All About Monosodium Glutamate (MSG) in the Food Industry

Pretty controversial for a food additive. The reactions to it are all over the dial. Patrons object to MSG in restaurant food, then go home and make a soup with chicken bullion just loaded with MSG and think nothing of it.

Oriental food has traditionally been associated with MSG, which is unfair because use of monosodium glutamate is pretty evenly distributed across cuisines of all ethnic origins. The restaurant trade seems to always be collectively pondering whether to use it or not.

In spite of its ubiquity in common food products, the flavor contributions made by MSG were only scientifically identified early in the twentieth century. In the year 1907, a Japanese researcher at the Tokyo Imperial University, name of Kikunae Ikeda, identified some brown crystals that were left behind after the evaporation of a large bowl of broth. He recognized the substance as glutamic acid. These crystals, when tasted, reproduced the flavor he detected in many foods, most particularly in seaweed. Professor Ikeda named this flavor "umami." He then patented the method of mass-producing a crystalline form of glutamic acid, now known as MSG.

The Ajinomoto company was formed to manufacture and market MSG in Japan, and a rough translation of the name "Ajinomoto" means "essence of taste". It was introduced to the United States in 1947 as Accent flavor enhancer. Modern commercial MSG is produced by the fermentation of starch, using sugar beets, sugar cane, or molasses. Almost 1.5 million metric tons of MSG is sold in the United States per year.

Contrary to the stereotype of oriental food, the average American is more likely to encounter MSG in such staples as most canned soups (especially the low-sodium varieties), most beef and chicken stocks and bullion, most flavored potato chip products, many other snack foods such as crackers or cookies, many frozen dinners (especially those which include gravy), and instant meals such as the seasoning mixtures for instant 'ramen' noodles.

In 1959, the Food and Drug Administration classified MSG as a "generally recognized as safe" substance. This action stemmed from the 1958 Food Additives Amendment to the Federal Food, Drug, and Cosmetic Act, which required approval for new food additives prior to their marketing and led the FDA to promulgate regulations listing substances which have a history of safe use, such as MSG. Since 1970, the FDA has sponsored extensive reviews on the safety of MSG, other glutamates and hydrolyzed proteins, as part of an ongoing review of safety data on approved substances used in processed foods.

One of these reviews was by FASEB, the Federation of American Societies for Experimental Biology on approved substances. In 1980, the committee concluded that MSG was safe at current levels of use but recommended additional evaluation to determine the effects of MSG at significantly higher levels of consumption. In 1986, the FDA's Advisory Committee on Hypersensitivity to Food Constituents concluded that MSG poses no threat to the general public but that reactions of brief duration might occur in some people.

These brief reactions are the MSG syndrome you've heard about. When reading about MSG symptom complex, it is essential to keep a couple of things in mind. One, that MSG is a naturally occurring substance; if you've had seaweed, for instance, you've had everything in MSG. Two, small groups of people are allergic to all kinds of common foods, such as berries, gluten, or milk, and apparently MSG is one of those things people are sometimes naturally intolerant of; there is nothing particularly toxic about MSG that makes it more dangerous than, say, table salt.

The symptoms of MSG complex may be any of:
* numbness or a burning sensation in the back of the neck, forearms and chest,
* tingling, warmth and weakness in the face, temples, upper back, neck and arms
* facial pressure or tightness
* chest pain
* headache
* nausea
* rapid heartbeat
* difficult breathing
* drowsiness
* weakness

These may be more or less acute in the presence of other conditions such as asthma, arthritis, or epilepsy. Also, the severity of symptoms may be masked or enhanced by reactions to salt or alcohol. The dosage required to bring these symptoms out is usually around 3 grams - by contrast, the average meal contains 0.5 grams, so MSG is usually brought about by consuming large quantities of it quickly in the form of a soup or gravy. No fatalities have ever been reported in connection with MSG.

The symptom complex happens within one hour after the meal and wears off ofter twenty minutes. It has been suggested that the association with Chinese food comes as much from the salt and grease in certain dishes as from the MSG, and also ingredients like bamboo sprouts contain a high concentration of cyanic acid, which may also be giving people a reaction.

Generally the most common symptom reported is a slight headache. There may or may not actually be a complex of symptoms which are directly the fault of monosodium glutamate, but it is quite clear in any case that the initial media attention to MSG was a typical media panic which blew the reaction out of proportion. A similar "scare" occurred in the 1980's, when the media reported alar on apples. This is not to say that it's "all in people's heads"; there is some evidence which suggests that the syndrome is real, but no clear-cut proof.

But you have to wonder at a substance which has been in every bag of chips sold and consumed in the United States for 20 years with no ill effects reported suddenly producing a severe reaction from a prepared dish at a restaurant. Just something to consider - even the human body contains some amount of MSG naturally!

The bottom line: If you run a restaurant or other food service and you add MSG to your products, clearly say so the same way you would warn people who were lactose-intolerant about dairy additives. While MSG does indeed have its own taste receptors on the human tongue, it's not like leaving it out if requested will kill the whole meal.