In the last post about longans, commenter John L. (an esteemed and educated person) inquired about mangosteen. No relation to the mango, this treasured fruit has been dubbed "The Queen of Fruits" (apparently, the odoriferous durian claims the King title) and is indeed difficult to ship outside of the tropics. I've seen and purchased them in frozen form in area Asian markets, and I fear that they lose their distinctive flavor this way. The promise of fresh domestically grown mangosteen was reported in 2006, but I've yet to see the fruit of that promise. The Panoramic Fruit Company founded for this purpose in Puerto Rico simply reports that they are not shipping to the mainland US.
It's a shame. I've had mangosteen in Canada (for a shocking price), but it couldn't be brought back over the border.
Like the pomegranate, one eats the white arils surrounding the seeds (don't bother spitting the seeds out, just swallow them). The main pulp is a beautiful purple color, but isn't really eaten. The flavor is bright, acidic, sweet, ephemeral. It really is its own flavor. Some of the best are grown in Thailand - if you have the opportunity, you should try it.