Q: Do red wine polyphenols, especially resveratrol, quercetin and other molecules linked to improved health, affect how a wine tastes?—Bill, Cora, Wyo.
A: Red wine contains many polyphenols, a large class of molecules that have been linked to a range of benefits, from improved cardiovascular health to a reduced risk of certain cancers. Polyphenols are central to any conversation about wine and health, and molecules such as resveratrol and quercetin often make the news. But do they affect how a wine tastes?
Dr. Andrew Waterhouse, emeritus professor of viticulture and enology at the University of California at Davis, told Wine Spectator that generally speaking, polyphenols like resveratrol and quercetin “don’t contribute too much to the taste of wine, largely because the amount is pretty small.” Many polyphenols are bitter, but the average human taste threshold for that bitterness is relatively high. You’d need around ten times the concentration of resveratrol typically found in red wine to begin detecting any bitterness.
Some people, the so-called supertasters among us, have a high concentration of taste buds and are extra sensitive to taste perceptions, especially bitterness. In fact, scientists identify supertasters by their reaction to a bitter compound called 6-n-propylthiouracil (PROP), which is intensely bitter to supertasters but innocuous (or even completely tasteless) to most people.
Unlike other taste perceptions, Dr. Waterhouse says, “with bitterness, there’s a huge variation” in people’s sensory thresholds. While some supertasters may find red wine bitter, for most people, the level of polyphenols in the wine shouldn’t be high enough to cause a bitter taste.
Since polyphenols in red wine generally can’t be tasted, a wine’s taste isn’t necessarily an indication of its potential health benefits. That said, some researchers hypothesize that young, highly concentrated red wines may be best for health due to the potential benefits of tannins, which are themselves a kind of polyphenol.
But how do tannins affect a wine’s taste, and are they actually important for health? Read our next Health Q&A, in two weeks, to find out. And as always, talk to your healthcare provider about incorporating wine into a healthy lifestyle.—Kenny Martin