I came across an old saying (I would even call it a myth) that vitamins are concentrated under (or close under) the peel of apples or potatoes and other fruit. This implies that they are more healthier when not pealed. My question is: Is this true? And does it make sense to concentrate important substances there, where they might get lost when the peel is damaged?
There are some vitamins in the peel of some fruits/vegetables. The color of many fruits and vegetables is the result of high carotene concentration in the peel. $\beta$-carotene is converted by the human body into retinal, which is a form of vitamin A .
Another example is vitamin C. Guava and citrus category fruits contain high amounts of ascorbic acid in their peel and orange's peel contains greater amounts of vitamin C than its juice .
There are also other compounds in fruits peel like B vitamins and minerals .
This implies that they are more healthier when not pealed.
In most situations, yes. The peel can absorb insecticide sprays and can also contain high amounts of fibers which can cause indigestion . The peel can contain allergens .
And does it make sense to concentrate important substances there, where they might get lost when the peel is damaged?
Yes. For example carotene plays a role in photosynthesis . Fibers improve mechanical properties of the peel, thus protecting the fruit.
- Wikipedia contributors, "Carotene," Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Carotene&oldid=625015773 (accessed September 14, 2014).
- Umesh Rudrappa, www.nutrition-and-you.com. Fruit peel nutrition facts
- Wikipedia contributors, "Peel (fruit)," Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Peel_(fruit)&oldid=624708837 (accessed September 14, 2014).