Name of Japanese origin for the now scientifically recognized fifth taste sensation which is perceived by the presence of glutamate in food or drinks. From a chemical point of view, glutamate is the sodium salt of amino acid Glutamine. Amino acids are the basic building materials for proteins (Proteins). This substance develops flavor enhancing properties in food and plays a special role in the palatability and acceptance of many foods. Glutamate (or glutamic acid) is a building block in almost all proteins, meaning it is consumed with just about any food. Vegetable proteins can even contain up to 40% glutamic acid. But glutamate must not be allowed to gluten (Gluing white) are confused.
Picture left (edited): Copyright: Peter Hermes Furian
Picture right (edited): By NEUROtiker - Own work , CC BY-SA 3.0 , Link
In living cells, glutamic acid is necessary, among other things, for detoxification processes and as an energy source. It is also the most important neurotransmitter for the transmission of stimuli between nerve cells. As taste enhancer only free glutamic acid or its salt works. In food seasonings such as Maggi or Knorr, the relevant proportion is glutamate. Particularly high concentrations of glutamate are found in meat (especially in the raw state such as beef tartare), in human breast milk (22 mg / l), in ripe tomatoes (140 mg / l, in tomato paste four times), in fish, in yeasts, in soy and cheese (in ripened Parmesan even up to 1,200 mg / l). Pure glutamic acid itself tastes sweet and sour and intensifies the taste of salted foods.
The use of these properties has a long tradition in the Far Eastern cuisine. Asian cooks used large-scale extracts over 1,500 years ago seaweed (Species Laminaria japonica) for food preparation. Already in 1908, the Japanese scientist Kikunae Ikeda (1864-1936) discovered that glutamate in protein-rich foods gives a full-bodied taste. He called the taste direction "umami". This means "meaty, hearty and tasty" or is synonymous with "greatest delicacy" or "flavor" and is understood in Japanese for a particularly intense experience of enjoyment. Today, glutamate is used in many foods worldwide and, according to the WHO, has the FDI limit "Not specified". This means that it can be absorbed by humans without restriction. For a long time, glutamate has been named the cause of "China Restaurant Syndrome" with symptoms such as headache and nausea. However, this has not been confirmed in double-blind experiments in any way.
Besides the four traditional taste sensations bitter. salty. angry and sweet 100 years after the discovery of Ikeda in the spring of 2002, umami was proved to be the fifth flavor by the American scientists Charles Zucker and Nick Ryber at the MIT (Massachusetts Institute of Technology) greasy added). Until then, it had been assumed that the sensation was merely a mixed taste of the other four. The receptors (Nerve cells) responsible for the perception of glutamate were found in the taste buds of the tongue. And just as with the other four, there are cells in the brain that explicitly receive and play umami.
As in the Wine Amino acids are included, umami could also be detected objectively in the presence. The problem is that, according to the above studies, the receptors on the tongue are poorly formed compared to the receiving sites in the brain (1 to 100). A phenomenon is that glutamate in combination with a bitter-containing wine, as for example in Barrique If this is the case, the bitter effect is intensified. This can be done, for example, by indulging in Parmesan or smoked salmon, to which an in Oak barrels made wine, is the case. See also below taste and odor,