Tannin belongs to tannic acid, which is a plant component with tanning property, and its structure is complex. The main body of tanning effect is polyphenol. Generally, it has astringent taste and can precipitate protein and alkaloids.

Although tannins cause the bitterness of red wine, it is wonderful that after the wine is properly stored in the bottle for a period of time, its strong and rough personality will be transformed into quiet, elegant and smooth throat, so it takes time for good vintage red wine to mature.

shelf life

Red wine is not the older the year, the better. The year on the red wine refers to the year's grapes. Most (99%) wines have no aging ability, and the best drinking period varies with different wines, generally between 2-10 years. Only a few particularly good wines have the ability to age. Some top French and Italian red wines have the ability to age for decades or even hundreds of years. Many wines from Bordeaux's top wineries are still suitable for drinking even if they have been preserved for more than 1 century. Tannin (tannic acid) is needed for wine aging, and Cabernet Sauvignon (grape variety) is the most suitable for aging among many grape varieties because of geographical factors and its characteristics.