glutamate (MSG) is a flavor enhancer that is commonly found in commercially
prepared frozen dinners, snacks, spice mixes, soups, casseroles, etc. MSG
is also sold to as a general purpose seasoning.
MSG was originally
isolated in 1908 as the component, specifically glutamic acid, in kombu seaweed
that was responsible for the flavor enhancing properties of dashi, the Japanese
broth made with kombu that forms the basis of Japanese cuisine. MSG is now
synthetically produced from a fermentation process of starch and molasses.
The end product is a pure, white, crystalline form of MSG, much more
concentrated than what is naturally occurring in kombu.
In its bound form,
when it is linked with other amino acids to form proteins, glutamic acid does
not provide any special flavor enhancing benefits. It is only in its free
form, unbound to amino acids, that its flavor enhancing properties and potential
risks arise. Free glutamic acid occurs naturally at low levels in foods
such as soy sauce, kombu seaweed, mushrooms, tomatoes, and Parmesan
cheese. Cooks have traditionally used these foods as ingredients in
recipes to help enhance flavors without any serious side effects. In
contrast, pure, concentrated forms of free glutamic acid as present in synthetic
MSG have been shown to cause serious reactions in sensitive individuals.
Given that MSG is
derived, in part, from molasses, it is tame', and therefore forbidden to
consume. Some might be concerned that the loose term "natural
flavors," often present on food labels might hide the presence of MSG;
however, by law foods purchased from grocery stores must be labeled as
containing MSG if they contain concentrated, isolated MSG.