What does msg allergy look like
Research hasn’t shown MSG to trigger allergy symptoms in large studies, but according to Nish, that doesn’t mean a sensitivity to the ingredient doesn’t exist. “No double-blinded, placebo-controlled studies own shown it to cause problems in a large number of people, [but] I’m certain it can cause this in certain people,” he says.
So if you ponder you’re sensitive to MSG, figure out which foods trigger your symptoms and avoid them.
Kathleen Holtonis a professor in the School of Education, Teaching and Health and the Middle for Behavioral Neuroscience at American Universityin Washington, D.C.
Her research examines the negative effects of food additives on neurological symptoms, as well as the positive, protective effects of certain micronutrients on the brain. She is working on a book about how people can avoid consuming food additives and test themselves for sensitivity.She contributed this article toLive Science’sExpert Voices: Op-Ed & Insights.
A recent videofrom the American Chemical Society purporting to debunk myths about the food additive monosodium glutamate (MSG) led to a slewof news stories — but that coverage failed to recognize that a subset of the populationshouldavoidMSG.
The video contains two misleading facts.
The firstsuggestsMSG is considered «Generally Recognized as Safe,» or GRAS.TheGRAS label for additives gives the appearance of safety; yet the term GRAS was simply given to food additives that were in use when the Food Additives Amendment of was established. The label effectively «grandfathered in» the additives so theycould bypass premarket approval by the FDA (i.e., safety testing). Secondly, the video states that free glutamate occurs naturally in some foods.
This is true; however, it does not mean that MSG is safe for everyone.People who are sensitive to MSG mustalsoavoid foods with high amounts of naturally occurring free glutamate, such as soy sauce and Parmesan cheese.
How MSG works
MSG is a flavor enhancerthat has been used in processed foods in the United States since after World War II. Though numerous associate MSG with Chinese food, people are more likely to encounter MSG in foods love soup, broth, chips, snacks, sauces, salad dressings and seasoning packets. The athletic part of MSG, which imparts its «umami» flavor, comes from the glutamate portion of the compound.
Glutamate is an amino acid commonly found in the diet in bound form (connected to other amino acids to form a full protein, love meat) and free form (where glutamate is no longer bound to a protein). It is this free form of glutamate (like that found in MSG) which has the ability to act as a flavor enhancer in food by exciting the neurons in your tongue.
Glutamate can always be considered a «natural flavor» because it is produced by dissociating a naturally occurring protein into its individual amino acids.Additives containing free glutamate are created by simply disrupting any protein’s structure through hydrolyzation, which frees glutamate (and other amino acids), allowing glutamate to enhance the flavor of food by stimulating the neurons on your tongue.
Who needs to avoid MSG?
As researchers, we don’t yet know what percentage of the population is sensitive to MSG.
But we do know enough to confirm that the amino acid glutamate, when in its free form (i.e., when it is not bound to a full protein love meat) causes negative reactions in certain people. An individual’s reaction to MSG is not limited to Chinese Restaurant Syndrome (CRS), which is characterized by symptoms love headache, sweating, rapid heartbeat and tightness in the chest. These symptoms generally happen within minutes of eating the compound, often while the diner is still in the restaurant.
In my research on the effects of MSGin individuals with irritable bowel syndrome and the chronic pain condition fibromyalgia, I observed headache (including migraine), diarrhea, gastrointestinal pain and bloating, extreme fatigue, muscle pain and cognitive dysfunction — every of which improved when subjects were put on a diet low in free glutamate, and which returned with re-introduction of MSG.
(This was a double-blind, placebo-controlled study). In contrast to CRS, symptoms in fibromyalgia patients tend to beginsomewhat later,hours after ingestion, making it more hard for these people to identify the food-related trigger.
Other researchers are studying the potential effects of MSG on conditions love migraine, temporomandibular joint disorder (TMD/TMJ), obesity and Type 2 diabetes. Researchers from the University of North Carolina at Chapel Hill recently found an association between high consumption of MSG and the prevalence of overweight adults in China.
Understandably, the glutamate industry is hotly contesting these and other findings related to MSG and obesity.Consumers should know that the glutamate industry funded the majority of studies «proving» the safety of MSG. Independent scientists own not always agreed with those findings.
