DESCRIPTION

Grape Skin Extract occurs as a red to purple powder or liquid concentrate. It is prepared by aqueous extraction of grape marc remaining from the pressing of grapes to obtain juice. Extraction is effected with water containing sulfur dioxide. During the steeping process, sulfur dioxide is added, and 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. 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 unstable and violet to blue.