By Kim Robson:
I, like many people, used to think that monosodium glutamate (MSG) was some horrible chemical substance to avoid. It is the sodium salt of glutamic acid, one of the most abundant naturally occurring non essential amino acids, the building blocks of all proteins. (Glutamates are actually important neurotransmitters in the human brain, playing a key role in learning and memory.) MSG is derived from yeast extracts and beet roots. As a new fan of natural mineral salts, I was intrigued. The U.S. Food and Drug Administration (FDA) classifies MSG as “generally recognized as safe” (GRAS), but the European Union classifies it as a food additive.
MSG is just one of several forms of glutamic acid found in foods, mostly because glutamic acid, being an amino acid, is pervasive in nature. Glutamic acid and its salts are found in a wide variety of food additives, including hydrolyzed vegetable protein, autolyzed yeast, hydrolyzed yeast, yeast extract, soy extracts and protein isolate. These forms must be labeled with these specialized names even though they are unfamiliar to the general public.
In 1908, Kikunae Ikeda of the Tokyo Imperial University first isolated glutamic acid using aqueous extraction and crystallization. This new taste substance came from the seaweed Laminaria japonica, also known as kombu. Ikeda noticed that a Japanese broth of katsuobushi and kombu had a unique taste that had not been scientifically described at the time and differed from sweet, salty, sour, or bitter. He named this new savory taste “umami.”
To verify that glutamate was creating the umami taste, Ikeda studied the taste properties of other glutamate salts such as calcium, potassium, ammonium, and magnesium glutamate. All glutamate salts produced the umami taste but also had a certain metallic note due to other minerals. Among those salts, sodium glutamate was the most palatable, soluble and easy to crystalize.
Professor Ikeda named his invention “monosodium glutamate” and submitted a patent to produce MSG. The first commercial production of MSG began in 1909 and was marketed as “Aji-no-moto,” which means “essence of taste” in English. Food producers like MSG because it balances, blends, and rounds the total perception of other tastes. Trade names of MSG include Acćent, Aji-No-Moto, and Ve-Tsin.
Used in small amounts, MSG can enhance other taste compounds, improving taste overall. MSG mixes well with meat, fish, poultry, many vegetables, sauces, soups, and marinades. But MSG improves flavors only in the right concentration; too much produces an unpleasant bitter note.
MSG is a great alternative for those who need to reduce their sodium intake due to a predisposition to hypertension, heart disease or stroke. The taste of low salt foods improves with MSG even after a 30% salt reduction. The sodium content of MSG is roughly a third (12%) of the amount found in table salt (39%).
During its use as a food seasoning for more than 100 years, extensive studies have been conducted to better understand the benefits and safety of MSG. As mentioned, international and national agencies overseeing the safety of food additives consider MSG safe for human consumption as a flavor enhancer.
In the late 1980s and early 1990s, however, we started hearing about the “Chinese Restaurant Syndrome,” when Robert Ho Man Kwok anecdotally reported symptoms he felt after an American-Chinese meal. Later termed the “MSG symptom complex,” symptoms reportedly include the following:
· Burning sensation in the forearms, chest, and the back of the neck
· Numbness in the back of the neck, radiating to the arms and back
· Tingling, warmth and weakness in the face, temples, upper back, neck, and arms
· Facial pressure or tightness
· Chest pain
· Rapid heartbeat
· Bronchospasm (difficulty breathing) in people with poorly controlled asthma
There are a number of hysterical sounding websites screaming warnings about a vast, industry-controlled coverup about the dangers of MSG. The supposed studies they cite admittedly use large quantities of MSG, eaten plain, on an empty stomach.
On behalf of the FDA, the Federation of American Societies for Experimental Biology (FASEB) compiled a report in 1995 which said that MSG is safe when “eaten at customary levels.” However, there seems to be a subset of otherwise healthy people who respond negatively to MSG when eating more than three grams on an empty stomach.
The report also showed no evidence to suggest a role of glutamate in chronic and debilitating illnesses. A controlled double-blind multi-center clinical trial failed to demonstrate a relationship between MSG symptom complex and the consumption of MSG in individuals who believed they reacted adversely to MSG. No statistical association was demonstrated; there were few responses and even those few were inconsistent. Symptoms were not observed when MSG was given with food.
Most of the world’s MSG is made through bacterial fermentation in a process not unlike that of making vinegar or yogurt. During fermentation, bacteria are cultured with sugar beets, sugar cane, tapioca, or molasses. These bacteria then excrete amino acids into a culture broth from which L-glutamate is isolated. Sodium is added later.
I think MSG has suffered from bad marketing and bad publicity. Monosodium glutamate is just SO chemical-sounding. It needs a sexy name. (This is why, for obvious reasons, rapeseed oil is marketed as “Canola” oil.) Then MSG got a double whammy of bad publicity: a handful of hyper-sensitive souls, plus a boatload of hysterical hypochondriacs overly susceptible to suggestion, plus ill-informed media hype equaled “evil” cooking spice. I think it’s time to shake out that old notion.