This may have been mentioned earlier. I don't have time to read this
whole string. When I see people grate orange and lemon peel, I get
concerned if the peel looks perfect. These perfect looking fruits are
usually sprayed with coal tar (cancer causing) dyes. They are used
legally here because it's assumed that no one eats the skins of citrus
fruits.

If you're going for flavor, pick orange that were naturally ripened
and have some green and uneveness to the color of the skin, or else
you're eating a paint job.