Color Indexes: Traditional and Advanced Methods

Color is a relevant wine sensory feature easily perceived by wine consumers and directly associated with its quality. Both red and white wines present the polyphenols as the primary chemical compound responsible for wine color. In red wines, the principal component responsible for their color is the anthocyanin located in the vacuole of the cells in the grape berry skin. On the other hand, the characteristic pale-yellow color in white wines is due to enzymatic reactions affecting polyphenolic compounds such as hydroxycinnamic acids, flavanols, and flavonols, followed by non-enzymatic browning produced by oxidation reactions. Due to the importance of color for wine quality, its management and control are crucial for the wine industry. Usually, wine color is determined using two different spectrophotometric approaches, measurement of color density, and description of color in the CIELAB space, which is detailed in the present chapter. Color density measurement is the most widely used method and is recommended by the International Organiza-tion of Vine and Wine (OIV).