In addition to MSG, free glutamate can also be found in other food additives, including any hydrolyzed protein, protein isolate, protein extract and autolyzed yeast extract, just to name a few.
Food manufacturers can use these additives in a product, and still label the food as not containing MSG, since the chemical structure is diverse. That is, the structure does not contain the sodium part to form monosodiumglutamate. However, the effect of the free glutamate is the same as that of MSG (both in its flavor-enhancing ability as well as its ability to cause symptoms in sensitive individuals).
Glutamate is not only an amino acid in the diet, it is also an significant neurotransmitter essential for the optimal functioning of our nervous systems.
However, too much of this chemical can cause things in our bodies to go awry. It is well established that high amounts of glutamate can cause «excitotoxicity,» where neurons get over-excited to the point that they die.
For example, because of the consistent research on the excitotoxic effects of MSG on the brains of young animals in the s, researchers testified before the U.S. Congress about the harm of using MSG in baby food. As a result, MSG was voluntarily removed from baby foods in
The million-dollar question is: Does everyone react to these additives?
No, some people can consume relatively high amounts of free glutamate without any symptoms.However, research shows that a subset of the population is sensitive and can benefit from avoiding MSG (and other sources of free glutamate) in food.
If a person is suffering from unexplained symptoms love headache, bowel disturbance, fatigue, cognitive dysfunction, or pain that lacks a structural explanation, they may desire to attempt avoiding free glutamate in every its forms. The only way to test for sensitivity is by avoiding excess free glutamate for a period ranging from two weeks to a month. One can do this by eating whole, non-processed foods, using whole herbs and spices, making marinades and salad dressings from scratch, and avoiding foods which naturally own higher amounts of free glutamate, love soy sauce, fish sauces, Parmesan and other aged cheeses, and large amounts of tomato sauce.
The moral of the tale is simple: Blanket statements love «MSG isn’t bad for you» are misguided — they give a untrue perception of safety to a compound that not everyone should be consuming.
Follow every of the Expert Voices issues and debates — and become part of the discussion — on , and +.
The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science.
In the port city of Yokohama, south of Tokyo, there is a museum devoted entirely to noodle soup. It may be Japan’s favourite foodie day out: one and a half million ramen fans visit the museum every year, and even on the wintry morning that I went the queue wound 50 yards below the highway — young couples, mainly: freezing, hungry and excited.
Inside the Yokohama Ramen Museum and Amusement Park they meet exhibitions on the evolution of soup bowls and instant noodle packets — more fascinating than you’d ponder, but these are not the main event.
That’s deep in the basement, where there’s an entire highway, done up to glance love a raucous s Yokohama harbour-front. Every store houses a diverse noodle restaurant, each a clone of one of the best noodle shops of Japan. It’s a culinary Madame Tussauds.
The Japanese are sentimental about their noodle soup — it’s the working-class food that nourished the nation in the bleak days after World War Two. Ramen chefs are TV celebs, in a country that devotes more broadcast time to cookery than even we do.
I asked the young pilgrims just what they valued above every in ramen. They sniffed the tangy air, Bisto-kid style: ‘The basis of the experience is the broth,’ was the consensus. In the grand Japanese cod-Western Tampopo — the only movie to take noodle soup, sex and death with equal seriousness — a ramen guru announces that the key to Japan’s national dish is that ‘the soup must animate the noodles’.
What does mainly animate Japanese soups and broths is an amino acid called glutamate. In the best ramen shops it’s made naturally from boiling dried kombu seaweed; it can also come from dried shrimp or bonito flakes, or from fermented soy. More cheaply and easily, you get it from a tin, where it is stabilised with ordinary salt and is thus monosodium glutamate.
This final fact is of little interest to the Japanese — love most Asians, they own no fear of MSG.
And there lies one of the world’s grand food scare conundrums. If MSG is bad for you — as Jeffrey Steingarten, the grand American Vogue food author once put it — why doesn’t everyone in China own a headache?
To start to answer this we must go back to Japan a century ago. Professor Kidunae Ikeda comes home from the physics faculty at the Tokyo Imperial University and sits below to eat a broth of vegetables and tofu prepared by his wife.
