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76-401: Monosodium glutamate ( MSG ), also known as sodium glutamate , is a sodium salt of glutamic acid . MSG is found naturally in some foods including tomatoes and cheese in this glutamic acid form. MSG is used in cooking as a flavor enhancer with a savory taste that intensifies the umami flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups. MSG

152-421: 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 carbohydrates significantly attenuate peak plasma glutamate levels at doses up to 150mg/kg body weight. Two earlier studies – the 1987 Joint FAO / WHO Expert Committee on Food Additives (JECFA) and

228-471: A flame test , sodium and its compounds glow yellow because the excited 3s electrons of sodium emit a photon when they fall from 3p to 3s; the wavelength of this photon corresponds to the D line at about 589.3 nm. Spin-orbit interactions involving the electron in the 3p orbital split the D line into two, at 589.0 and 589.6 nm; hyperfine structures involving both orbitals cause many more lines. Twenty isotopes of sodium are known, but only Na

304-615: A patent to produce MSG; the Suzuki brothers began commercial production of MSG in 1909 using the term Ajinomoto ("essence of taste"). MSG is one of several forms of glutamic acid found in foods, in large part because glutamic acid (an amino acid) is pervasive in nature. Glutamic acid and its salts may be present in a variety of other additives, including hydrolyzed vegetable protein , autolyzed yeast , hydrolyzed yeast , yeast extract , soy extracts, and protein isolate, which must be specifically labeled. Since 1998, MSG cannot be included in

380-423: A phase-transfer catalyst . Sodium content of samples is determined by atomic absorption spectrophotometry or by potentiometry using ion-selective electrodes. Like the other alkali metals, sodium dissolves in ammonia and some amines to give deeply colored solutions; evaporation of these solutions leaves a shiny film of metallic sodium. The solutions contain the coordination complex [Na(NH 3 ) 6 ] , with

456-503: A raising agent , and sodablasting . Along with potassium, many important medicines have sodium added to improve their bioavailability ; though potassium is the better ion in most cases, sodium is chosen for its lower price and atomic weight. Sodium hydride is used as a base for various reactions (such as the aldol reaction ) in organic chemistry. Metallic sodium is used mainly for the production of sodium borohydride , sodium azide , indigo , and triphenylphosphine . A once-common use

532-426: A campaign called "Redefine CRS" to combat what it said was the myth that MSG is harmful to people's health, saying it intended to highlight the xenophobic prejudice against East Asian cuisine and the scientific evidence. Sodium Sodium is a chemical element ; it has symbol   Na (from Neo-Latin natrium ) and atomic number  11. It is a soft, silvery-white, highly reactive metal . Sodium

608-427: A causal association. 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) have largely failed to demonstrate a causal association with MSG. Symptoms resembling those of CRS may be provoked in

684-421: A clinical setting in small numbers of individuals by the administration 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,

760-533: A compound of sodium with the Latin name of sodanum was used as a headache remedy. The name sodium is thought to originate from the Arabic suda , meaning headache, as the headache-alleviating properties of sodium carbonate or soda were well known in early times. Although sodium, sometimes called soda , had long been recognized in compounds, the metal itself was not isolated until 1807 by Sir Humphry Davy through

836-524: A corner of our 60 m room farthest away from the apparatus, we exploded 3 mg of sodium chlorate with milk sugar while observing the nonluminous flame before the slit. After a while, it glowed a bright yellow and showed a strong sodium line that disappeared only after 10 minutes. From the weight of the sodium salt and the volume of air in the room, we easily calculate that one part by weight of air could not contain more than 1/20 millionth weight of sodium. The Earth's crust contains 2.27% sodium, making it

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912-534: 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 (LD 50 ) is between 15 and 18 g/kg body weight in rats and mice, respectively, five times the LD 50 of table salt (3 g/kg in rats). The use of MSG as a food additive and the natural levels of glutamic acid in foods are not of toxic concern in humans. Specifically MSG in

