So my mother’s a drama queen? shrug
What you’ve really gotta worry about, though, is the monocesium glutamate.
It explodes with flavor!
(Bolding mine)
I would consider death to be an “ill effect.”
A good friend of mine from high school was severely allergic to MSG and died from anaphylactic shock after inadvertently eating it.
I know you said “sensitivities” rather than “allergies,” but attitudes such as yours are reprehensible. I don’t dispute that a lot of people’s reactions to MSG are indeed imaginary, but some people do have legitimate and life threatening allergies to the stuff. You can’t assume that that somebody who says “no MSG” is a drama queen. Even if they do have a sensitivity rather than an allergy, it may well be real.
And now I’ll offer something in the “I perhaps shouldn’t reveal this” category–wanna know how my friend died? She was EATING IN A CHINESE RESTAURANT!!! :smack: :smack: :smack: Her MSG allergies were well-established at that point. She had had several episodes of severe anaphylaxis previously and traveled armed with epinepherine. The Chinese restaurant assured her there was no MSG in the food. I always assumed that the people at the restaurant were being sincere, but some bottled ingredient was mislabeled or something. Whether they actually knew or didn’t know that they were giving her MSG is irrelevant, though, because it should be entirely obvious to anyone with a quarter of a brain that if you’re genuinely allergic to MSG, you should stay away from Chinese restaurants. It was one of the stupidest fucking deaths ever.
I wouldn’t entirely rule out very rare sensitivities to it. Phenylalanine is an essential amino acid, but phenylketonuria is a real condition. I still think 99.99% of people that claim they are sensitive are entirely psychosomatic. People assume chemicals are bad and with a name like monosodium glutamate it couldn’t possibly be natural and certainly your own body doesn’t make it.
You know, that’s really not your call to make. If you can’t comply with the limits some diners have on their diets for health reasons then it should be easy enough to simply tell them it’s not something you can provide. To lie to them and let them ingest something because you think it’s okay is, as Green Bean states, reprehensible. You think just because they walked out of your restaurant without keeling over that the possibility of any ill effects was suddenly negligible? Were you so cavalier about peanut oils too? I’d gladly tip my waiters more if I’d known they’d been to med school, only they haven’t.
Aren’t they all? 
Isn’t there some sort of allergy test that can say for sure whether your body reacts negatively toward MSG? We had my son tested for allergies, and they made several pin-like scratches in his back exposing him to many different allergens. Raw egg, peanut, and some kind of grass or pollen tested positive. Especially the peanut. It swelled up to a gigantic, inflamed hive and he started crying his eyes out. The doctor had to smother it with hydrocortisone or some such cream. So, now peanut is a HELL NO item for him. We have to be very careful.
Just wondered if allergists test for that?
I wasn’t making the call. I didn’t work the line at that restaurant, I just did prep and washed dishes. I wasn’t allowed on the woks. I chopped onions and rolled eggrolls, I didn’t cook orders. I wasn’t describing anything I personally did, just reporting what I observed.
Weeeeeeellllll…yeah… 
Interestingly, my family did allergy testing when I was 12 or 13. The skin tests actually did test for certain foods (apparently I’m allergic to cinnamon), but I don’t recall if MSG was one of them.
Yes, they differ by the replacement of one proton by a sodium counter ion - if you dissolve glutamic acid in slighly salty water you get the same thing as by dissolving MSG in slightly sour water, a mixture of protons and sodium ions as counter ions to compensate for the negative charge of dissolved glutamate.
In the context of soy sauce, it does not make any practical difference.
Not a very good analogy. There really *isn’t *a word in English that equates to umami. It’s more like complaining about using the word tortilla. If they say “tortilla” fifty times in the add, it’s silly, but it’s silly because of the repitition, not because of the word.
You are simplifying things just a bit by merely relying on the chemical structure. As an example there are 2 MSG molecules that have the same chemical structure, but are stereoisomers. One enhances flavor the other does not. I was speaking in terms of physiology and in the context of soy sauce it certainly makes a practical difference if you are tasting it.
Kikkoman is serviceable, but there are much, much better brands out there. I find Chinese and Korean soy sauces to be much tastier, especially Kimlan. (Lee Kum Kee used to be awesome, but the last bottle I bought tasted exactly like Kikkoman.)
Just avoid La Choy, whatever you do. That stuff is nasty.
As a biochemist, I would not call stereoisomers the same molecule. But the glutamate you get by digesting (fermenting) soy protein is the L-isomer, independently of whether you talk of the acid or of the sodium salt. And if you start from a racemic mixture of L- and D- glutamic acid, you end up with the same racemic mixture of sodium glutamate, if you disolve the powder in water, adjust the pH with sodium bicarbonate and dry the water off again.
For what is worth, my thai GF is allergic to monosodium glutamate, not drastically so, but if the food contains too much of the stuff she blushes, feels hot and unwell for some time.
There is still no good evidence that MSG causes significant health or life-threatening problems, per a pretty good recent review of the data from Scripps Institute.
I like kikkoman! Show me shoyu!
(hanging cat)
To clarify my post above, I should say that there’s still no good evidence that MSG causes any allergic reactions (that is, IgE-mediated type anaphylaxis, itch, respiratory distress). It certainly may be poorly tolerated, and cause headaches and other symptoms in some folks, but these are not allergic reactions, nor have they been found thus far to be primarily health or life-threatening.
http://allergycases.org/2008/03/intolerance-to-monosodium-glutamate-msg.html
It’s actually impossible to be allergic to MSG. Food alergies are immunological responses to proteins. MSG has no proteins and causes no immunological response. What it does do is stimulate the nervous system. It’s essentially a drug reaction, and in rare cases may cases may overstimulate the nervous system, but pedantically speaking, that would not be an allergic reaction, but a sort of adverse drug reaction.
Are you sure that’s a reaction to the food and not the company?
Basically true. The smallest known allergen is made up of 26 amino acids and is found in bee venom. Predicting allergenic proteins using wavelet transform | Bioinformatics | Oxford Academic