Coloring options
1.What is the role of colored fruits and vegetables?

Deeply colored fruits and vegetables owe their purple, blue and red hues to anthocyanins. These water-soluble compounds’ coloring effect and stability will shift with pH. In acidic conditions, around pH under 3.8, anthocyanins display rich-red tones. As pH increases, color and stability change, resulting in blue colors with reduced stability.
Grape juice and skins from wine production provide a plentiful, economical source for red-purple colors. Purple sweet-potato juice provides superior stability to light for beverage applications. Anthocyanins extracted from red cabbage and black carrots provide good heat stability, while black-carrot juice offers processors good stability across a greater pH range than most anthocyanins. “One of the most widely used anthocyanin reds is black carrot, which is an excellent choice to color beverages, confections, fruit preparations and dairy yogurts,” says Locey. Other sources of anthocyanins include elderberries, black currants, raspberries, strawberries, cranberries and blueberries.

2.In what conditions that the colors are considered as color additives?

Colors derived from “natural sources” are not exempt from regulation, even though they are natural constituents of foods. In both Europe and the U.S., colors derived from “natural sources” are still subject to existing regulations for color additives. In the U.S., all ingredients deliberately added to food to provide color are considered “color additives,” even if they are derived from natural sources (21CFR§70.3(f) and 201(t)(1) of the Federal Food, Drug and Cosmetic Act (FDCA)). Under Title 21 of the U.S. Code of Federal Regulations (21 CFR)§70.3(g), a material that otherwise meets the definition of color additive can be exempt from that definition on the basis that it is used (or intended to be used) solely for purposes other than as a coloring, as long as the material is used in a way that any color imparted is clearly unimportant insofar as the appearance, value, marketability or consumer acceptability is concerned. Based on these definitions, a substance such as naturally-derived lycopene would be categorized as a color additive if it was added to a food that was not originally red and the lycopene imparted a red color. However, if the lycopene was added for another reason (such as an antioxidant) to a food, such as ketchup, at a level that did not alter the color of ketchup, it would not be regulated as a color additive.