By law, every bottle of wine sold in the United States must carry those two unsettling words, contains sulfites. Not only is the phrase a bit ominous, it's also a source of confusion. To sort things out, here are a few answers to some of the most common questions.
• Exactly what are sulfites?
The word sulfites is a catchall term for sulfur in all its various forms. And sulfur has been used as a wine preservative since antiquity. First, it's important to understand that sulfur, an element occurring in the earth's crust, is a natural compound. When this elemental sulfur is burned in the air, it forms sulfur dioxide. Added to wine (usually as a gas), sulfur dioxide acts as an antioxidant, prevents bacterial spoilage, and inhibits the growth of yeasts, effectively keeping wine from turning brown and spoiling.
But here's the most fascinating part: It's impossible to produce a wine that is entirely sulfur-free, because a small amount of sulfur (usually 10 to 20 parts per million) is a natural by-product of fermentation and the metabolic action of yeast. So all foods that are fermented ― bread, cheese, beer ― contain sulfites too.
• Does wine contain a high concentration of sulfites?
In the last decade, winemakers the world over have begun using less and less sulfur. Federal regulations permit up to 350 parts per million in wine; in practice, most wines contain much less than that. Dry white wine, red wine, rosé, and sparkling wine all contain about the same amount of sulfites. Some sweet wines contain a bit more, since they're especially susceptible to bacterial spoilage.
• Are sulfites dangerous?
According to the Harvard Health Letter (June 2002), only a small percentage of people ― an estimated 1 percent ― are allergic to sulfur. They have respiratory reactions to all foods that contain sulfites. (It was to protect these individuals that the "contains sulfites" label on wine was mandated.) Many people, however, blame sulfites for the headache they get after drinking red wine. The truth is, it's not known for sure whether sulfites have anything to do with red-wine headaches (RWHs, as they're called); evidence seems to the contrary, since allergic reactions to sulfur involve respiratory problems, not headaches. Furthermore, sweet wines, which contain higher levels of sulfites than red wine, don't appear to cause headaches. Happily for 99 percent of us, sulfur in wine is considered harmless.
On cold winter evenings, I crave slow-cooked lamb or duck. One of my favorite wines with these rich, earthy meats is Syrah. Here are three delicious partners.
Frog's Leap Syrah 2001 (Napa Valley), $25. Complex, fascinating aromas and flavors of roasted meats, black licorice, dark earth, and exotic spices.
McDowell Valley Syrah 2001 (California), $12. Juicy berries and lots of other ripe fruit, with a gripping finish. Good value.
Zaca Mesa "Black Bear Block" Syrah 1999 (Santa Ynez Valley, CA), $45. Reminiscent of dark chocolate-covered cherries. Luscious and palate-saturating, with notes of vanilla and spice. Hard to resist.