The first and most obvious characteristic of red wine is the color. Red wines range in hue from deep, opaque purple to pale ruby and everything in between. As red wine ages, its bright, youthful colors turn garnet and even brown.
The second characteristic of red wine is tannin. Red wines are made by macerating the juice of grapes with the skins and seeds, and sometimes even the stems as well, which is typically called whole cluster fermentation. All of these elements of the grape bunch impart tannins to the wine.
The third characteristic of red wine is its wide range of flavors. Different grape varieties produce aromas of fruits, flowers, herbs, spices and earthy characteristics. For example, Pinot Noir tends to have raspberry, cherry and forest floor notes, while Cabernet Sauvignon generally boasts notes of cassis, licorice and wet gravel.