Why does red wine become lighter in color as it ages, but white wine become darker?
Why does red wine become lighter in color as it ages, but white wine become darker?
ANS:BY volker stuck
Color maturation in wines is just one small aspect of a very complicated chemical process. When red wines age they gradually turn from a deep purple color to a light brick red. Red wines are kept in contact with the grape skins throughout fermentation. During this process, blue/red-colored phenolic compounds called anthocyanins leach from the skins into the wine. As the wine ages, small amounts of oxygen react with anthocyanins and other, mostly colorless, phenolic compounds, causing them to polymerize and form pigmented tannins. Over time, these produce the brick-red color. Often tannin complexes grow as they react with other wine constituents, such as proteins, and many become too large to stay in solution and precipitate out, leading to the sediment you may find in aged wines. White wines start out in bottles with a greenish tinge (young wines in Portugal are called vinho verde) and end up with a browner hue. White wines are not fermentht Ted with the grape skins, so they contain vastly lower levels of phenols, and therefore tannins. Also, white grapes do not contain anthocyanins—otherwise they would not be white. Consequently those few tannins found in whites are nonpigmented. It is presumed that white wines become browner with age because of the slow oxidation of what few phenols are present. A similar process can be observed in the discoloration of a half-eaten apple. One interesting side note is that anthocyanins are only found in the skins, so it is possible to make white wine from red grapes if the skins are removed. White zinfandel, common in the United States, is an example of this.
ANS:BY volker stuck
Color maturation in wines is just one small aspect of a very complicated chemical process. When red wines age they gradually turn from a deep purple color to a light brick red. Red wines are kept in contact with the grape skins throughout fermentation. During this process, blue/red-colored phenolic compounds called anthocyanins leach from the skins into the wine. As the wine ages, small amounts of oxygen react with anthocyanins and other, mostly colorless, phenolic compounds, causing them to polymerize and form pigmented tannins. Over time, these produce the brick-red color. Often tannin complexes grow as they react with other wine constituents, such as proteins, and many become too large to stay in solution and precipitate out, leading to the sediment you may find in aged wines. White wines start out in bottles with a greenish tinge (young wines in Portugal are called vinho verde) and end up with a browner hue. White wines are not fermentht Ted with the grape skins, so they contain vastly lower levels of phenols, and therefore tannins. Also, white grapes do not contain anthocyanins—otherwise they would not be white. Consequently those few tannins found in whites are nonpigmented. It is presumed that white wines become browner with age because of the slow oxidation of what few phenols are present. A similar process can be observed in the discoloration of a half-eaten apple. One interesting side note is that anthocyanins are only found in the skins, so it is possible to make white wine from red grapes if the skins are removed. White zinfandel, common in the United States, is an example of this.
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