Description
Grape skin extract is a red to purple powder or liquid concentrate
prepared by aqueous extraction of grape marc remaining from the
pressing of grapes to obtain juice. Extraction is effected with water
containing sulfur dioxide. After concentration by vacuum evaporation,
the sugar content is reduced by fermentation; further concentration
removes most of the alcohol. The primary color
components are anthocyanins such as the glucosides of malvidin,
peonidin, petunidin, delphinidin, or cyanidin. Other components
naturally present are sugars, tartrates, malates, tannins, and minerals.
Alcohol or sulfur dioxide may be added. The powder may
contain an added carrier such as maltodextrin, modified starch, or
gum. In acid solution, grape skin extract is red; in neutral to
alkaline solution, it is violet to blue.
The principal color matters are anthocyanin glucosides of anthocyanidins
(2 -phenylbenzopyrylium salts) such as peonidin, malvidin,
delphinidin and petunidin. (See also ANTHOCYANIN(S).).
Grape skin extract is used for coloring still and carbonated drinks
and ades, beverage bases and alcoholic beverages, subject to specified
restrictions.
Uses
Grape Skin Extract is a natural red colorant with a high concentra-
tion of red anthocyanic pigments which provide its physicochemi-
cal properties. these pigments are responsible for the red, purple,
violet, and blue hues of flowers and fruits. it is prepared by aqueous
extraction of the fresh seedless marc remaining after the grapes have
been pressed in the production of grape juice and wine. it contains
the common components of grape juice, but in different propor-
tions. the color depends upon the medium and the ph. in an acid
medium and up to ph 4.5–5.5, the color is violet and becomes blue
at ph 6.5. it has excellent water solubility and fair heat, light, and
chemical stability. it can be used in soft drinks at 0.2–0.4%, and in
candies at 0.5–1.5%.