988-567: A high affinity for the sodium ion; derivatives of the alkalide Na are obtainable by the addition of cryptands to solutions of sodium in ammonia via disproportionation . Many organosodium compounds have been prepared. Because of the high polarity of the C-Na bonds, they behave like sources of carbanions (salts with organic anions ). Some well-known derivatives include sodium cyclopentadienide (NaC 5 H 5 ) and trityl sodium ((C 6 H 5 ) 3 CNa). Sodium naphthalene , Na [C 10 H 8 •] ,

1064-415: A high neutron flux in the reactor. The high boiling point of sodium allows the reactor to operate at ambient (normal) pressure, but drawbacks include its opacity, which hinders visual maintenance, and its strongly reducing properties. Sodium will explode in contact with water, although it will only burn gently in air. Radioactive sodium-24 may be produced by neutron bombardment during operation, posing

1140-466: A nutrient for animals including humans. Sodium is an essential element for all animals and some plants. Sodium ions are the major cation in the extracellular fluid (ECF) and as such are the major contributor to the ECF osmotic pressure . Animal cells actively pump sodium ions out of the cells by means of the sodium–potassium pump , an enzyme complex embedded in the cell membrane , in order to maintain

1216-516: 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. Kyowa Hakko Kogyo (currently Kyowa Kirin ) developed industrial fermentation to produce L-glutamate. The conversion yield and production rate (from sugars to glutamate) continues to improve in

1292-888: A result, sodium usually forms ionic compounds involving the Na cation. Metallic sodium is generally less reactive than potassium and more reactive than lithium . Sodium metal is highly reducing, with the standard reduction potential for the Na /Na couple being −2.71 volts, though potassium and lithium have even more negative potentials. Sodium compounds are of immense commercial importance, being particularly central to industries producing glass , paper , soap , and textiles . The most important sodium compounds are table salt (Na Cl ), soda ash (Na 2 CO 3 ), baking soda (Na HCO 3 ), caustic soda (NaOH), sodium nitrate (Na NO 3 ), di- and tri- sodium phosphates , sodium thiosulfate (Na 2 S 2 O 3 ·5H 2 O), and borax (Na 2 B 4 O 7 ·10H 2 O). In compounds, sodium

1368-495: A result, the committee has established Adequate Intake (AI) levels instead, as follows. The sodium AI for infants of 0–6 months is established at 110 mg/day, 7–12 months: 370 mg/day; for children 1–3 years: 800 mg/day, 4–8 years: 1,000 mg/day; for adolescents: 9–13 years – 1,200 mg/day, 14–18 years 1,500 mg/day; for adults regardless of their age or sex: 1,500 mg/day. Sodium chloride ( NaCl ) contains approximately 39.34% of elemental sodium ( Na )

1444-421: A roughly ten-times higher concentration of sodium ions outside the cell than inside. In nerve cells , the sudden flow of sodium ions into the cell through voltage-gated sodium channels enables transmission of a nerve impulse in a process called the action potential . Sodium at standard temperature and pressure is a soft silvery metal that combines with oxygen in the air, forming sodium oxides . Bulk sodium

1520-461: A slight radiation hazard; the radioactivity stops within a few days after removal from the reactor. If a reactor needs to be shut down frequently, NaK is used. Because NaK is a liquid at room temperature, the coolant does not solidify in the pipes. In this case, the pyrophoricity of potassium requires extra precautions to prevent and detect leaks. Another heat transfer application is poppet valves in high-performance internal combustion engines;

1596-408: A strong reducing agent, forms upon mixing Na and naphthalene in ethereal solutions. Sodium forms alloys with many metals, such as potassium, calcium , lead , and the group 11 and 12 elements. Sodium and potassium form KNa 2 and NaK . NaK is 40–90% potassium and it is liquid at ambient temperature . It is an excellent thermal and electrical conductor. Sodium-calcium alloys are by-products of

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1672-476: A synergistic effect. "Super salt" is a mixture of 9 parts salt, to one part MSG and 0.1 parts disodium ribonucleotides (a mixture of disodium inosinate and disodium guanylate ). MSG is generally recognized as safe to eat. A popular belief is that MSG can cause headaches and other feelings of discomfort, but blinded tests have not provided strong evidence of this. International bodies governing food additives currently consider MSG safe for human consumption as

