Lycopene, a carotenoid found in plant foods, is also a red pigment. Dark red acicular crystal. Unstable to light and oxygen, turns brown in the presence of iron. Molecular formula C40H56, relative molecular mass 536.85. The content is higher in the fruits of mature red plants, especially in tomatoes, carrots, watermelon, papaya and guava. It can be used as a pigment in food processing and is also commonly used as a raw material for health food.