Beets are among the few red vegetables. They get their color from a group of pigments called anthocyanins. These are the same elements responsible for most of the color in red, purple, and blue fruits and flowers. Extracted beet juice can be used to color food products as an alternative to artificial red dyes. If added to foods that are too alkaline, the color will change from red to purple and begin to fade. Adding an acid will prevent this and will even reverse the effect after it has occurred, changing the purple color back to red.