1748-448: A unique taste not yet scientifically described (not sweet, salty, sour, or bitter). To determine which glutamate could result in the taste of umami , he studied the taste properties of numerous glutamate salts such as calcium, potassium, ammonium, and magnesium glutamate. Of these salts, monosodium glutamate was the most soluble and palatable, as well as the easiest to crystallize. Ikeda called his product "monosodium glutamate" and submitted

1824-440: A variety of programs and services to its member societies to support their individual members, including advocating for federal funding for their research, hosting scientific conferences and meetings to share their research findings, publishing scientific journals to promote their research, working to create a diverse and representative workforce in the biological and biomedical sciences, and celebrating researchers’ efforts to advance

1900-437: Is a popular misconception that MSG can cause headaches and other feelings of discomfort, known as " Chinese restaurant syndrome ". Several 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

1976-591: Is about one-third of that in sodium chloride (39.34%), due to the greater mass of the glutamate counterion. Although other salts of glutamate have been used in low-salt soups, they are less palatable than MSG. Food scientist Steve Witherly noted in 2017 that MSG may promote healthy eating by enhancing the flavor of food such as kale while reducing the use of salt . The ribonucleotide food additives disodium inosinate (E631) and disodium guanylate (E627), as well as conventional salt, are usually used with monosodium glutamate-containing ingredients as they seem to have

2052-461: Is an alkali metal , being in group 1 of the periodic table. Its only stable isotope is Na. The free metal does not occur in nature and must be prepared from compounds. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars , sodalite , and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by

2128-457: Is dissolved in ammonia solution, it can be used to reduce alkynes to trans- alkenes . Lasers emitting light at the sodium D line are used to create artificial laser guide stars that assist in the adaptive optics for land-based visible-light telescopes. Liquid sodium is used as a heat transfer fluid in sodium-cooled fast reactors because it has the high thermal conductivity and low neutron absorption cross section required to achieve

2204-401: 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 down during cooking and, like other amino acids, will exhibit a Maillard reaction (browning) in the presence of sugars at very high temperatures. Glutamic acid was discovered and identified in 1866 by

2280-456: Is less electropositive than sodium, no calcium will be deposited at the cathode. This method is less expensive than the previous Castner process (the electrolysis of sodium hydroxide ). If sodium of high purity is required, it can be distilled once or several times. The market for sodium is volatile due to the difficulty in its storage and shipping; it must be stored under a dry inert gas atmosphere or anhydrous mineral oil to prevent

2356-531: Is seen in any whose surfaces are cool enough for sodium to exist in atomic form (rather than ionised). This corresponds to stars of roughly F-type and cooler. Many other stars appear to have a sodium absorption line, but this is actually caused by gas in the foreground interstellar medium . The two can be distinguished via high-resolution spectroscopy, because interstellar lines are much narrower than those broadened by stellar rotation . Sodium has also been detected in numerous Solar System environments, including

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2432-462: Is stable. Na is created in the carbon-burning process in stars by fusing two carbon atoms together; this requires temperatures above 600 megakelvins and a star of at least three solar masses. Two radioactive , cosmogenic isotopes are the byproduct of cosmic ray spallation : Na has a half-life of 2.6 years and Na, a half-life of 15 hours; all other isotopes have a half-life of less than one minute. Two nuclear isomers have been discovered,

2508-549: Is the principal source of sodium ( Na ) in the diet, and is used as seasoning and preservative in such commodities as pickled preserves and jerky ; for Americans, most sodium chloride comes from processed foods . Other sources of sodium are its natural occurrence in food and such food additives as monosodium glutamate (MSG), sodium nitrite , sodium saccharin, baking soda (sodium bicarbonate), and sodium benzoate . The U.S. Institute of Medicine set its tolerable upper intake level for sodium at 2.3 grams per day, but

