Submitted to: Potato Progress
Publication Type: Popular Publication
Publication Acceptance Date: September 25, 2004
Publication Date: October 21, 2004
Citation: Brown, C.R. 2004. Nutrients in potato: carotenoids. Potato Progress. IV(15):3-4. Technical Abstract: Among the natural compounds present in the potato tuber are various carotenoids. There are many types of carotenoids in the plant kingdom. They are important for the animals that eat plants and accumulate in the animal tissues. The red color of shrimp and the pink color of salmon are due to carotenoids that they have obtained originally from marine algae that synthesized them. Carotenoids are generally yellow to red in color. White and yellow flesh potatoes have several types of carotenoids called xanthophylls, and the intensity of yellowness of the flesh is a good predictor of concentration. Two of the most important xanthophylls are lutein and zeaxanthin. Both of these accumulate in the human retina. Lutein and zeaxanthin have been shown to have beneficial affects in the retardation of macular degeneration and cataracts. Lutein and zexanthin have two functions in humans: 1) they serve a light filter, able to absorb energy-rich blue light at the surface of the retina (the macula), and 2) they are antioxidants, capable of scavenging harmful free radicals. It is recommended that 6 to 14 mg of lutein be consumed per day to achieve this kind of therapy. Beta-carotene is a well-known carotenoid which is a precursor to vitamin A. Potato has only traces of beta-carotene. However, the xanthophylls are important in their own right. The white flesh potatoes that are most familiar to the US consumer have between 50 and 100 micrograms per 100 g fresh weight. Yellow flesh potatoes have more carotenoid. For instance, Yukon Gold, a yellow flesh potato that many people in the US have tried, has 194 micrograms per 100 g FW. South American 'Yellow Potato' has up to 2,200 micrograms per hundred grams FW. The potential of developing potato varieties with super high levels of carotenoid therefore exists.