Wine color

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Judging color is the first step in tasting a wine.

The color of wine is one of the most easily recognizable characteristics of wines. Color is also an element in wine tasting since heavy wines generally have a deeper color. The accessory traditionally used to judge the wine color was the tastevin, a shallow cup allowing one to see the color of the liquid in the dim light of a cellar. The color is an element in the classification of wines.

Color origins

Four glasses of wine (from left to right): white, red, rosé and aged port wine

The color of the wine mainly depends on the color of the

Rubired
to intensify redness.

Red drupe grapes can produce white wine if they are quickly

browning of the wine, leading from red to a more tawny color. The use of a wooden barrel (generally oak
barrels) in aging also affects the color of the wine.

The color of a wine can be partly due to

co-pigmentation of anthocyanidins with other non-pigmented flavonoids or natural phenols (cofactors or "copigments").[1]

Rosé wine is commonly made by the practice of short maceration (exposing wine to red grape skins for only a short period of time in order to give it a lighter feel closer to that of white wine) or by blending a white wine with a red wine.

Color evolution

The presence of a complex mixture of anthocyanins and procyanidins can increase the stability of color in wine.[2]

As it ages, the wine undergoes chemical autoxidation reactions involving

bleaching.[3] The new compounds include pyranoanthocyanins like vitisins (A and B), pinotins and portosins and other polymeric derived pigments.[4][5][6][7]

malvidin-3O-glucoside. When the pH was increased from 2.2 to 5.5, the solution of the pigment became progressively more violet (λmax = 560 nm at pH 5.5), whereas similar solutions of the anthocyanin were almost colorless at pH 4.0.[11]

The exposure of wine to oxygen in limited quantities can be beneficial to the wine. It affects color.[12]

Castavinols are another class of colorless molecules derived from colored anthocyanin pigments.

Structure of compound NJ2, a xanthylium pigment found in wine

In model solutions, colorless compounds, such as catechin, can give rise to new types of pigments. The first step is the formation of colorless dimeric compounds consisting of two flavanol units linked by carboxy-

methine bridge. This is followed by the formation of xanthylium salt yellowish pigments and their ethylesters, resulting from the dehydration of the colorless dimers, followed by an oxidation process. The loss of a water molecule takes place between two A ring hydroxyl groups of the colorless dimers.[13]

Colors

The main colors of wine are:

Other:

  • Burgundy (color), a shade of purplish red
  • Sangria (color), a color that resembles Sangría wine
  • Ox blood, probably referring to ancient practice of fining red wines with dry powdered blood

Scientific color determination

The

Lab color space.[14]

See also

References

External links