Ajinomoto Ajinomoto
Ajinomoto 
Corinthian
17 y
12,290
What is MSG? MSG or monosodium glutamate is the sodium salt of the amino acid glutamic acid. It is often referred to as glutamate as well. Amino acids are the building blocks of protein. Our food and our bodies contain protein that, in turn, contains glutamate. Glutamate is also important to humans for metabolism and brain function, so our bodies even make their own glutamate, about 50 g per day.
Because we make our own supply of glutamate it is called a "non-essential" amino acid by nutritionists. Unlike glutamate, many other amino acids are only available to the human body through dietary sources, these known as "essential" amino acids, but this only from the point of view of nutrition. All the amino acids, including glutamate, are essential to human growth and maintenance. Some have particular functions in the body apart from protein formation, for example glutamate plays a role in metabolism and brain function.
Glutamate is essential to life!
Natural goodness
Glutamate is an amino acid found in abundance in both its "free" and "bound" forms in virtually all natural foods - from meat, poultry, fish, cheese and milk (including human breast milk) to tomatoes, mushrooms and many other vegetables. Glutamate is the most commonly found amino acid in nature, the average diet provides 10 g to 20 g of bound glutamate (bound in protein) and 1 g free glutamate (not bound in protein).
The bound form of glutamate is linked to other amino acids in proteins. Most protein-rich foods contain glutamate, as does the human body. Body tissues - such as your muscles, hair and skin - are largely made of protein.
The glutamate in your body manufactures is essential for protein repair, regeneration and growth. Glutamate also has other essential functions in the body associated with metabolism and brain function. Average-weight adults make 40 - 50g of glutamate daily and their muscles, brain and other body tissues generally contain around 1.5 - 2 kg of glutamate, mainly in bound form.
The free form of glutamate (i.e. not-linked to protein) in foods enhances food flavours. Tomatoes, cheese and mushrooms are just some foods rich in free glutamate long prized for their taste and flavour-enhancing qualities. Free glutamate content increases during natural ripening or maturing of vegetables and of manufactured foods such as cheese and ham, bringing out a fuller taste in many foods.
Meat, fish, cheese and vegetables contain free glutamate:
Modern Asian seasonings, many with ancient roots, impart the umami glutamate taste to foods. These include soy sauce, fish sauce, oyster sauce and numerous other variations. However, the umami taste is not exclusive to Asian foods and ingredients. Anchovy sauce valued in English cookery is also a source of glutamate, adding a savoury richness to a dish. Even the Australian icon Vegemite is rich in glutamate. Other sources of glutamate in foods may be yeast extract, hydrolysed vegetable (or plant) protein (HVP & HPP). These are often added to food for the umami taste.
| |
|
|
mg /100 g |
|
| Anchovy sauce |
630 |
| Vegemite |
1431 |
| Marmite |
1960 |
| Bovril |
498 |
| Oyster sauce |
900 |
| Soy sauce (Japanese-style) |
782 |
| Nam pla (Thai fish sauce) |
950 |
Made from natural ingredients
Many people believe that monosodium glutamate is made from chemicals. Monosodium glutamate is a chemical in the same way that the water we drink and the oxygen we breathe are chemicals. In fact all our food is made of thousands of chemicals. That does not mean they are produced in a laboratory by chemical synthesis they occur naturally. Like many foods glutamate is produced through fermentation, a process used in making beer, vinegar, soy sauce and yogurt. The process begins with natural products such as molasses from sugar cane or sugar beets and food starch from tapioca or cereals which are fermented in a controlled environment with a micro-organism (Corynebacterium glutamicum).
The crude glutamic acid produced in this process is then filtered, purified and converted by neutralisation into monosodium glutamate. After additional purification, crystallisation, drying and sieving, monosodium glutamate has the form of pure white crystals ready for packing and use.
Tasty
Good food is one of life's pleasures and, the better it tastes the more enjoyable the eating experience.
More than 1200 years ago, oriental cooks knew that certain foods tasted better when prepared with a soup stock made from a type of seaweed - Laminaria japonica. But, it was only in 1908 that Japanese scientists identified the component of the seaweed responsible for enhancing flavour. That component is best known today by its scientific name, monosodium glutamate. Commonly called glutamate, it is also often referred to as MSG. The Japanese even have a particular name for the taste of glutamate Umami.
Umami - fifth basic taste
People have long-known about the four basic tastes - sweet, sour, salty and bitter. But now a distinctive, scientifically recognised, fifth basic taste called umami is now universally accepted.
The umami taste is imparted by glutamate in foods. Other substances, including nucleotides, also have the umami taste. However, glutamate is the quintessential source of the umami taste.
