Monosodium glutamate, also known as sodium glutamate or MSG, is the sodium salt of glutamic acid

Glutamic acid

Glutamic acid is one of the 20 proteinogenic amino acids, and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salts of glutamic acid are known as glutamates...

, one of the most abundant naturally occurring non-essential

Essential amino acid

An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism , and therefore must be supplied in the diet.-Essentiality vs. conditional essentiality in humans:...

 amino acid

Amino acid

Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...

s.
It has been classified by the U.S. Food and Drug Administration

Food and Drug Administration

The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...

 as generally recognized as safe

Generally recognized as safe

Generally recognized as safe is an American Food and Drug Administration designation that a chemical or substance added to food is considered safe by experts, and so is exempted from the usual Federal Food, Drug, and Cosmetic Act food additive tolerance requirements.-History:On January 1, 1958,...

 (GRAS) and by the European Union as a food additive

Food additive

Food additives are substances added to food to preserve flavor or enhance its taste and appearance.Some additives have been used for centuries; for example, preserving food by pickling , salting, as with bacon, preserving sweets or using sulfur dioxide as in some wines...

. MSG has the HS code 29224220 and the E number

E number

E numbers are number codes for food additives that have been assessed for use within the European Union . They are commonly found on food labels throughout the European Union. Safety assessment and approval are the responsibility of the European Food Safety Authority...

 E621.
The glutamate of MSG confers the same umami

Umami

Umami , popularly referred to as savoriness, is one of the five basic tastes together with sweet, sour, bitter, and salty.-Etymology:Umami is a loanword from the Japanese meaning "pleasant savory taste". This particular writing was chosen by Professor Kikunae Ikeda from umai "delicious" and mi ...

 taste of glutamate from other foods, being chemically identical.
Industrial food manufacturers market and use MSG as a flavor enhancer because it balances, blends and rounds the total perception of other tastes.
Trade names of monosodium glutamate include AJI-NO-MOTO®, Vetsin, and Ac'cent.
A Japanese chemist, Kikunae Ikeda

Kikunae Ikeda

was a Japanese chemist and Tokyo Imperial University professor in Chemistry who, in 1908, uncovered the chemical root behind a taste he named umami. He discovered the common component that produced the flavor of meat, seaweed and tomatoes was glutamate, which produces the sensation of umami.He also...

, noticed that the Japanese broth of katsuobushi

Katsuobushi

is the Japanese name for dried, fermented, and smoked skipjack tuna .Shaved Katsuobushi and dried kelp - kombu - are the main ingredients of dashi, a broth that forms the basis of many soups and sauces in Japanese cuisine.Katsuobushi's distinct umami flavor comes from its high...

 and kombu

Kombu

Kombu or konbu , also called dashima or haidai , is edible kelp from the family Laminariaceae widely eaten in East Asia....

 had a peculiar taste that could not be classified as sweet, salty, sour or bitter.