of oxygen at the time of bottling and to not use too much sulfur. Otherwise, strong off-smelling sulfur compounds called thiol esters can form in the wine that are difficult to eradicate. Per that, I remember a time about 20 years ago when more than a few New Zealand Sauvignon Blancs bottled under screwcap had similar issues with sulfur compounds. The industry has since fine-tuned how much SO2 they use at bottling as well as experimented with different kinds of foils that line the screwcaps.
What’s curious is how sensitivity to sulfur varies with the individual. I would venture a guess that 80% of the population would smell the Sauvignon Blanc we were having with dinner that night and not find anything amiss. A small demographic of people would note that something in the wine was off, while someone who’s sensitive to sulfur like me would jerk their nose out of the glass within a second or two and voice a complaint.
Back to the wine. The sulfury stink persisted. I remedied the situation by heading to the back of the house and nabbing a penny out of the change box on my dresser. Then I took it into the kitchen and rinsed it off thoroughly with soap and water. Finally, I ceremoniously dumped it into my wine glass with a plonk.
“What’s up with the penny?” Carla asked.
I told her sulfur compounds were responsible for the off aromas in the wine and that adding copper in the form of a penny would help get rid of them. In response, Carla gave me the Spock Star Trek skunk eye look.
“That’s the most ridiculous thing I’ve ever heard of,” she said, “putting a penny in a glass of wine.”
“It’s chemistry,” I said. “Here, smell the wine now.”
She did and had to admit that most of the sulfury funk was gone.
“It smells better, but now you have a penny in your wine,” she said. Then she made a show of pretending to take a sip and choking on the penny.
“Hilarious,” I said, and then proceeded to sip on the wine over the next few minutes, with the penny clink-clinking every time I swirled the glass.
After a while, I gave up on the wine, penny and all. But I left the bottle on the counter while I did the dishes to see if it would improve after being open for more than an hour. It didn’t. Then I decided to give it a day or two in the fridge to see if the sulfur compounds dissipated now that there was air in the bottle after half the wine had been poured off. Carla, on the other hand, moved on, saying, “I’m having a gin and finishing the crossword puzzle.”
In the end, I’ll chalk it up to one of the infrequent bottles that had too much added sulfur. But I’ll also quickly note that winemaking globally now is at such a high level that you rarely come across a wine like it. But if it happens, you can always add a penny (a clean one) to your glass. In this case, it’s good for more than just your thoughts.
Learn more professional wine tasting strategies in my book,
Message in the Bottle: A Guide to Tasting Wine
