Despite its use as a common flavour enhancer in many types of food, monosodium glutamate has been the focus of several campaigns in recent years that claim the substance can cause unwanted physical symptoms such as migraines, nausea and drowsiness. But the much-maligned MSG is actually a “gem” of a food ingredient, argues Michael Fitzpatrick.

Food lovers might be surprised to discover that MSG (monosodium glutamate) is apparently not bad for you, unless you suffer from asthma or are sensitive to glutamates, and that there is no scientific data to support ‘Chinese Restaurant Syndrome’.
In fact, according to some experts the much-maligned substance is positively a small gem of a food ingredient that should have stuck with its original posh sounding Japanese name ‘Umami’ and the chattering classes would be ooing and ahhing over its quiet extraordinary flavouring properties instead of disdaining it. Just ask the man who has been voted Best chef in the Best Restaurant in the World recently – Heston Blumenthal at the UK’s Fat Duck restaurant in Bray, where he keeps a jar of the stuff in his taste lab.

Blumenthal, like others before him, became interested in MSG when he heard it was invented in Japan nearly a hundred years ago when scientists were trying to recreate what for them was, and still is, the defining taste of Japanese cuisine. Not one of the usual four tastes – sweet, sour, salt and bitter – but a fifth element known as Umami (in Japan derived from the word for delicious, ‘umai’).

Short cut

Only recently recognised in Britain and America, the understanding of Umami is helping reshape our appreciation of food and helping food manufacturers convince customers that MSG or the E number it is sometimes given is not at all bad.

As chef and food chemistry expert Harold McGee recently told the BBC Food Programme, the only real bad side of MSG is that the industry uses too much of it to create flavour where it should be using real food ingredients to do the same job.

“From hypothesis to fact the general conclusion is most of us don’t react to MSG,” he said. “Food companies put too much; making MSG a short cut that been overused. But it is safe.”

His views are backed by a study published in the Journal of Nutrition in 2000 by Ronald Walker and John R. Lupien. In The Safety Evaluation of Monosodium Glutamate Ronald Walker of the School of Biological Sciences at the University of Surrey wrote:

“Conventional toxicity studies using dietary administration of MSG in several species did not reveal any specific toxic or carcinogenic effects.

Because human studies failed to confirm an involvement of MSG in “Chinese Restaurant Syndrome” or other idiosyncratic intolerance, the JECFA allocated an “acceptable daily intake (ADI) not specified” to glutamic acid and its salts. The Scientific Committee for Food (SCF) of the European Commission reached a similar evaluation in 1991.”

Increasing appetite

In its 1995 report to the USA’s FDA, following a comprehensive review of monosodium glutamate scientific literature, the Federation of American Societies for Experimental Biology (FASEB) concluded that there is no difference between the naturally occurring free glutamate found in mushrooms, cheese and tomatoes and the manufactured free glutamate found in MSG, hydrolyzed proteins and soy sauce. The report concluded that monosodium glutamate is safe for the general population.

Now research into umami is proving useful to the food industry, enabling it to produce more delicious functional foods for those, such as old people in hospitals, who need to eat more.

“They will, using MSG and umami flavours, be able, from a sensory point of view, eat better and eat better nutritionally,” says McGee.

Susan Schiffman of the Department of Psychiatry, Duke University Medical Center, Durham, NC, also writing in the Journal of Nutrition under the title Intensification of Sensory Properties of Foods for the Elderly, agrees:

“Taste and smell losses in the elderly can reduce appetite and lead to inadequate dietary intake. One method for “treatment” of chemosensory losses involves sensory enhancement of foods with flavours and monosodium glutamate (MSG). Amplification of flavour and taste can improve food palatability and acceptance, increase salivary flow and immunity, and reduce oral complaints in both sick and healthy elderly.”

The fifth taste category

June’s Cheltenham Science Festival, where chefs and scientists explored the so-called fifth dimension that is umami, it was agreed that amino acid-based taste was gaining acceptance as a fifth true taste category all over the world.

Chefs and scientists alike agreed that umami has hit that elusive quality of deeply savoury food on the head because it didn’t fit into the accepted four categories.

However it is not the first time the west has agreed there are more than four basic tastes. Aristotle identified seven basic tastes: sweet, salty, sour, bitter, spicy, astringent, and sandy, while as early as 1000 B.C., the Chinese documented five basic tastes whereas Indian yogic principles identifies eight.

But it was Japan’s cuisine, rich in umami tastes – soy sauce, seaweed, and so on – that led to the first isolation of the umami elements and the first attempt to synthesize it.

At the beginning of the twentieth century, Professor Kikunae Ikeda of Tokyo Imperial University was thinking about the taste of food: “There is a taste which is common to asparagus, tomatoes, cheese and meat but which is not one of the four well-known tastes of sweet, sour, bitter and salty,” he wrote.

Distinctive taste

A few years later in 1907 Professor Ikeda started his experiments to identify what the source of this distinctive taste was. He knew that it was present in the “broth” made from kombu (kelp seaweed). Starting with a tremendous quantity of kombu broth, he succeeded in extracting crystals of glutamic acid (or glutamate). Glutamate is an amino acid, and is a building block of protein. The Professor found that glutamate had a distinctive taste, different from sweet, sour, bitter and salty, and he named it “umami”. 100 grams of dried kombu contain about 1 gram of glutamate.

The next step was to make a seasoning using his newly isolated glutamate. To be used as seasoning, glutamate had to have some of the same physical characteristics that are found, for example, in sugar and salt: it had to be easily soluble in water but neither absorb humidity nor solidify. Professor Ikeda found that MSG had good storage properties and a strong umami or savoury taste. It turned out to be an ideal seasoning.

Ever since, for instant ‘umami’, MSG has been hard to beat. Harder still though to cut through the bad reputation of the synthetic flavour enhancer? We will have to wait and see.