How many basic tastes do humans have? You were probably taught in school that we have 4 basic tastes: sweet, sour, bitter, and salty.  However, a fifth taste has been known for the last century.  Umami is the fifth taste that was discovered in 1908 by Ikeda.  He noticed that this new taste was present in palatable foods such as fish and meats.  Further research demonstrated that umami is associated with the taste of proteins, more specifically with the taste of aminoacids.   Umami is the characteristic taste imparted by monosodium L-glutamate (MSG) and 5′-ribonucleotides such as disodium 5′-inosinate (IMP) and disodium 5′-guanylate (GMP).  In summary, umami is the name for the “savory” or “delicious” taste that we find in meats, dairy products and mushrooms.

Recent research has confirmed the umami taste by isolating it’s receptor in the human tongue, and that, as with the other basic tastes, certain variability occurs among individuals.  Since Umami is associated with the taste of aminoacids (proteins) an increased understanding of umami receptors may help nutritionists target the protein defficiency in malnourished populations.

If you are interested in reading more details about umami receptors, please refer to:

 American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.2009.27462N
“Perceptual variation in umami taste and polymorphisms in TAS1R taste receptor genes”
Authors: Q.-Y. Chen, S. Alarcon, A. Tharp, O.M. Ahmed, N.L. Estrella, T.A. Greene, J. Rucker, P.A.S. Breslin