Grapes are fruits that grow in clusters of 15 to 300, and can be crimson, black, dark blue, yellow, green, orange, and pink. “White” grapes are actually green in color, and are evolutionarily derived from the purple grape. Mutations in two regulatory genes of white grapes turn off production of anthocyanins, which are responsible for the color of purple grapes.
Raw grapes are 81% water, 18% carbohydrates, 1% protein, and have negligible fat (table). A 100 gram reference amount of raw grapes supplies 69 calories and a moderate amount of vitamin K (14% of the Daily Value), with no other micronutrients in significant content.