It is — as usual — yummy. The professor, a mild, bespectacled biochemistry specialist, turns to Mrs Ikeda and asks — as spouses occasionally will — what is the secret of her amazing soup. Mrs Ikeda points to the strips of dried seaweed she keeps in the store cupboard. This is kombu, a heavy kelp. Soak it in boiling water and you get the essence of dashi, the stock base of the tangy broths and consommés the Japanese love.
This is the professor’s ‘Eureka!’ moment. Mrs Ikeda’s kombu is to lead him to a discovery that will make his fortune and change the nature of 20th-century food.
In time, it would bring about the world’s longest-lasting food scare, and as a result, kick-start the age of the rebel consumer. It was an significant piece of seaweed.
Professor Ikeda was one of numerous scientists at the turn of the century working on the biochemical mechanics which inform our perception of the world. By they had drawn a map of the tongue, showing, crudely, the whereabouts of the diverse nerve endings that identify the four accepted primary tastes, sweet, sour, bitter and salty.
But Ikeda thought this matrix missed something.
‘There is,’ he said, ‘a taste which is common to asparagus, tomatoes, cheese and meat but which is not one of the four well-known tastes.’ He decided to call the fifth taste ‘umami’ — a common Japanese expression that is generally translated as ‘savoury’ — or, with more magic, as ‘deliciousness’. By isolating umami, Ikeda — who had picked up some liberal notions while studying in Germany — hoped he might be capable to improve the standard of living of Japan’s rural poor. And so he and his researchers began their quest to isolate deliciousness.
By the work on kombu was finish.
Ikeda made his grand announcement in the august pages of the Journal of the Chemical Society of Tokyo. He had isolated, he wrote, a chemical with the molecular formula C5H9NO4. This and the substance’s other properties were exactly the same as those of glutamic acid, an amino acid produced by the human body and present in numerous foodstuffs. When the protein containing glutamic acid is broken below — by cooking, fermentation or ripening — it becomes glutamate.
‘This study,’ concluded Professor Ikeda in triumph, ‘has discovered two facts: one is that the broth of seaweed contains glutamate and the other that glutamate causes the taste sensation «umami».’
The next step was to stabilise the chemical.
This was easy: mixing it with ordinary salt and water made monosodium glutamate — a white crystal soluble in water and simple to store. By the time he published his paper, the professor had, wisely, already patented MSG. He began to market it as a table condiment called Aji-no-moto (‘essence of taste’) that same year.
It was an instant success, and when Kidunae Ikeda died in he was a wealthy man: he remains, as every Japanese schoolchild knows, one of Japan’s 10 greatest inventors. The food chemicals giant Ajinomoto Corp, now owned by General Foods, pumps out a third of the million tons of monosodium glutamate we eat every year — from India to Indonesia ‘Ajinomoto’ means MSG.
Ikeda’s original paper muses a little about MSG and why it should excite the taste buds so, without arriving at any convincing conclusion.
Much more work has been done since. We now know that glutamate is present in almost every food stuff, and that the protein is so vital to our functioning that our own bodies produce 40 grams of it a day. Probably the most significant discovery in explaining human interest in umami is that human milk contains large amounts of glutamate (at about 10 times the levels present in cow’s milk). Babies own extremely basic taste buds: it’s believed that mother’s milk offers two taste enhancements — sugar (as lactose) and umami (as glutamate) in the hope that one or other will get the little blighters drinking.
Which means mothers’ milk and a packet of cheese’n’onion crisps own rather more in common than you’d think.
When you next grate parmesan cheese onto some dull spaghetti, what you will own done in essence is add a shed-load of glutamate to stimulate your tongue’s umami receptors, thus sending a message to the brain which signals (as one neuro-researcher puts it) ‘Joy and happiness!’ Supper is rescued — and your system has added some protein and fats to a meal that was every carbohydrate.
Ripe cheese is full of glutamate, as are tomatoes. Parmesan, with mg per grams, is the substance with more free glutamate in it than any other natural foodstuff on the planet. Almost every foods own some naturally occurring glutamate in them but the ones with most are obvious: ripe tomatoes, cured meats, dried mushrooms, soy sauce, Bovril and of course Worcester sauce, nam pla (with mg per g) and the other fermented fish sauces of Asia.
Your mate, Marmite, with mg per g, has more glutamate in it than any other manufactured product on the planet — except a jar of Gourmet Powder straight from the Ajinomoto MSG factory.
