Wine can also be categorized by its color. Red wines are produced when the skins of dark grapes are left in the mixture of fermenting juice. The depth of color desired determines how long the skins remain before they are removed. The time period can range from two days to several weeks. If dark grapes are used, the skins must be removed before the grapes are pressed for their juice.
Wines are determined to be sweet, medium or dry based on comparison to other wines.
A sweet wine is said to have a dulcet flavor - which simply means sweet to the taste, while a wine is characterized as dry when it has no taste of sweetness. Medium is somewhere between the two extremes. Although the absence of sweetness typifies a dry wine, they are never referred to as sour. In the wine lexicon, sour means a wine that has somehow gone bad. Certain types of wine and food are traditionally considered to complement each other.