Dear Dr. Vinny,
Do Italian wines shipped to the U.S. contain more sulfides than the bottles sold in Italy?
—Linda, Altoona, Pa.
Dear Linda,
I think you mean sulfites, not sulfides, but I thought I’d use this opportunity to talk about the difference between the two. Sulfides are volatile sulfur compounds and, while harmless, are typically considered a flaw because of the stinky, skunky or rotten egg–like aromas they can contribute to wine. Sulfites, on the other hand, are a naturally occurring byproduct of alcoholic fermentation, and sometimes winemakers choose to add additional sulfites during fermentation and at bottling to prevent wine from spoiling.
In the United States, the words “contains sulfites” must appear on the labels of wines with 10 or more parts per million of sulfur dioxide. That’s a pretty low threshold, so most wine labels carry that language. You may have seen bottles sold in Italy that didn’t carry that language, simply because labeling laws differ from country to country. So the same wine—with the same amount of sulfites—may or may not carry that warning, depending on where it is sold. But most Italian wines imported to the U.S. have to have the “contains sulfites” wording on their labels before being sold here.
For most of us, sulfites aren’t a problem, even at levels well above 10 parts per million. They’re in many things we consume, like dried apricots, molasses and blue cheese. But for the approximately 1 percent of people that have sulfite allergies, wine can be a concern. Sulfur allergies can cause some scary reactions, from wheezing and asthma-like attacks to digestive issues and difficulty swallowing. (What sulfites don’t do, however, is cause headaches!)
—Dr. Vinny
Dining and Cooking