I accidentally posted this message in "Not about food",
so I am reposting it here. Sorry about that
In the new Scientific American there is an article on the sense of taste. I found it quite interesting.
Two notes: One, the "taste map" of the tongue is apparently just completely wrong; it was based on 18th century research, and keeps getting passed on from textbook to textbook, but has no basis in reality.
Two: The new taste of "unami" is apparently accepted by only a small minority of taste researchers. Most of them (including the authors of the article) stick with the original four tastes.