On the label, Marmite calls it ‘yeast extract’. Nowhere in every their literature does the expression ‘glutamate’ appear. I asked Unilever why they were so bashful about their spread’s key ingredient, and their PR told me that it was because it was ‘naturally occurring the glutamate occurs naturally in the yeast’.
As they put monosodium glutamate into production, Professor Ikeda and his commercial partners found that making stable glutamate from the traditional seaweed and salt was unnecessary. They developed a much simpler and cheaper process using fermented molasses or wheat — eventually manufacturers realised that almost any protein can be broken below to produce it.
The product took off, immediately, and within a few years Ajinomoto (which was now the company’s name) was selling MSG across Asia.
The breakthrough to America came in the aftermath of World War Two. Love pizza and vermouth, MSG was a taste American soldiers brought home with them. They weren’t aware that MSG was what they’d liked in Japan — but the US Army catering staff noticed that their men enjoyed the leftover ration packs of the demobilised Japanese Army much more than they did their own, and began to enquire why.
MSG arrived in America at a key moment. Mass production of processed food was booming. But canning, freezing and pre-cooking own a grave technical problem in common — loss of flavour. And MSG was a cheap and simple additive that made everything taste better.
It went into tinned soups, salad dressings, processed meats, carbohydrate-based snacks, ice cream, bread, canned tuna, chewing gum, baby food and soft drinks. As the industry progressed, it was used in frozen, chilled and dehydrated ready meals. MSG is crucial in no-fat or low-fat food, where natural flavour is lost with the extraction of oils. It’s now found in cosmetics, pharmaceuticals, and dietary supplements.
Ajinomoto Corp started manufacturing in the States in and in allied itself with Kellogg’s.
MSG sells in the States in supermarkets, under the brand Ac’cent. In Britain you will own to visit a Chinese supermarket for a supply of pure Gourmet Powder, but MSG plays a role — often in secret — in products on almost every shelf of the supermarket.
But MSG’s conquest of the planet hit a major bump in April , when, in the New England Journal of Medicine, a Dr Ho Man Kwok wrote a chatty article, not specifically about MSG, whose knock-on effects were to panic the food industry. ‘I own experienced a strange syndrome whenever I own eaten out in a Chinese restaurant, especially one that served northern Chinese food.
The syndrome, which generally begins 15 to 20 minutes after I own eaten the first dish, lasts for about two hours, without hangover effect. The most prominent symptoms are numbness at the back of the neck, gradually radiating to both arms and the back, general weakness and palpitations’
And so was born Chinese restaurant syndrome (CRS) and a medico-academic industry dedicated to the researching and publicising of the dangers of MSG — the foreign migrant contaminating American kitchens.
Shortly after Dr Ho came Dr John Olney at Washington University, who in injected and force-fed newborn mice with huge doses of up to four grams/kg bodyweight of MSG. He reported that they suffered brain lesions and claimed that the MSG found in just one bowl of tinned soup would do the same to the brain of a two-year-old.
Other scientists were testing MSG and finding no evidence of harm — in one study 11 humans ate up to grams of the stuff every day for six weeks without any adverse reactions. At the University of Western Sydney the researchers concluded, tersely: ‘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.’
Science has still not found a convincing explanation for CRS: indeed, some researchers propose it may well be to do with the other things diners own imbibed there — peanuts, shellfish, large amounts of lager.
Others tell that fear of MSG is a form of mass psychosis — you suffer the symptoms you’ve been told to worry about.
The fact is that, since the eighties, mainstream science has got bored of MSG. Some research continues; in , for example, New Scientist got extremely excited over a report that MSG might damage your eyesight, after Japanese scientists announced that they had produced retinal thinning in baby rats fed with MSG. It turned out they were putting 20 grams of MSG in every g of rat food — an amazing quantity, given that, in the UK, we adults consume about four grams of it each a week.
(One project took people who were convinced their asthma was caused by MSG and fed them up to six grams of it a day, without ill-effects). However, at no time has any official body, governmental or academic, ever found it necessary to warn humans against consuming MSG.
