|MadSci Network: Botany|
Apple fruit colors of red and yellow are due to anthocyanins. The green would probably be chlorophyll. Anthocyanins are one of the main pigments responsible for flower, fruit and leaf colors other than green. Anthocyanins are in the cell vacuole, unlike chlorophyll and carotenoids which are in plastids. Anthocyanins have a wide color range depending on pH. A common science project is to use anthocyanins extracted from red or purple cabbage as a pH indicator. Some flowers and fruits, such as orange, eggplant, bell pepper and tomato, and carrot root get their color from carotenoids. References Apple Color and Taste Carotenoids as Flavor & Fragrance Precursors Where does the color come from in purple cabbage?
Try the links in the MadSci Library for more information on Botany.