Monosodium Glutamate (MSG)—it seems people either love it or hate it. But how can a small white crystal with no distinct taste of its own cause so much controversy?
What is MSG?:
MSG is the salt version of glutamic acid. Glutamic acid is one of a chain of 20 amino acids that make up a protein molecule. It is a non-essential amino acid, which means that the body produces what is needed and we don't need to make it up in our diet. The brain uses glutamic acid as a neurotransmitter.
Glutamate is glutamic acid that has been broken down by fermentation, cooking or other methods. Monosodium glutamate is made by mixing glutamate with salt and water.
History of MSG:
Asian cooks have been taking advantage of glutamate's flavor enhancing properties for centuries. It is unclear whether the Chinese or Japanese first discovered that a broth made from a certain type of seaweed enhanced the natural flavor of food. But it wasn't until 1908 that Professor Ikeda of the University of Tokyo first isolated glutamate from broth made with dried Konbu kelp. (He went on to create and patent Monosodium glutamate, or MSG).
How is MSG Made Today?:
Today, the MSG we find on store shelves is usually made from fermented sugar beet or sugar cane molasses, in a process quite similar to the way soy sauce is made.
Why is MSG So Popular?:
It all comes down to our taste buds. It has long been known that there are four basic tastes—sweet, sour, salty, and bitter. It is now thought that there is a fifth taste, called "umami." Umami is the savory taste that occurs naturally in foods such as tomatoes and ripe cheese. Just as eating chocolate stimulates the sweet taste receptors on our tongue, eating food seasoned with MSG stimulates the glutamate or "umami" receptors on our tongue, enhancing the savory flavor of these foods.
MSG Use in Cooking:
MSG is used extensively in Japanese cooking, where it is sold under the brand name Ajinomoto, and in Chinese restaurant food. MSG use, however, is not confined to Asian cuisine. Ajinomoto is a very popular seasoning in North America, where it is sold under the brand name Accent. Throughout the food industry, MSG is becoming an increasingly popular way to add flavor to packaged foods such as soups, sauces, seasonings, and instant snacks.
What are the Health Concerns?:
Many experts blame MSG for "Chinese Restaurant Syndrome"—the headaches, dizziness, and chest pains some people experience after dining at a Chinese restaurant. There is a debate among the scientific community over whether MSG is the culprit. While the U.S. FDA states that MSG is generally safe, it acknowledges the seasoning may pose problems for certain individuals. Specifically, asthmatics and people who can tolerate small, but not large, amounts of MSG may be at risk.
Should You Use MSG?:
Even if you don't experience negative side effects, is there any need for you to use MSG when preparing Chinese dishes? Again, the experts disagree. Some cooks argue that a well-cooked meal using fresh vegetables doesn't need enhancing. Others do use it occasionally. However, we think we'll leave the last word on the subject to two experts. First, Irene Kuo, author of The Key to Chinese Cooking, considered by many to be the definitive guide to cooking Chinese food:
"While 'taste-essence' is of Chinese heritage, it was never accepted by the elite society of gastronomy where cooking skill and lavish use of natural ingredients are the essence. Today's version is a chemical compound known as monosodium glutamate or MSG and to me it does nothing to enhance flavor. Rather, it gives food a peculiar sweetened taste that I find absolutely distasteful, and for some people, it has unpleasant side effects."
Ken Hom, popular television chef and author of numerous Chinese cookbooks, has a slightly different view: "Scientists still are not sure how this chemical works, but it does seem to bring out the natural salt flavor of foods and can help revive or enliven the taste of bland food and old vegetables...The very best chefs, cooks, and restaurants, however, avoid MSG and rely instead, as they should, on the freshest and finest ingredients that need no enhancing." (From The Taste of China).