Mangoes and carrots are beautiful to look at because they contain rich deposits of carotene pigments. The carotenes come in many different variations, and range in color from yellow to deep orange. Beta carotene in particular is a valuable nutrient because it's an antioxidant, and because our bodies can convert it into vitamin A, which has important roles in our eyes and in other tissues. So we can count on orange-colored fruits and vegetables to be especially good for us. But often we don't get as much of their goodness as we might think.
Mangoes are a different story. Reinhold Carle and colleagues at Hohenheim University recently studied mango cells and found that they store their carotene pigments not in solid crystals, but in microscopic oil droplets, where they are predissolved and so presumably much more available for our bodies to absorb them, even when we eat the fruit raw.
In a 2003 paper, Carle and colleagues reported that dried mangos are a concentrated source of beta carotene, even though the drying process does destroy some of the pigment. Sun-dried fruit suffer the greatest losses.
Vasquez-Caicedo, A.L. et al., J. Agric. Food Chem. 2006, 54 (16) 5769.