One easy-to-find food can be used to determine if a solution is acidic or basic— the red cabbage. This vegetable contains a water-soluble pigment called flavin—also found in plums, apple skins, and grapes—which is also called an anthocyanin. If you chop some red cabbage into small pieces, cover them with boiling water, and allow the mixture to sit for about ten minutes, you can use the cabbage juice to discover the pH of a solution. Basic solutions will turn the anthocyanin in the cabbage juice a greenish-yellow, neutral solutions will turn purple, and acidic solutions will turn red.