Umami is the "savoury" taste we enjoy in tomatoes, cheese, meat, milk, seafood, cheese, mushrooms, peas, broccoli, and other vegetables. It is even found in human breast milk. It can't be reproduced by mixing the other basic tastes. We even have taste buds dedicated to the umami taste discovered in 2000 by researches in the USA at the University of Miami click here for more information.
MSG the first taste
Babies are born with only two sets of taste buds working. Taste buds for sweet to detect the lactose (milk sugar) in their mother's milk and those for umami which pick up the glutamate taste! If breast milk didn't taste good, no baby would want to feed.
Human milk is rich in free glutamate, about 20 times the amount found in cow's milk. So glutamate is one of the first tastes we experience in life, no wonder we think it tastes good!
| |
|
|
mg /100 g |
|
| Humans |
21.6 |
| Chimpanzees |
38.9 |
| Rhesus monkeys |
4.6 |
| Cows |
1.9 |
| Sheep |
1.4 |
| Mice |
2.2 |
In fact glutamate is the most abundant free amino acid found in human milk. There is approximately 4 times more free glutamate than the next most abundant free amino acid, taurine, and 5 times the amount of glycine. The other amino acids are present in much smaller amounts.
Flavour Enhancer
The only purpose to use glutamate in food is to enhance the flavour. It is not a tenderiser or preservative and it is not used to make food look glossy all of these are common misconceptions about glutamate. Glutamate cannot make inferior food taste good.
Added to foods in very small amounts, it brings out the natural umami taste in foods such as soups, sauces and prepared-meals and increases food palatability. Over-use of MSG, or use with poor quality ingredients will result in a poor tasting product.
Many criticise the addition of MSG as a short cut method of enhancing the flavour of food. In this day and age we need as many short cuts as possible; we do not always have time for the long preparation times required to naturally enhance the free glutamate level of foods. The simple addition of the right amount of glutamate, and a very small amount at that, can lift the flavour of a dish. The flavour of a stir-fry dish can be dramatically improved by adding as little as one fifth of a teaspoon of monosodium glutamate.
Like sugar and table salt, monosodium glutamate has no distinctive smell.
MSG and Asian Cuisine
The taste of glutamate is not a modern phenomenon. Greek and Roman civilisations of thousands of years ago used seasonings that were rich in glutamate. Modern Asian seasonings, many with ancient roots, impart the umami glutamate taste to foods. These include soy sauce, fish sauce, oyster sauce and numerous other variations.
It is not only Asian cuisine that has the umami glutamate taste. Italian cuisine, with rich and concentrated tomato sauces and added cheeses such as parmesan can provide even more glutamate than an Asian meal with added monosodium glutamate, so a survey conducted in 1989 by the New South Wales Department of Health discovered. Even the Australian icon Vegemite is rich in glutamate, contributing to its savoury flavour.
Sensory research
An excellent review of the sensory research into the umami taste and glutamate was published in Food Australia by Associate Professor John Prescott of the Sensory Research Science Centre, University of Otago, New Zealand. Ref. 1 Further research conducted into the attitudes to MSG and palatability of foods with and without MSG by the University of Otago (New Zealand)Sensory Research Science Centre was published in Appetite in 2002. This research showed that a negative attitude towards MSG did not result in a prejudice about the flavour enhancement provided by MSG Ref. 9.
Lowering salt and not the flavour in your diet
In an attempt to lower their sodium intake, many people today cut out salt. This is certainly a healthy approach, but the trade-off is often reduced palatability. That's where monosodium glutamate can help it has only one third the amount of sodium as table salt. While not a salt substitute, using just a small amount of monosodium glutamate helps you slash your salt intake by 20-30% without compromising flavour.
Research has shown that people find food with low levels of salt much more acceptable when a small amount of monosodium glutamate is added. The study evaluated people's responses to different versions of a clear soup, with and without MSG and with different levels of salt. The broken horizontal line on the graph shows the threshold level below which the participants in the research found the soup to be unpalatable. Without the addition of MSG, the soup did not become palatable until the salt concentration reached 0.75%. With MSG, however, the soup was palatable with a salt concentration of only 0.4%.
Umami, Saltiness and foods for the aging population
As we grow older, our sense of taste and smell begins to diminish. This process normally begins at about the age of sixty, and becomes more noticeable in our seventies. As a result, elderly people's food choices can change, and sometimes these changes lead to a poorer quality diet or to an inadequate level of food intake. Glutamate can make a helpful contribution to the diet of elderly people by making many foods more appetising and appealing.
Safe
In Australia and New Zealand, no food additive - including monosodium glutamate - is approved for use in food until its safety has been established by Food Standards Australia New Zealand. MSG and other glutamates are among a group of food additives that are generally permitted in foods, due to their recognised safety in their use. (Australia New Zealand Food Standards Code, Standard 1.3.1)
Monosodium glutamate has been on the US Food and Drug Administration (FDA) "Generally Recognised as Safe" (GRAS) list for 40 years. It sits alongside pepper, sugar, vinegar and baking powder. Similar acceptance of the safety of glutamate is reflected in food law right around the world.