2584-622: Is to melt them together and another is to deposit sodium electrolytically on molten lead cathodes. NaPb 3 , NaPb, Na 9 Pb 4 , Na 5 Pb 2 , and Na 15 Pb 4 are some of the known sodium-lead alloys. Sodium also forms alloys with gold (NaAu 2 ) and silver (NaAg 2 ). Group 12 metals ( zinc , cadmium and mercury ) are known to make alloys with sodium. NaZn 13 and NaCd 2 are alloys of zinc and cadmium. Sodium and mercury form NaHg, NaHg 4 , NaHg 2 , Na 3 Hg 2 , and Na 3 Hg. Because of its importance in human health, salt has long been an important commodity. In medieval Europe,

2660-628: Is usually ionically bonded to water and anions and is viewed as a hard Lewis acid . Most soaps are sodium salts of fatty acids . Sodium soaps have a higher melting temperature (and seem "harder") than potassium soaps. Like all the alkali metals , sodium reacts exothermically with water. The reaction produces caustic soda ( sodium hydroxide ) and flammable hydrogen gas. When burned in air, it forms primarily sodium peroxide with some sodium oxide . Sodium tends to form water-soluble compounds, such as halides , sulfates , nitrates , carboxylates and carbonates . The main aqueous species are

2736-469: Is usually stored in oil or an inert gas. Sodium metal can be easily cut with a knife. It is a good conductor of electricity and heat. Due to having low atomic mass and large atomic radius, sodium is third-least dense of all elemental metals and is one of only three metals that can float on water, the other two being lithium and potassium. The melting (98 °C) and boiling (883 °C) points of sodium are lower than those of lithium but higher than those of

2812-558: The HS code 29224220 and the E number E621. Pure MSG is reported not to have 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 optimal concentration varies by food; in clear soup , the "pleasure score" rapidly falls with the addition of more than one gram of MSG per 100   mL. The sodium content (in mass percent ) of MSG, 12.28%,

2888-595: The Sun . The line was first studied in 1814 by Joseph von Fraunhofer during his investigation of the lines in the solar spectrum, now known as the Fraunhofer lines . Fraunhofer named it the "D" line, although it is now known to actually be a group of closely spaced lines split by a fine and hyperfine structure . The strength of the D ;line allows its detection in many other astronomical environments. In stars, it

2964-472: The electrolysis of sodium hydroxide . In 1809, the German physicist and chemist Ludwig Wilhelm Gilbert proposed the names Natronium for Humphry Davy's "sodium" and Kalium for Davy's "potassium". The chemical abbreviation for sodium was first published in 1814 by Jöns Jakob Berzelius in his system of atomic symbols, and is an abbreviation of the element's Neo-Latin name natrium , which refers to

3040-467: The exospheres of Mercury and the Moon , and numerous other bodies. Some comets have a sodium tail , which was first detected in observations of Comet Hale–Bopp in 1997. Sodium has even been detected in the atmospheres of some extrasolar planets via transit spectroscopy . Employed in rather specialized applications, about 100,000 tonnes of metallic sodium are produced annually. Metallic sodium

3116-558: The sixth most abundant element on Earth and the fourth most abundant metal, behind aluminium , iron , calcium , and magnesium and ahead of potassium. Sodium's estimated oceanic abundance is 10.8 grams per liter. Because of its high reactivity, it is never found as a pure element. It is found in many minerals, some very soluble, such as halite and natron , others much less soluble, such as amphibole and zeolite . The insolubility of certain sodium minerals such as cryolite and feldspar arises from their polymeric anions, which in

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3192-679: The 1995 Federation of American Societies for Experimental Biology (FASEB) – concluded, "there may be a small number of unstable asthmatics who respond to doses of 1.5–2.5 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 has been produced by three methods: hydrolysis of vegetable proteins with hydrochloric acid to disrupt peptide bonds (1909–1962); direct chemical synthesis with acrylonitrile (1962–1973), and bacterial fermentation (the current method). Wheat gluten

3268-523: The Egyptian natron , a natural mineral salt mainly consisting of hydrated sodium carbonate. Natron historically had several important industrial and household uses, later eclipsed by other sodium compounds. Sodium imparts an intense yellow color to flames. As early as 1860, Kirchhoff and Bunsen noted the high sensitivity of a sodium flame test , and stated in Annalen der Physik und Chemie : In

