A new study demonstrates how Cabernet Sauvignon's larger tannin molecules led to a drier wine.
dry red wine
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Even causal drinkers can usually identify a wine with “big tannins.” Tannins emphasize a wine’s dryness by tingling the side of your mouth or leaving an almost rough feeling on your tongue, a sensation known as astringency. Though the phenomenon is well-known, a new study published in the Journal of Agricultural and Food Chemistry delved deeper into some of the specific physical mechanisms of what makes certain red wines drier than others — and though we may often call tannins “big,” the research points out that drier reds can contain tannins that are literally larger.

The study — which comes courtesy of the Department of Viticulture and Enology at the University of California, Davis, and was supported by the American Vineyard Foundation — began with two different red wines, a Cabernet Sauvignon and a Pinot Noir, with the former being perceived as significantly drier than the latter by a panel of sensory experts. Tannins were extracted from both wines and then analyzed in a number of ways both through physical measurements and further expert tastings. Overall, the paper determined, “The dryness of red wines was related to larger tannins, higher tannin concentration, and a greater turbidity with saliva.”

To confirm these finding through tastings, the researchers added the extracted tannins to a “model wine” made from water, alcohol, and other compounds. Indeed, the Cabernet tannins proved to make the model wine taste drier than when the Pinot compounds were added. However, as a seemingly unexpected result, putting the tannins from one wine into the other didn’t change the perceived dryness of the original wine “probably as a result of the aroma/taste suppression effects and the presence of other components,” the paper suggests.

Regardless, the researchers believe that their study can have a real-life impact in the wine world. The paper concluded, “The results highlight how the dryness perception of red wine can be managed by winemakers based on the knowledge of basic enological composition and wine tannin characteristics.”