But favorite opinion has travelled — spectacularly — in the opposite direction to science. By the early eighties, fuelled by books love Russell Blaylock’s Excitotoxins — The Taste That Kills, MSG’s name was utter mud. MSG today, and you’ll discover it blamed for causing asthma attacks, migraines, hypertension and heart disease, dehydration, chest pains, depression, attention deficit disorder, anaphylactic shock, Alzheimer’s and Parkinson’s diseases and a host of diverse allergies.
Thus since the processed food industry has had its own nasty headache as a result of MSG.
Hundreds of processed products would own to be withdrawn if amino-acid based flavour-enhancers could not be used. They would become, simply, tasteless. By the s a third of every Americans believed it was actively harmful. Crisp-buying teenagers thought MSG made them stupid and spotty. Mothers read that MSG could put holes in their children’s brains.
So the food industry employed its usual tactic in the face of consumer criticism: MSG was buried by giving it new names. The industry came up with a fabulous range of euphemisms for monosodium glutamate — the most cheeky of every is ‘natural flavourings’ (however, the industry did remove MSG from high-end baby foods).
Nowadays the industry’s PR beats a large drum.
‘Natural, Tasty, Safe’ is the slogan. ‘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,’ explains an MSG website.
MSG manufacturers are now pushing it as actively useful for health — a way to eat less salt — and they own pursued the celebrity route too. Heston Blumenthal, of the Fat Duck in Bray, is among the eminent chefs the industry has enlisted for promotion of the umami principle at conferences across the world — although he uses traditional sources love kombu.
It’s not surprising that the MSG-makers are so busy on their product’s image, because MSG-phobia still shows no signs of subsiding.
This despite the fact that every concerned public body that ever investigated it has given it a clean bill of health, including the EU, the United Nations food agencies (which in put MSG on the list of ‘safest food additives’), and the British, Japanese and Australian governments.
In fact, every government across the world that has a food licensing and testing system gives MSG — ‘at normal levels in the diet’ — the thumbs-up. The US Food and Drug istration has three times, in , and , reviewed the evidence, tested the chemical and pronounced it ‘genuinely recognised as safe.
However, there remains a body of respected nutritionists who are certain MSG causes problems — especially in children.
And parents hear. Most doctors who offer guides to parents qualify their warnings about MSG — it may cause problems, it has been anecdotally linked with disorders.
But public figures love the best-selling nutrition guru Patrick Holford are powerful advocates against MSG. He’s certain the science shows that MSG causes migraines and he is convinced of the dangers of the substance to children, particularly in the child-grabber snacks love Monster Munch and Cheesy Wotsits .
‘I’m a practitioner and there’s no doubt that kids with behavioural problems react to MSG,’ he says. ‘I’ve given them the foods, and seen the diverse reactions. Glutamate is a brain stimulant in the way that it is given, because it enhances sensory perception in the sense that things taste much better — and some kids become extremely hyperactive.’
Holford admits that he has not measured this hyperactivity, or tested MSG by itself on children — his statements are based on anecdotal comparison of the effects of plain crisps versus flavoured ones.
But there is some justice in his complaint that in every the acres of research on MSG, ‘most is directed at the possible physiological effects, not the behavioural ones’.
Eric Taylor, professor of kid and adolescent psychiatry at King’s College in London, is among the leading British experts on food additives and children’s behaviour. He was a pioneer of ‘elimination tests’ that examined food additives and their effect on children — establishing, for one, that the colouring tartrazine did contribute to hyperactivity.
Yet he does not ponder MSG is a culprit and he has never tested it.
Why? ‘There are so numerous substances, and there’s not much funding. And, with MSG, there’s no reasonable physiological theorem to justify the research.’ The only investigation he has seen on children’s brains and MSG, conducted in the seventies, suggested that the substance might improve reading ability.
Patrick Holford, love numerous of MSG’s foes, also talks of its possible addictive properties and he cannot explain why ‘natural’ glutamate, tell in cheese or parma ham, should be any less addictive, or harmful, than glutamate that’s been industrially produced and stabilised with salt.
The anti-additive movement (check out the excellent and informative ) admits that ‘natural’ and ‘industrially produced’ glutamate are chemically the same, and treated by the body similarly.
So why doesn’t anyone ever complain of a headache or hyperactivity after a four cheese and tomato pizza (where there’s easily as much glutamate as in an MSG-enhanced chicken chow mein)?
