One health question that I get more than any other—besides whether or not a wine contains sulfites—is whether or not wine is gluten free. The short answer is that yes, it is. The production of wine is inherently gluten free as the raw materials involved are grapes, and there is no wheat used in the growing or fermentation process.
As far as the production process, the only place—theoretically—where gluten may be used is in fining. The best fining agents are animal based products, the most common being egg whites, but I couldn’t find any winemakers that use wheat gluten in this capacity.
In regard to the aging process, the heads of some wine barrels can be sealed with a wheat paste; however, wax alternatives have been found to be less expensive, and offer a better seal. Tricia Thompson, a dietician who specializes in gluten free products recently commissioned tests of a Cabernet Sauvignon and a Merlot. The results of the tests conducted on both wines came back showing fewer than 10ppm. According to the FDA, products that contain fewer than 20ppm are considered gluten free.
So, to sum up, for all intents and purposes there is no discernible gluten to be found in wine, making those who must or who choose to watch their gluten intake very happy!
*always check with your doctor as the final source of information.