Monosodium Glutamate (MSG)
<p><b >Monosodium glutamate</b>, also known as <b >sodium glutamate</b> or <b >MSG</b>, is the <a href="http://en.wikipedia.org/wiki/Sodium_salt" title="Sodium salt" class="mw-redirect" >sodium salt</a> of <a href="http://en.wikipedia.org/wiki/Glutamic_acid" title="Glutamic acid" >glutamic acid</a>, one of the most abundant naturally occurring<a href="http://en.wikipedia.org/wiki/Essential_amino_acid" title="Essential amino acid" >non-essential</a> <a href="http://en.wikipedia.org/wiki/Amino_acid" title="Amino acid" >amino acids</a>.<sup id="cite_ref-natural_occurrence_0-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-natural_occurrence-0" >[1]</a></sup> </p>
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It was classified by the U.S. <a href="http://en.wikipedia.org/wiki/Food_and_Drug_Administration" title="Food and Drug Administration" >Food and Drug Administration</a> as <a href="http://en.wikipedia.org/wiki/Generally_recognized_as_safe" title="Generally recognized as safe" >generally recognized as safe</a> (GRAS) and by the European Union as a <a href="http://en.wikipedia.org/wiki/Food_additive" title="Food additive" >food additive</a>. MSG has the <a href="http://en.wikipedia.org/wiki/Harmonized_System_Code" title="Harmonized System Code" class="mw-redirect" >HS code</a> 29224220 and the <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E number</a>E621.<sup id="cite_ref-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-1" >[2]</a></sup> </p>
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The glutamate of MSG confers the same <a href="http://en.wikipedia.org/wiki/Umami" title="Umami" >umami</a> taste of glutamate from other foods, being chemically identical.<sup id="cite_ref-Ikeda_2-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-Ikeda-2" >[3]</a></sup> Industrial food manufacturers market and use MSG as a flavor enhancer because it balances, blends and rounds the total perception of other tastes.<sup id="cite_ref-Loliger_3-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-Loliger-3" >[4]</a></sup><sup id="cite_ref-Yamaguchi91_4-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-Yamaguchi91-4" >[5]</a></sup> Trade names of monosodium glutamate include Ac'cent, Aji-No-Moto, and Vetsin.</p>
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Since <a href="http://en.wikipedia.org/wiki/Glutamates" title="Glutamates" class="mw-redirect" >glutamates</a> are important <a href="http://en.wikipedia.org/wiki/Neurotransmitters" title="Neurotransmitters" class="mw-redirect" >neurotransmitters</a> in the human brain, playing a key element in learning and memory, there is ongoing study by <a href="http://en.wikipedia.org/wiki/Neurologists" title="Neurologists" class="mw-redirect" >neurologists</a> about possible side-effects of MSG in food but no conclusive studies drawing any connections.<sup id="cite_ref-twsNovK8d_27-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Monosodium_glutamate#cite_note-twsNovK8d-27" >[28]</a></sup></p>
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Monosodium glutamate (MSG) is one of several forms of glutamic acid found in foods, in large part because glutamic acid, being an amino acid, is pervasive in nature. </p>
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Glutamic acid and its salts can also be present in a wide variety of other additives, including <a href="http://en.wikipedia.org/wiki/Hydrolyzed_vegetable_protein" title="Hydrolyzed vegetable protein" class="mw-redirect" >hydrolyzed vegetable protein</a>, <a href="http://en.wikipedia.org/wiki/Autolyzed_yeast" title="Autolyzed yeast" class="mw-redirect" >autolyzed yeast</a>, <a href="http://en.wikipedia.org/wiki/Hydrolyzed_yeast" title="Hydrolyzed yeast" class="mw-redirect" >hydrolyzed yeast</a>, <a href="http://en.wikipedia.org/wiki/Yeast_extract" title="Yeast extract" >yeast extract</a>, <a href="http://en.wikipedia.org/wiki/Soy" title="Soy" class="mw-redirect" >soy</a> extracts, and protein isolate, which must be labeled with these common and usual names. Since 1998, MSG cannot be included in the term "spices and flavorings". </p>
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The food additives <a href="http://en.wikipedia.org/wiki/Disodium_inosinate" title="Disodium inosinate" >disodium inosinate</a> and <a href="http://en.wikipedia.org/wiki/Disodium_guanylate" title="Disodium guanylate" >disodium guanylate</a>,
which are <a href="http://en.wikipedia.org/wiki/Ribonucleotides" title="Ribonucleotides" class="mw-redirect" >ribonucleotides</a>, are usually used in synergy with monosodium glutamate-containing ingredients. </p>
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However, the term "natural flavor" is now used by the food industry when using glutamic acid (which is similar to MSG, lacking only the sodium ions)<sup class="Template-Fact" >[<i><a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed" >citation needed</a></i>]</sup>. </p>
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Due to lack of FDA regulation, it is impossible to determine what percentage of "natural flavor" is actually glutamic acid<sup class="Template-Fact" >[<i><a href="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed" >citation needed</a></i>]</sup>.</p>
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The FDA considers labels such as "No MSG" or "No Added MSG" to be misleading if the food contains ingredients that are sources of free glutamate, such as hydrolyzed protein. </p>
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In 1993, the FDA proposed adding the phrase "(contains glutamate)" to the common or usual names of certain protein hydrolysates that contain substantial amounts of glutamate.
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