3344-621: 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 590mg/day, with extreme users (97.5th percentile consumers) consuming 2,330mg/day" (Rhodes et al. 1991). In a highly seasoned restaurant meal, intakes as high as 5,000 mg or more may be possible (Yang et al. 1997). When very large doses of MSG (>5 g MSG in

3420-504: The German chemist Karl Heinrich Ritthausen , who treated wheat gluten (for which it was named) with sulfuric acid . Kikunae Ikeda of Tokyo Imperial University isolated glutamic acid as a taste substance in 1908 from the seaweed Laminaria japonica ( kombu ) by aqueous extraction and crystallization, calling its taste umami ("delicious taste"). Ikeda noticed that dashi , the Japanese broth of katsuobushi and kombu , had

3496-499: The National Biomedical Research Foundation, both names Steel claimed to have invented. Kwok's children, his colleague at the research foundation, and the son of his boss there confirmed that Robert Ho Man Kwok, who had died in 2014, wrote this letter. When told this about Kwok's family, Steel's daughter Anna was not very surprised that the story her late father had told so many times over the years

3572-477: 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 . High quality evidence has failed to demonstrate a relationship between the MSG symptom complex and actual MSG consumption. No association has been demonstrated, and the few responses were inconsistent. No symptoms were observed when MSG

3648-469: The action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans. Sodium was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide . Among many other useful sodium compounds, sodium hydroxide ( lye ) is used in soap manufacture , and sodium chloride ( edible salt ) is a de-icing agent and

3724-689: The aquo complexes [Na(H 2 O) n ] , where n = 4–8; with n = 6 indicated from X-ray diffraction data and computer simulations. Direct precipitation of sodium salts from aqueous solutions is rare because sodium salts typically have a high affinity for water. An exception is sodium bismuthate (NaBiO 3 ), which is insoluble in cold water and decomposes in hot water. Because of the high solubility of its compounds, sodium salts are usually isolated as solids by evaporation or by precipitation with an organic antisolvent, such as ethanol ; for example, only 0.35 g/L of sodium chloride will dissolve in ethanol. A crown ether such as 15-crown-5 may be used as

3800-715: The average person in the United States consumes 3.4 grams per day. The American Heart Association recommends no more than 1.5 g of sodium per day. The Committee to Review the Dietary Reference Intakes for Sodium and Potassium, which is part of the National Academies of Sciences, Engineering, and Medicine, has determined that there isn't enough evidence from research studies to establish Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) values for sodium. As

3876-505: The biological and biomedical sciences through an awards program. Membership in FASEB is limited to scientific societies. Societies are either Full or Associate members. Each member society shares a common vision for the advancement of research and education in the biological and biomedical sciences. Full Members Associate Members FASEB publishes two open access research journals: Both journals are peer-reviewed and cover research in

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3952-423: The case of feldspar is a polysilicate. In the universe, sodium is the 15th most abundant element with a 20,000 parts-per-billion abundance, making sodium 0.002% of the total atoms in the universe. Atomic sodium has a very strong spectral line in the yellow-orange part of the spectrum (the same line as is used in sodium-vapour street lights ). This appears as an absorption line in many types of stars, including

4028-532: The diet does not increase glutamate in the brain or affect brain function. A 1995 report from the Federation of American Societies for Experimental Biology (FASEB) for the United States Food and Drug Administration (FDA) concluded that MSG is safe when "eaten at customary levels" and, although a subgroup of otherwise-healthy individuals develop an MSG symptom complex when exposed to 3 g of MSG in

4104-431: The discursive uptake in media, the conversations were recontextualized as legitimate while the supposed race-based motivations of the humor were not parsed. In January 2018, Howard Steel claimed to Jennifer Lemesurier of Colgate University (who had published an article on the letter) that the letter was actually a prank submission by him under the pseudonym Ho Man Kwok. However, there was a Robert Ho Man Kwok who worked at

4180-431: The electrolytic production of sodium from a binary salt mixture of NaCl-CaCl 2 and ternary mixture NaCl-CaCl 2 -BaCl 2 . Calcium is only partially miscible with sodium, and the 1–2% of it dissolved in the sodium obtained from said mixtures can be precipitated by cooling to 120 °C and filtering. In a liquid state, sodium is completely miscible with lead. There are several methods to make sodium-lead alloys. One