Their answer is that the industrial fermentation process introduces contaminants. This is possible, of course, but it ignores the fact that whole swaths of the planet — including East Asia, where I live — do not own any problem with MSG. Here in Thailand, the phong chu rot sits on the table with the fish sauce and the chilli powder where you would own the salt and pepper.
MSG has had one unarguable effect on us — and it is a benign one. It has made consumers glance at the little print. In turn this kick-started the organic food movement and other, more militant consumer power groups.
was a excellent year for rebels, and the dawn of MSG-phobia coincides with the beginning of a grand shift in middle-class consumers’ thinking — a withdrawal of our faith in the vast corporations that fed and medicated us. After we began to question them and their motives. Friends of the Ground and Greenpeace came next.
It is now 37 years since Dr Ho Man Kwok named Chinese restaurant syndrome, and it’s plain that the case against MSG remains unproven. So either you conclude, as some will, that government, science and the mega-corporates of the food industry really are every in league with each other to poison us for profit.
Or, love me, you make a diverse decision.
Now, I own little faith in the food industry and I’m as suspicious of food additives as the next person — I spend numerous hours fighting the grim battle to hold them from my children’s mouths. But until new evidence emerges I am going to give MSG a conditional discharge. But would I own it in the kitchen? Well, I did. I bought a little bag of Ajinomoto from the corner store on our Bangkok highway and tried it, a gram (the tip of a teaspoon) at a time.
By itself it tasted of almost nothing.
So I beat up and fried two eggs, and tried one with MSG, one without. The MSG one had more egg flavour, and didn’t need any salting. I tried the crystals on my son’s leftover pieces of chicken breast (definitely more chickeny). I tried it in a peanut butter sandwich (nothing). On Weetabix with milk (interesting, sort of malty) and on Weetabix with milk and sugar (thought I was going to be sick).
My friend Nic came circular. He told me about a Japanese restaurant he’d been to that gave him headaches and a ‘weird tingling in the cheeks’ — until he told them to stop with the MSG. Then he was fine, he said. I nodded and I served him two tomato and chive salads; both were made using the extremely same ingredients but I told him one plate of tomatoes was ‘organic’, the other ‘factory-farmed’.
The organic tomatoes were far better, we agreed. These, of course, were the tomatoes doused with mono sodium glutamate.
Then we ate mascarpone, parma ham and tomato pizza. Nic felt fine. So did I. I had ingested, I reckoned, a excellent six grams of MSG over the day, and probably the same again in free glutamate from the food — the equivalent of eating two g jars of Marmite.
I’ve thrown the Ajinomoto out now. It works, but it was embarrassing — a bit love having a packet of Bisto in the cupboard.
There is no need to own MSG in the kitchen. If I desire additional glutamate in my food I’ll use parmesan, or tomato purée, or soy sauce. Or love Mrs Ikeda, boil up some kelp.
So you ponder you don’t eat MSG? Ponder again
Some of the names MSG goes under
autolyzed yeast extract
E (E are every glutamates)
The following may also contain MSG natural flavours or seasonings
natural beef or chicken flavouring
hydrolyzed milk or plant protein
Free glutamate content of foods (mg per g) roquefort cheese
unused tomato juice
human milk 22
For more on the MSG debate visit: , , or
This article is about the chemical compound.
For its use in food, see glutamate flavoring. See also glutamic acid, Ajinomoto, and MSG (disambiguation).
3D model (JSmol)
|E number||E (flavour enhancer)|
|Molar mass||g/mol (anhydrous), g/mol (monohydrate)|
|Appearance||White crystalline powder|
|Melting point||°C (°F; K)|
Solubility in water
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|mg/kg (oral, rat)|
Except where otherwise noted, data are given for materials in their standard state (at 25°C [77°F], kPa).
Monosodium glutamate (MSG), also known as sodium glutamate, is the sodiumsalt of glutamic acid, one of the most abundant naturally occurring non-essentialamino acids. Glutamic acid is found naturally in tomatoes, grapes, cheese, mushrooms and other foods. MSG is used in the food industry as a flavor enhancer with an umami taste that intensifies the meaty, savory flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups.
MSG was first prepared in by Japanese biochemistKikunae Ikeda, who was trying to isolate and duplicate the savory taste of kombu, an edible seaweed used as a base for numerous Japanese soups.
