The Scientific Reason Aged Wines Often Taste Better
Aged wines are a balance between four major characteristics: tannin, acid, sugar and alcohol. The presence of any of these variables will help keep the wine longer. According wine madness, acidity helps keep wine lively, tannin gives structure to its flavor and color, sugar works as an excellent preservative (just look at all of our favorite jellies and jams), and higher alcohol ( found in fortified wines) can be used to preserve as well. Any of these in large amounts will aid in the aging of wine, and when combined will cause a chemical reaction that can affect the taste, color, mouthfeel, and smell of wine (via CellaRaiders).
The wine continues to evolve once out of the barrel and in the bottle. Tannins accumulated from contact with grape skins, seeds and stems combine with other chemical molecules, generating more complex aroma and flavor in wine, reports Wired. When a wine is young, the tannins release a bitter and astringent taste and leave the mouth dry. As a wine ages, however, the tannins soften as they polymerize – or chain together – and taste less aggressive while retaining a solid structure for the wine’s flavor and color. (via by Tyrrell).
The wine will become less rich in tannins as it ages. The acidity will remain, but will become more refined and allow softer and more elegant elements to shine through. Giving your wine time to age will ensure that you don’t end up with a mouthful of immature, green, harsh flavors that don’t accurately reflect the true quality of the wine.