Safety affirmed by science
Safety affirmed by science
Monosodium glutamate is one of the most extensively researched ingredients in the food supply, involving literally hundreds of studies in the past 30 years alone. The full body of research has also been reviewed by world leading authorities. Conclusions provide a clear picture of the safety of monosodium glutamate for all ages.
Dispelling the myths
Contrary to common opinion the facts are clear...
MSG is not an allergen
Numerous studies have examined whether monosodium glutamate in food triggers allergic reactions. A position paper issued by the American College of Allergy and Immunology concluded that monosodium glutamate is not an allergen and that severe reactions have nothing to do with this ingredient. Clinical research in the Department of Clinical Immunology and Allergy, Royal Prince Alfred Hospital, Sydney, confirmed that monosodium glutamate is not an allergen. Ref. 4
MSG has no connection with Chinese Restaurant Syndrome
'Chinese Restaurant Syndrome' describes transient discomfort some people feel after ingesting certain foods and beverages. A comprehensive review and strictly controlled study at the University of Western Sydney in 1993 concluded 'Chinese Restaurant Syndrome' is an anecdote applied to a variety of postprandial illnesses; rigorous and realistic scientific evidence linking the syndrome to MSG could not be found. Ref. 5
In 2000 Geha and colleagues published results of a study involving 130 self-reported MSG-sensitive individuals challenged with 5 g of MSG - a very large dose of MSG. (The amount of glutamate added to a prepared meal varies between 0.1 to 0.8%). The researchers concluded that large doses of MSG given without food may elicit more symptoms than a placebo in individuals who believe they react adversely to MSG. However, neither persistent nor serious effects from MSG ingestion were observed, and responses were not consistent on retesting. Ref. 10
MSG does not cause asthma attacks
JECFA also stated that: "Monosodium glutamate has not been shown to provoke bronchoconstriction (narrowing of the bronchial tubes) in asthmatics."
Data from the two most recent studies were presented in 1997 by the Scripps Clinic and Research Foundation in California Ref. 8, and the Alfred Hospital and Monash University Medical School in Melbourne Australia Ref. 6. Both of these studies tested asthmatics who perceived that their symptoms were affected by eating food with MSG. The results of both, which used doses of up to 5 grams of MSG (the equivalent of 3 litres of wonton soup) stated conclusively that MSG does not trigger asthma attacks.
In 2001, one of the authors of the Melbourne study, Dr Rosalie Woods, reviewed all available literature on the alleged link between MSG and asthma and concluded: "Current evidence suggests that the notion of MSG-induced Asthma is extremely rare. Adults with asthma do not need to restrict MSG intake. As it is virtually impossible to avoid MSG altogether, this should ensure that people with asthma enjoy a wide variety of foods and hence consume a diet that is nutritionally adequate. Ref. 1 The Australasian Society of Clinical Immunology and Allergy acknowledges that MSG rarely triggers asthma.
MSG does not cause headache
There are many known 'triggers' for headaches, including diet and stress. A wide range of foods have been implicated as headache triggers. However, a 1990 critical review of the literature on food-triggered headaches (Food triggered migraine: a critical review. Annuls of Behavioural Medicine, 12:51-651, 1990) concluded that the relationship is controversial. The review states that there is no evidence to support an association between MSG and migraine headaches.
Reports that MSG is a vasoactive substance meaning it constricts or dilates blood vessels, thereby producing migraine headache have never been confirmed in a scientifically controlled study. There are many theories about what causes migraine headaches including heredity, neurological brain disorders and blood vessel disorders.
What the experts say
"Several recent reviews of the scientific evidence have confirmed the MSG is safe for the general population at the levels typically found in food." Dr Marion Healy, Chief Scientist, Food Standards Australia New Zealand. Food Standards Newsletter Nov. 2002.
"Glutamate is the most common of the amino acids that make up the proteins in our bodies and in the foods we eat. MSG added to food is identical to the glutamate naturally occurring in food. Natural and added glutamate cannot be distinguished by chemical analysis" Dr Leonid Tarasoff, Former Chair of Chemistry, University of Western Sydney, and MSG Researcher.
"Our study showed that people who believed they reacted to monosodium glutamate were as likely to respond to the placebo (a substance containing no monosodium glutamate) as to monosodium glutamate, although the most common reaction was none at all." Dr Leonid Tarasoff, Former Chair of Chemistry, University of Western Sydney, and MSG Researcher.
"The public perception that MSG causes many adverse effects is certainly not borne out of scientific research well-documented clinical studies have failed to confirm adverse health effects from ingestion of MSG." Associate Professor Connie Katelaris, Head of Allergy Unit, Westmead Hospital.
http://www.msg.org.au/main.html