4256-540: The food-additive class name (e.g. "flavour enhancer"), followed by the name of the additive ("MSG") or its International Numbering System (INS) number, 621. The Punjab Food Authority banned Ajinomoto, commonly known as Chinese salt, which contains MSG, from being used in food products in the Punjab Province of Pakistan in January 2018. The following are alternative names for MSG: A controversy surrounding

4332-420: The formation of a surface layer of sodium oxide or sodium superoxide . Though metallic sodium has some important uses, the major applications for sodium use compounds; millions of tons of sodium chloride , hydroxide , and carbonate are produced annually. Sodium chloride is extensively used for anti-icing and de-icing and as a preservative; examples of the uses of sodium bicarbonate include baking, as

4408-435: The heavier alkali metals potassium, rubidium, and caesium, following periodic trends down the group. These properties change dramatically at elevated pressures: at 1.5  Mbar , the color changes from silvery metallic to black; at 1.9 Mbar the material becomes transparent with a red color; and at 3 Mbar, sodium is a clear and transparent solid. All of these high-pressure allotropes are insulators and electrides . In

4484-491: The industrial production of MSG, keeping up with demand. The product, after filtration, concentration, acidification, and crystallization, is glutamate, sodium ions, and water. The compound is usually 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 3 )-( CH 2 ) 2 -COO. In solution it dissociates into glutamate and sodium ions. MSG

4560-517: The longer-lived one being Na with a half-life of around 20.2 milliseconds. Acute neutron radiation, as from a nuclear criticality accident , converts some of the stable Na in human blood to Na; the neutron radiation dosage of a victim can be calculated by measuring the concentration of Na relative to Na. Sodium atoms have 11 electrons, one more than the stable configuration of the noble gas neon . The first and second ionization energies are 495.8 kJ/mol and 4562 kJ/mol, respectively. As

4636-466: The need for large quantities of sodium. A related process based on the reduction of sodium hydroxide was developed in 1886. Sodium is now produced commercially through the electrolysis of molten sodium chloride (common salt), based on a process patented in 1924. This is done in a Downs cell in which the NaCl is mixed with calcium chloride to lower the melting point below 700 °C. As calcium

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4712-441: The positive charge counterbalanced by electrons as anions ; cryptands permit the isolation of these complexes as crystalline solids. Sodium forms complexes with crown ethers, cryptands and other ligands. For example, 15-crown-5 has a high affinity for sodium because the cavity size of 15-crown-5 is 1.7–2.2 Å, which is enough to fit the sodium ion (1.9 Å). Cryptands, like crown ethers and other ionophores , also have

4788-456: The pressure increases. By itself or with potassium , sodium is a desiccant ; it gives an intense blue coloration with benzophenone when the desiccate is dry. In organic synthesis , sodium is used in various reactions such as the Birch reduction , and the sodium fusion test is conducted to qualitatively analyse compounds. Sodium reacts with alcohols and gives alkoxides , and when sodium

4864-510: The reaction of 130 subjects with a reported sensitivity to MSG. Multiple trials were performed, with subjects exhibiting at least two symptoms continuing. Two people out of the 130 responded to all 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 have yielded mixed results. Although several studies have investigated anecdotal links between MSG and asthma , current evidence does not support

4940-500: The safety of MSG began on 4 April 1968, when Robert Ho Man Kwok wrote a letter to the New England Journal of Medicine , coining the term "Chinese restaurant syndrome". In his letter, Kwok suggested several possible causes before he nominated MSG for his symptoms. This letter was initially met with insider satirical responses, some using race as prop for humorous effect, within the medical community. Some claimed that during

5016-435: The term "spices and flavorings". However, the term " natural flavor/s " is used by the food industry for glutamic acid (chemically similar to MSG, lacking only the sodium ion ). The Food and Drug Administration (FDA) does not require disclosure of components and amounts of " natural flavor/s ." Standard 1.2.4 of the Australia and New Zealand Food Standards Code requires MSG to be labeled in packaged foods. The label must have

