Purple sweet potato color is obtained by smashing, aqueous extracting and purificating of purple sweet potato imported from Japan. Its principal constituent is anthocyanin. Purple sweet potato color not only possesses pigmentation function, but also owns health care function, such as cancer prevention, oxidation resistance and free radical elimination. Range of application: It is suitable as coloring materials in food service and beverage industry, such as candy, cake, jam, jelly, and preserved fruit and drinks,. Characteristics: Bright color, light fastness. It should be no harm to human body, no peculiar smell, no pesticide residues and no discolor when sterilized or heated and outstanding heat-resistance. The PH has effects on its color, under acidic condition, the watery solution is purplish-red color and stable, as pH is increased, the watery solution become purplish-blue, purplish-green and finally green. Appearance: powder(E10%1cm,530nm,pH=3,color value 300.