MSG balances, blends, and rounds the perception of other tastes. MSG is commonly found in stock (bouillon) cubes, soups, ramen, gravy, stews, condiments, savoury snacks, etc. After , it became known for its use in Chinese restaurants.
The U.S. Food and Drug istration has given MSG its generally recognized as safe (GRAS) designation. A favorite belief is that MSG can cause headaches and other feelings of discomfort, known as «Chinese restaurant syndrome», but blinded studies show no such effects when MSG is combined with food in normal concentrations, and are inconclusive when MSG is added to broth in large concentrations. The European Union classifies it as a food additive permitted in certain foods and subject to quantitative limits.
MSG has the HS code and the E number E
MSG is safe to consume. A favorite belief is that MSG can cause headaches and other feelings of discomfort but blinded tests own found no excellent evidence to support this. MSG has been used for more than years to season food, with a number of studies conducted on its safety.
Consumption and manufacture of high-salt and high-glutamate foods, which contain both sodium and glutamate, stretch back far longer, with evidence of cheese manufacture as early as 5, BCE. International and national bodies governing food additives currently consider MSG safe for human consumption as a flavor enhancer. Under normal conditions, humans can metabolize relatively large quantities of glutamate, which is naturally produced in the gut in the course of protein hydrolysis. The median lethal dose (LD50) is between 15 and 18 g/kg body weight in rats and mice, respectively, five times the LD50 of sodium chloride (3 g/kg in rats).
The use of MSG as a food additive and the natural levels of glutamic acid in foods are not toxicological concerns in humans.
A report from the Federation of American Societies for Experimental Biology (FASEB) for the United States Food and Drug istration (FDA) concluded that MSG is safe when «eaten at customary levels» and, although a subgroup of otherwise-healthy individuals develop an MSG symptom complicated when exposed to 3 g of MSG in the absence of food, MSG as a cause has not been established because the symptom reports are anecdotal.
According to the report, no data supports the role of glutamate in chronic disease.
A controlled, blinded, multiple-location clinical trial failed to protest a relationship between the MSG symptom complicated and actual MSG consumption. No statistical association has been demonstrated, and the few responses were inconsistent. No symptoms were observed when MSG was istered with food.
Adequately controlling for experimental bias includes a blinded, placebo-controlledexperimental design (DBPC) and istration by capsule, because of the unique aftertaste of glutamates. In a study by Tarasoff and Kelly (), 71 fasting participants were given 5 g of MSG and then a standard breakfast.
One reaction (to the placebo, in a self-identified MSG-sensitive individual) occurred. A study by Geha et al. () tested the reaction of subjects with a reported sensitivity to MSG. Multiple DBPC trials were performed, with subjects exhibiting at least two symptoms continuing.
Two people out of the responded to every four challenges. Because of the low prevalence, the researchers concluded that a response to MSG was not reproducible.
Studies exploring MSG’s role in obesity own yielded mixed results.
Although several studies own investigated anecdotal links between MSG and asthma, current evidence does not support a causal association. Since glutamates are significant neurotransmitters in the human brain, playing a key role in learning and memory, ongoing neurological studies indicate a need for further research.
Food Standards Australia New Zealand (FSANZ) MSG technical report concludes, «There is no convincing evidence that MSG is a significant factor in causing systemic reactions resulting in severe illness or mortality.
The studies conducted to date on Chinese restaurant syndrome (CRS) own largely failed to protest a causal association with MSG. Symptoms resembling those of CRS may be provoked in a clinical setting in little numbers of individuals by the istration of large doses of MSG without food. However, such effects are neither persistent nor serious and are likely to be attenuated when MSG is consumed with food. In terms of more serious adverse effects such as the triggering of bronchospasm in asthmatic individuals, the evidence does not indicate that MSG is a significant trigger factor.»
However, the FSANZ MSG report says that although no data is available on average MSG consumption in Australia and New Zealand, «data from the United Kingdom indicates an average intake of mg/day, with extreme users (th percentile consumers) consuming mg/day» (Rhodes et al.