5092-615: The total mass. This means that 1 gram of sodium chloride contains approximately 393.4 mg of elemental sodium. For example, to find out how much sodium chloride contains 1500 mg of elemental sodium (the value of 1500 mg sodium is the adequate intake (AI) for an adult), we can use the proportion: Solving for x gives us the amount of sodium chloride that contains 1500 mg of elemental sodium: This mean that 3812.91 mg of sodium chloride contain 1500 mg of elemental sodium. Federation of American Societies for Experimental Biology Founded in 1912, FASEB

5168-476: The valve stems are partially filled with sodium and work as a heat pipe to cool the valves. In humans, sodium is an essential mineral that regulates blood volume, blood pressure, osmotic equilibrium and pH . The minimum physiological requirement for sodium is estimated to range from about 120 milligrams per day in newborns to 500 milligrams per day over the age of 10. Sodium chloride , also known as edible salt or table salt (chemical formula NaCl ),

5244-649: Was caused by "xenophobic" or "racist" biases. Food historian Ian Mosby wrote that fear of MSG in Chinese food is part of the US's long history of viewing the "exotic" cuisine of Asia as dangerous and dirty. In 2016, Anthony Bourdain stated in Parts Unknown that "I think MSG is good stuff ... You know what causes Chinese restaurant syndrome? Racism." In 2020, Ajinomoto , the first corporation to mass-produce MSG for consumers and today its leading manufacturer, launched

5320-442: Was established to provide a forum for biological and biomedical researchers enabling them to hold educational meetings, develop publications, and disseminate biological research results. FASEB currently comprises 22 scientific societies. As a federation, FASEB's collective mission is to advance health and well-being by promoting research and education in the biological and biomedical sciences. To advance its mission, FASEB provides

5396-424: Was false. He liked to prank people. Researchers, doctors, and activists have tied the controversy about MSG to xenophobia and racism against Chinese culture, saying that East Asian cuisine is being targeted while the widespread use of MSG in other ultra-processed foods has not been stigmatized. These activists have claimed that the perpetuation of the negative image of MSG through the Chinese restaurant syndrome

5472-560: Was first prepared in 1908 by Japanese biochemist Kikunae Ikeda , who tried to isolate and duplicate the savory taste of kombu , an edible seaweed used as a broth ( dashi ) for Japanese cuisine . MSG balances, blends, and rounds the perception of other tastes. MSG, along with disodium ribonucleotides , is commonly used and found in stock (bouillon) cubes , soups , ramen , gravy , stews , condiments , savory snacks , etc. The U.S. Food and Drug Administration has given MSG its generally recognized as safe (GRAS) designation. It

5548-519: Was first produced commercially in the late nineteenth century by carbothermal reduction of sodium carbonate at 1100 °C, as the first step of the Deville process for the production of aluminium: The high demand for aluminium created the need for the production of sodium. The introduction of the Hall–Héroult process for the production of aluminium by electrolysing a molten salt bath ended

5624-478: Was originally used for hydrolysis because it contains more than 30 g of glutamate and glutamine per 100 g of protein. As demand for MSG increased, chemical synthesis and fermentation were studied. The polyacrylic fiber industry began in Japan during the mid-1950s, and acrylonitrile was adopted as a base material to synthesize MSG. As of 2016, most MSG worldwide is produced by bacterial fermentation in

5700-554: Was the making of tetraethyllead and titanium metal; because of the move away from TEL and new titanium production methods, the production of sodium declined after 1970. Sodium is also used as an alloying metal, an anti-scaling agent , and as a reducing agent for metals when other materials are ineffective. Note the free element is not used as a scaling agent, ions in the water are exchanged for sodium ions. Sodium plasma ("vapor") lamps are often used for street lighting in cities, shedding light that ranges from yellow-orange to peach as

5776-410: Was used in food. Adequately controlling for experimental bias includes a blinded, placebo-controlled experimental design and administration by capsule, because of the unique aftertaste of glutamates. In a 1993 study, 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 in 2000 tested

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