Umami

Umami (/uˈmɑːmi/), or savory taste, is one of the five basic tastes (together with sweetness, sourness, bitterness, and saltiness). It has been described as brothy or meaty.

A loanword from the Japanese (うま味^?), umami can be translated as "pleasant savory taste". This was coined in 1908 by Japanese chemist Kikunae Ikeda from a nominalization of umai (うまい) "delicious". The compound 旨味 (with mi (味) "taste") is used for a more general sense of a food as delicious.

People taste umami through taste receptors specific to glutamate. Glutamate is widely present in savory foods, such as meat broths and fermented products, and commonly added to some foods in the form of monosodium glutamate (MSG). Since umami has its own receptors rather than arising out of a combination of the traditionally recognized taste receptors, scientists now consider umami to be a distinct taste.

Scientists have debated whether umami was a basic taste since Kikunae Ikeda first proposed its existence in 1908. In 1985, the term umami was recognized as the scientific term to describe the taste of glutamates and nucleotides at the first Umami International Symposium in Hawaii. Umami represents the taste of the amino acid L-glutamate and 5’-ribonucleotides such as guanosine monophosphate (GMP) and inosine monophosphate (IMP). It can be described as a pleasant "brothy" or "meaty" taste with a long lasting, mouthwatering and coating sensation over the tongue. The sensation of umami is due to the detection of the carboxylate anion of glutamate in specialized receptor cells present on the human and other animal tongues. Its effect is to balance taste and round out the overall flavor of a dish. Umami enhances the palatability of a wide variety of foods. Glutamate in acid form (glutamic acid) imparts little umami taste, whereas the salts of glutamic acid, known as glutamates, give the characteristic umami taste due to their ionized state. GMP and IMP amplify the taste intensity of glutamate. Adding salt to the free acids also enhances the umami taste.

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