The Truth About Monosodium Glutamate

Monosodium glutamate, or MSG, is the sodium salt of the naturally occurring amino acid glutamate, or glutamic acid. Used as a flavor enhancer since its discovery in 1908 by chemist Kikunae Ikeda of Japan, MSG brings out the savory and complex flavors of meats, broths and cheeses. The word used to describe this type of flavor is "umami."

History

The flavor enhancing properties of monosodium glutamate were discovered when Japanese scientist Kikune Ikeda isolated the compound from a kelp-like seaweed called Konbu used in Japanese cooking. Shortly after Ikeda discovered that MSG was responsible for imparting a savory flavor to soups containing Konbu, he patented a process for isolating it, and began to commercially produce it as a food additive under the name "Aji-No-Moto."

As a Food Additive

MSG is useful as a flavor enhancer, because the taste threshold for the substance is 6.5 times lower than the taste threshold for salt. MSG is sold as white crystalline powder. In the United States it has the trade name "Accent," and in Asian supermarkets it's called "Aji-No-Moto." Because MSG contains only 1/3 of the sodium found in table salt, it can be used in the preparation of dishes to reduce sodium content by as much as 30 percent.

Umami Taste

The flavor MSG enhances is one of the basic taste sensations, called "umami." This flavor is best described as the savory taste characteristic of meats and cheeses. Other substances that contribute to the umami taste of these foods are guanylate and inosinate. When MSG is added to food that contains these substances, the umami taste produced by the synergistic effects of these flavor enhancers is six to eight times greater than the effects of MSG alone.

Myths

In the 1960s, reports surfaced blaming MSG for a complex of symptoms known collectively as the "Chinese Restaurant Syndrome." Symptoms of this illness, also called the MSG Symptom Complex, include headache, flushing, facial tightness or pressure, numbness down the neck and spine, heart palpitations, nausea and weakness. However, several scientific studies have since shown that MSG cannot be positively linked to these or other adverse symptoms, which are likely caused by food allergies to other ingredients instead.