What’s the Deal with Sulfites in Wine?

sulfites in wine

Who doesn’t love pouring themselves a nice glass of wine at the end of a hard day? The only problem: waking up the next morning with that headachy feeling that so many people attribute to a sulfite allergy. But guess what? Most people actually aren’t allergic to sulfites at all… though that doesn’t mean that sulfites in wine are a welcome addition to cocktail hour.

What Are Sulfites?

Sulfites are compounds that help preserve foods, including wine.

They are naturally occurring in all wines to some extent, as they are a natural byproduct of fermentation. That said, winemakers typically add even more sulfites to wine to stop fermentation at desired times, killing off any bacteria that are present.

Natural wine expert Alice Feiring notes that natural sulfites in wine can be present at anywhere from imperceptible levels to up to 40 parts per million; the legal limits for added sulfites in wine, meanwhile, are between 250 and 260 ppm for white and a bit less for red.

The Sulfite Allergy Myth

Many people claim to be allergic to sulfites, noting that they get headachy after drinking certain wines, but they are often not experiencing a true allergy: there are far more sulfites in dried fruit, for example, than in wine, so unless eating dried apricots makes you symptomatic, what you’re experiencing is not likely a sulfite allergy.

A true sulfite allergy – which is an anaphylactic reaction – is quite rare: less than 1 percent of the population suffers from this life-threatening ailment, according to the FDA.

However, just because you’re not allergic to sulfites doesn’t mean they’re good for you.

“If you’re sitting and drinking two bottles of wine, you’re going to have a hangover anyway,” says Feiring. “But if you’re drinking two bottles of wine without any sulfur added, you’re going to be a little bit less in pain in the morning.”

The reason for this is simple and has to do with the reason for the presence of sulfur in the first place: to kill bacteria.

“What I don’t believe gets enough attention is the fact that sulfites are designed to be toxic,” says James Kornacki, PhD. “When it comes to winemaking, they’re absolutely essential and indispensable, but make no mistake that they’re designed to be toxic, they’re designed to kill things, and that’s because they’re so reactive as chemicals.”

Consuming large quantities of anything that is, for all intents and purposes, toxic, is never a good idea.

“Allergy or not, it’s always your goal to take reactive chemicals, toxic chemicals, out of your diet,” says Kornacki.

It’s for this reason that Kornacki decided to put his chemistry background to good use and invent an object that targets and filters any residual sulfites from wine. He calls the system Ullö, noting that while most filtration systems work like a net, filtering out not only sulfites but other compounds that may have an adverse effect on your wine-drinking experience, Ullö specifically targets sulfites, drawing them away from wine like a magnet.

The Other Problem with Sulfites in Wine

It was during the process of inventing Ullö that Kornacki discovered something surprising: sulfites in wine actually affect its flavor as well, and not in a good way.

“When people refer to sulfites as sulfur, they assume that sulfites would taste kind of like a burnt match, and that’s not the case,” says Kornacki. “They’re a very pharmaceutical, bitter taste, and it lingers in the finish, so we knew if we were removing that, we would change the taste.”

Their removal tends to round out the flavor, he notes, something that even winemakers with whom the Ullö team has worked with can appreciate in their own wines.

But while the Ullö team has managed to filter out sulfites – and only sulfites – some wine experts note that these are not the only detrimental additives in conventional wine.

Alice Feiring has been working and writing at the forefront of the natural wine world for years. She notes that added wood tannins, which fix color in wine, can cause adverse reactions in certain people, not to mention a “a slew of enzymes,” yeasts, or bacteria that are added to jump-start fermentation in wine.

“There are 72 and counting legal additives,” she says. “But I would say that added tannin, which is quite prevalent, and enzymes, those are the two biggest.”

It’s for this reason that she and many others opt for natural wines, a step beyond choosing organic, in this case.

While organic winemakers can and do use additives, as long as they are organic or on the National List, natural wines have no additives at all, and drinking them is a completely different experience from that of drinking conventional wines. Natural wine will have anywhere from no sulfites to 20 parts per million, something that, Feiring notes, changes the flavor of the wine drastically.

“Sulfur acts as a microscope on the flavors of wine, but it also really keeps a lid on it, it keeps it in place, which means that the wine doesn’t evolve very easily,” she says. “And so a lot of people say with conventional wine, the first sip is the best and the last sip is the worst, and in a natural wine, the first sip is not as good as the last sip.”

Natural wines boast a liveliness that conventional wines just don’t, and they’re devoid not only of sulfites, but also of other additives – so you can feel much better about having a second glass.

Related on Organic Authority
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Whole Foods Market to Carry First Sulfite-Free Wines from Italy and Spain
How to Avoid Sulfur Dioxide (and the Startling Reasons Why You Should)

Emily Monaco is a food and culture writer based in Paris. Her work has been featured in the Wall... More about Emily Monaco