One of the most frequent questions I get when speaking about my book is the MSG question. My talk is about L-glutamate, the taste of umami and veal stock (it makes a little more sense if you've read the book) and, before I get to the punchline, I'm inevitably interrupted by someone insisting that MSG is toxic.* I will now refer all interested parties to this Times article:
Even now, after "Chinese restaurant syndrome" has been thoroughly debunked (virtually all studies since then confirm that monosodium glutamate in normal concentrations has no effect on the overwhelming majority of people), the ingredient has a stigma that will not go away.
But then, neither will MSG.
Cooks around the world have remained dedicated to MSG, even though they may not know it by that name. As hydrolyzed soy protein or autolyzed yeast, it adds flavor to the canned chicken broth and to the packs of onion soup mix used by American home cooks, and to the cheese Goldfish crackers and the low-fat yogurts in many lunchboxes.
It is the taste of Marmite in the United Kingdom, of Golden Mountain sauce in Thailand, of Goya SazÃ³n on the Latin islands of the Caribbean, of Salsa Lizano in Costa Rica and of Kewpie mayonnaise in Japan.
"It's all the same thing: glutamate," said Dr. Nuripa Chaudhari of the University of Miami, who was part of the first research team to identify human glutamate receptors.
And, as I argue in my book, glutamate is also the taste of veal stock and classic French culinary technique. The pioneering achievement of Auguste Escoffier, the chef who helped invent modern French cuisine, was getting as much denatured glutamate on the plate as possible.
What I find most fascinating about this fifth taste is that it was neglected by science for so long. Even after chefs constructed entire cuisines around the potency of glumatate, and food companies were putting MSG in everything from bouillon cubes to Marmite, the science of the tongue remained tethered to this Aristotelian idea that there were four, and only four, taste sensations (sweet, sour, salty and bitter). But how do those four taste sensations explain the allure of parmesan cheese or the rich taste of a demi-glace or the mouth-filling allure of a porcini mushroom pasta? The answer is simple: they don't.
*My guess is that people latched onto MSG as the cause of migraines - the so-called "Chinese food syndrome" - because glutamate is also a neurotransmitter. Thus, it makes sense that monosodium glutamate might have some psychoactive properties.
It is more MSG is used to make fat rats & mice for animal testing because they eat more when fed MSG. So the only reason to add MSG to food is to get you to eat more.
At least that is one of the reasons I've seen.
Funny, I just had a conversation over lunch about this issue.
I like knowing there's a reason to go to all the trouble of browning/deglazing/etc... time = flavor!
Glutamate can be neurotoxic, but I don't think it's a concern unless you're injecting it.
When taken orally, glutamate is largely metabolized by the GI tract.
The French have long had a term that's roughly equivalent to umami. Originated by Brillat-Savarin in "The Physiology of Taste", osmazome can be roughly defined as the sense that "meat has been here" that one gets from good broth, sauces, and soups.
Here is Brillat-Savarin on osmazome:
The greatest service chemistry has rendered to alimentary science, is the discovery of osmazome, or rather the determination of what it was.
Osmazome is the purely sapid portion of flesh soluble in cold water, and separated from the extractive portion which is only soluble in boiling water.
Osmazome is the most meritorious ingredient of all good soups. This portion of the animal forms the red portion of flesh, and the solid parts of roasts. It gives game and venison its peculiar flavor.
Osmazome is most abundant in grown animals which have red or black hair; it is scarcely found at all in the lamb, sucking pig, chicken, and the white meat of the largest fowls. For this reason true connoisseurs always prefer the second joint; instinct with them was the precursor of science.
Thus a knowledge of the existence of osmazome, caused so many cooks to be dismissed, who insisted on always throwing away the first bouillon made from meat. This made the reputation of the soupe des primes, and induced the canon Chevrier to invent his locked kettles. The Abbe Chevrier was the person who never would eat until Friday, lobsters that had not been cooked on the previous Sunday, and every intervening day placed on the fire with the addition of fresh butter.
To make use of this subject, though yet unknown, was introduced the maxim, that to make good bouillon the kettle should only smile.
Osmazome, discovered after having been so long the delight of our fathers, may be compared to alcohol, which made whole generations drunk before it was simply exhibited by distillation.
I get a splitting headache from glutamate. I discovered it during a period when I mainly ate instant noodles. I'm not sure wether that means it's toxic or if I'm allergic, but the effect is very strong.
This is such a fascinating topic. I was amazed when I read the book, and still find it "intoxicating". The idea that somebody would work so hard to figure out a taste. I've been told by many people that I am a very good cook, and I always chuckle at this because most of the time, I can't smell anything. I cook by taste alone - the combination of tastes that hit my tongue. For virtually 95% of the time - sometimes for years at a time, I have not been able to smell anything, but I've always been able to taste. It's fascinating to me that I can distinguish so many flavors just by their taste, without the benefit of smelling them too. This of course allows me to use lots of things that most people would not use - simply because I'm not responding to the smell - just the combination of flavors.
If we think carefully, there are even more flavours.
What, for instance, is the taste of metal? It's certainly not umami or any of the others - yet is has a distinct "flavour".
What, for instance, is the taste of metal? It's certainly not umami or any of the others -
Wouldn't the acidic taste of metal be classified as sour?
Don't forget though that "flavors" are usually a result of the senses of taste and smell working together. How do you think that applies to the glutamate question?
I am highly sensitive to MSG. It is the primary trigger for my Meniere's (a condition of the inner ear). If I eat anything that has MSG in it in higher concentrations, Chinese food, soups, frozen dinners, or eat many foods with a lower concentration over a short period of time, I have a Meniere's attack. This consists of several days of vertigo, nausea, ringing in my ears and numbness in my face. I don't understand the connection, but I have found references. See the Mayo Clinic Article. I am forced to carefully read labels, ask a lot of questions at restaurants and cook most of my own foods (a good thing really, but getting to this point of knowledge was an interesting journey).
Like Jill, I also have a high sensitivity to MSG in all its forms. My guess is that the number of us out there is HUGE, but we have few ways to find each other and do something about our own health.
To avoid pain, I've had to learn how msg is hidden in so many forms and under so many names (...some as benign as 'citric acid'). It's taken a lot of time and careful food diaries to pinpoint what has affected me; my sister and daughter also have similar sensitivities.
It's not a myth.