Glutamate - Umami
http://en.wikipedia.org/wiki/Umami
Umami /uːˈmɑːmi/, a savory taste, is one of the five basic tastes, together with sweet, sour, bitter and salty. A loanword from the Japanese (うま味?), umami can be translated "pleasant savory taste". This particular writing was chosen by Professor Kikunae Ikeda from umai (うまい) "delicious" and mi (味) "taste". The kanji 旨味 are used for a more general meaning to describe a food as delicious. The human tongue has receptors for L-glutamate, which is the source of umami flavor. For that reason, scientists consider umami to be distinct from saltiness.
MSG: Is This Silent Killer Lurking in Your Kitchen Cabinets
April 21, 2009
by Dr. Mercola
A widespread and silent killer that’s worse for your health than alcohol, nicotine and many drugs is likely lurking in your kitchen cabinets right now....