Monosodium glutamate

Monosodium glutamate, sodium glutamate or E 621 (International Union of Pure and Applied Chemistry name: 2-aminopentanedioic acid,2-aminoglutaric acid,1-aminopropane-1,3-dicarboxylic acid), commonly known as MSG or Vetsin, is a sodium salt of glutamic acid. MSG is a food additive, popularly marketed as a "flavor enhancer". In its pure form it appears as a white crystalline powder; when dissolved in water (or saliva) it rapidly dissociates into free sodium and glutamateions (glutamate is the anionic form of glutamic acid).

Related Topics:
International Union of Pure and Applied Chemistry - Sodium salt - Glutamic acid - Flavor enhancer - Sodium - Glutamate

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

MSG triggers the (recently identified) taste buds which are sensitive to umami, one of the five basic tastes (the word umami is a loanword from Japanese; it is also sometimes referred to as "savoury" or "more-ish"). It is believed that "umami" taste buds respond specifically to certain amino acids (such as Glutamic acid) in the same way that "sweet" taste buds respond to sugars. Some say, however, that MSG simply tricks the brain into believing food tastes better than it does so manufacturers can use less than acceptable ingredients.

Related Topics:
Taste bud - Umami - Basic tastes - Loanword - Japanese

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Glutamic acid is one of the twenty amino acids that make up human proteins; it is critical for proper cell function but not considered an essential nutrient because the body can manufacture it from simpler compounds. In addition to being one of the building blocks in protein synthesis, it is also important in brain function, as an excitatory neurotransmitter. Free glutamate cannot cross a healthy person's blood-brain barrier in appreciable quantities; instead it is converted into L-glutamine, which the brain uses for fuel and protein synthesis.

Related Topics:
Amino acid - Protein synthesis - Neurotransmitter - Blood-brain barrier - Glutamine

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Bound and unbound glutamate are found naturally in nearly every protein-rich food product, including seaweed, tomatoes, mushrooms, fermented soy products, yeast extracts, nuts, legumes, and most meat and dairy products. Yet, despite its ubiquity in common food products, the flavor contributions made by glutamate and other amino acids were only scientifically identified early in the twentieth century.

Related Topics:
Tomato - Mushroom - Yeast extract

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

In 1907, Japanese researcher Kikunae Ikeda of the Tokyo Imperial University identified brown crystals left behind after the evaporation of a large amount of kombu broth as glutamic acid. These crystals, when tasted, reproduced the ineffable but undeniable flavor he detected in many foods, most especially in seaweed. Professor Ikeda termed this flavor ?umami.?

Related Topics:
Kikunae Ikeda - Tokyo Imperial University

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

He then patented a method of mass-producing a crystalline form of glutamic acid, MSG http://www.jpo.go.jp/seido_e/rekishi_e/kikunae_ikeda.htm.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

MSG was first sold commercially under the Ajinomoto ("essence of taste"; 味の素) brand in Japan. Modern commercial MSG is produced by fermentationhttp://www.ajinomoto.com/amino/eng/product.html of starch, sugar beet, sugar cane, or molasses. About 1.5 million metric tons were sold in 2001, with 4% annual growth expected.http://www.ajinomoto.co.jp/ajinomoto/A-Company/company/zaimu/pdf/fact/food_biz.pdf . MSG is used commercially as an inexpensive source of extra flavor, and can be found in many snack foods, frozen dinners, and instant meals such as the seasoning mixtures for instant noodles.

Related Topics:
Ajinomoto - Starch - Sugar beet - Sugar cane - Molasses - 2001

~ ~ ~ ~ ~ ~ ~ ~ ~ ~