How Much Sugar Is in a Glass of Wine? (Published 2017) (2024)

Q. Some wineries add sugar to dry red wines after fermentation so that they taste “smoother” to the American palate. How can I find out how much sugar is in what I am drinking?

A. To find out how much sugar might have been added to a given wine, your best bet may be to contact the producer directly.

Winemakers employ a range of techniques to achieve desired properties and flavor profiles. The addition of sulfites, used as a preservative, must be listed on the label in order to notify individuals who might be allergic, yet more than 60 different additives can legally be used without being disclosed. With regard to sugar, regulations vary by state. In California, for instance, added sugar is not allowed at any point in the winemaking process. There, winemakers may rely on unfermented grape juice to tweak the sweetness.

“Wine is by nature somewhat acidic, and adjustments can help to balance the elements of sweet and sour,” Nancy Light, vice president of communications for Wine Institute, the main advocacy association for the California wine industry, said in an email. “Winemakers are permitted by government regulations to make sweetness adjustments after fermentation to achieve desired wine styles.”

According to the United States Department of Agriculture, a five-ounce glass of red table wine typically contains about 0.9 grams of total sugar, while a glass of chardonnay contains about 1.4 grams. A sweet dessert wine, typically served in a smaller two- to three-ounce glass, contains as much as 7 grams of sugar. Depending on where the wine was made, the total may include added sugar or sugar from unfermented grape juice, along with the sugar that occurs naturally in the grapes.

The 2015 Dietary Guidelines for Americans recommend limiting added sugar intake to no more than 10 percent of daily calories, which is about 12 teaspoons, or 50 grams. The American Heart Association recommends limiting intake even further: no more than six teaspoons (about 25 grams, or 100 calories) per day for women, and no more than nine teaspoons (36 grams, 150 calories) per day for men.

Along with adding sugar for the purpose of sweetening wine, some producers add sugar before or during fermentation in order to achieve a certain alcohol level. This process is called chaptalization, and it is more common in cooler wine regions such as Oregon, where grapes ripen more slowly. Alcoholic fermentation occurs when yeast metabolizes a source of sugar (glucose, sucrose or fructose), turning it into ethanol (alcohol) and carbon dioxide. In beer, the sugar comes from the starch in malted cereal grain, typically barley. In wine, it comes from grape juice. Grapes that are riper have higher sugar levels, but if available grapes are not as ripe, a winemaker may add sugar to aid in fermentation and achieve the desired amount of alcohol.

According to Tom Hogue, a spokesman for the Alcohol and Tobacco Tax and Trade Bureau, wine producers may provide nutritional details about their products on a voluntary basis, so long as they adhere to regulations from the bureau. So, while winemakers are not required to disclose nutritional information on the label, for those who choose to do so — whether for sugar or other ingredients — guidelines apply.