Q: Is wine high in potassium?—Ernest, Scotland
A: Our last Health Q&A took a close look at wine’s fiber content and what it could mean for your health. In addition to modest amounts of fiber and a range of potentially healthful polyphenols, wine also contains vitamins and minerals that can play important roles in health. What about potassium?
How Much Potassium Is in Wine?
According to the lab of Dr. Andrew Waterhouse, professor emeritus of enology at the University of California, Davis, the concentration of potassium in wine ranges from 200 mg/L to 2,000 mg/L, and “the high level of potassium in wine is of nutritional significance.”
Generally, red wines contain more potassium than white, rosé and sparkling wines. According to an analysis performed by the United States Department of Agriculture, one 5-ounce serving of Chardonnay contained just over 100 mg of potassium, while a serving of Merlot contained close to 200 mg. For comparison, a medium banana contains around 450 mg.
In the United States, there’s no official recommended dietary allowance for potassium. That said, the National Academy of Medicine’s recommended daily intake is 3,400 mg for adult men and 2,600 mg for adult women.
Why Is Potassium Important for Health?
Potassium is an essential mineral that plays many roles in the body. Crucially, potassium regulates fluid levels inside cells and supports normal heart function. It also plays a role in muscle contraction, kidney health, nerve signaling and more. According to the National Institutes of Health, “the diets of many people in the United States provide less than recommended amounts of potassium.” Many people also consume a lot of sodium relative to potassium, which can contribute to a range of health issues.
How Does Potassium Impact Winemaking?
It’s important for winemakers to pay attention to potassium levels throughout the winemaking process. Grapevines need quite a bit of potassium, and the mineral tends to accumulate in grape skins, so red wines are especially susceptible to high potassium levels. Too much potassium during fermentation and malolactic conversion can increase the pH of the grape must. Potassium raises pH by binding with tartaric acid and causing it to precipitate, thus lowering acidity. This can lead to many problems, including negative impacts on color and intensity, premature oxidation, general instability and even microbial spoilage.
As always, talk to your healthcare provider about incorporating wine into a healthy lifestyle.—Kenny Martin