Monosodium
glutamate (MSG) has been used to enhance the flavor of food for more
than 100 years. It was originally synthesized by Japanese biochemist
Kikunae Ikeda in 1908 after he realized that the Japanese broth
called dashi (a basic stock made with seaweed and dried fish) had a
meaty flavor that had not yet been identified. He called this flavor
umami, which can be translated as "delicious taste" and set about
synthesizing the main source of it. The basic sensory function of
MSG is attributed to its ability to enhance savory taste-active
compounds when added in the proper concentration
MSG, which first hit the market in 1909, is today created by
bacterial fermentation in a process similar to that used in making
yogurt.
Monosodium glutamate added to foods produces a flavoring similar to
the glutamate that occurs naturally in foods. It acts as a flavor
enhancer and adds a fifth taste, called umami, which is best
described as a savory, broth-like or meaty taste.
In the European Union, monosodium glutamate is classified as a food
additive (E621) and regulations are in place to determine how and
when it can be added to foods. Typically, monosodium glutamate is
added to savory prepared and processed foods such as frozen foods,
spice mixes, canned and dry soups, salad dressings and meat or
fish-based products. In some countries, it is used as a table-top
seasoning.
Scientific studies have not shown any direct link between monosodium
glutamate and adverse reactions in humans. The US Food and Drug
Administration has given MSG its generally recognized as safe (GRAS)
designation. While a popular belief holds that large doses of MSG
can cause headaches and other feelings of discomfort, in controlled
studies scientists have been unable to consistently trigger
reactions. MSG has been used for more than 100 years to season food,
with a number of studies conducted on its safety. International and
national bodies governing food additives currently consider MSG safe
for human consumption as a flavor enhancer.
MSG contains about one third of the sodium of table salt and is used
in smaller amounts.
Children metabolize glutamate in the same way that adults do and
monosodium glutamate is safe for children. In fact, human breast
milk contains ten times more glutamate than cow’s milk.
When added to food, MSG provides an umami-rich flavor boost that
regular table salt doesn't, even though MSG contains sixty percent
less sodium than table salt, and many people cook with it regularly
(it is sold under the brand name Accent). While it doesn't have much
of a flavor on its own, when added to other foods it blends,
balances, and rounds out the other flavors that are present.
MSG does not occur naturally in whole foods, so you do not have to
worry about it in fruits and vegetables.
The human body also produces glutamate and it plays an essential
role in normal body functioning.