). In a highly seasoned restaurant meal, intakes as high as mg or more may be possible (Yang et al. ). When extremely large doses of MSG (>5 g MSG in a bolus dose) are ingested, plasma glutamate concentration will significantly increase. However, the concentration typically returns to normal within two hours. In general, foods providing metabolizable carbohydrate significantly attenuate peak plasma glutamate levels at doses up to mg/kg body weight. Two earlier studies the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and the Federation of American Societies for Experimental Biology (FASEB) concluded, «there may be a little number of unstable asthmatics who reply to doses of – g of MSG in the absence of food».
The FASEB evaluation concluded, «sufficient evidence exists to indicate some individuals may experience manifestations of CRS when exposed to a ≥3 g bolus dose of MSG in the absence of food».
MSG Allergy Versus Sensitivity: Why Does It Matter?
Distinguishing between an allergy and a sensitivity is significant because the treatment for each is diverse. The science behind allergies is fairly well-understood. There a number of treatments for symptoms, including medications and injections.
The science behind food sensitivity to MSG isn’t as established.
Glutamate, the main ingredient in MSG, is a neurotransmitter — a chemical that carries messages in the nervous system. Scientists own been searching for a link between glutamate in the nervous system and the symptoms of MSG sensitivity.
But a connection has not yet been made. So for now, Nish says, avoiding MSG if it bothers you is the best thing to do.
While MSG is best known for its use in restaurants, it can also be found in frozen meals, packaged snack foods, canned foods and soups, and even seasoning mixes. Check the ingredients lists on food labels. As a general law of thumb, if you eat something that gives you a reaction you’ve had before you should eliminate that food from your diet.
The compound is generally available as the monohydrate, a white, odorless, crystalline powder.
The solid contains separate sodium cations Na+
and glutamate anions in zwitterionic form, −OOC-CH(NH+
2)2-COO−. In solution it dissociates into glutamate and sodium ions.
MSG is freely soluble in water, but it is not hygroscopic and is insoluble in common organic solvents (such as ether). It is generally stable under food-processing conditions. MSG does not break below during cooking and, love other amino acids, will exhibit a Maillard reaction (browning) in the presence of sugars at extremely high temperatures.
MSG has been produced by three methods: hydrolysis of vegetable proteins with hydrochloric acid to disrupt peptide bonds (–); direct chemical synthesis with acrylonitrile (–), and bacterial fermentation (the current method).Wheat gluten was originally used for hydrolysis because it contains more than 30 g of glutamate and glutamine in g of protein.
As demand for MSG increased, chemical synthesis and fermentation were studied. The polyacrylic fiber industry began in Japan during the mids, and acrylonitrile was adopted as a base material to synthesize MSG.
Currently (), most global MSG is produced by bacterial fermentation in a process similar to making vinegar or yogurt. Sodium is added later, for neutralization. During fermentation, Corynebacterium species, cultured with ammonia and carbohydrates from sugar beets, sugarcane, tapioca or molasses, excrete amino acids into a culture broth from which L-glutamate is isolated.
The Kyowa Hakko Kogyo Company developed industrial fermentation to produce L-glutamate.
The conversion yield and production rate (from sugars to glutamate) continues to improve in the industrial production of MSG, keeping up with demand. The product, after filtration, concentration, acidification, and crystallization, is glutamate, sodium, and water.
Pure MSG is reported to not own a highly pleasant taste until it is combined with a savory aroma. The basic sensory function of MSG is attributed to its ability to enhance savory taste-active compounds when added in the proper concentration. The optimum concentration varies by food; in clear soup, the pleasure score rapidly falls with the addition of more than one gram of MSG per mL.
The sodium content (in mass percent) of MSG, 12%, is about one-third of that in sodium chloride (39%), due to the greater mass of the glutamate counterion. Although other salts of glutamate own been used in low-salt soups, they are less palatable than MSG. «MSG might even promote healthy eating, (food scientist Steve Witherly) hypothesizes, by not only making kale more yummy but also letting you get away with using less salt.»
MSG is commonly used and found in stock cubes (Bouillon cube), soups, ramen, gravy, stews, condiments, savoury snacks etc.
The ribonucleotide food additives disodium inosinate (E) and disodium guanylate (E), as well as conventional salt are generally used with monosodium glutamate-containing ingredients as they seem to own a synergistic effect. «Super salt» is a mixture of 9 parts salt, to one part MSG and parts disodium inosinate and disodium guanylate.