Monosodium glutamate
Names | |
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IUPAC name
Sodium 2-aminopentanedioate
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Identifiers | |
3D model (
JSmol ) |
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ChemSpider | |
ECHA InfoCard
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100.005.035 |
EC Number |
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E number | E621 (flavour enhancer) |
PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
C5H8NO4Na | |
Molar mass | 169.111 g/mol (anhydrous), 187.127 g/mol (monohydrate) |
Appearance | White crystalline powder |
Density | 322 |
Melting point | 232 °C (450 °F; 505 K) |
740 g/L | |
Hazards | |
NFPA 704 (fire diamond) | |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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16600 mg/kg (oral, rat)[1] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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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.[2][3][4] MSG is used in cooking as a flavor enhancer with a savory taste that intensifies the meaty, savory flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups.[5][6]
MSG was first prepared in 1908 by Japanese
, etc.The U.S.
Use
Pure MSG is reported not to have a highly pleasant taste until it is combined with a savory
The sodium content (in
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 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).[18]
Safety
MSG is generally recognized as safe to eat.[2][19][20] A popular belief is that MSG can cause headaches and other feelings of discomfort, but blinded tests have not provided strong evidence of this.[10] International bodies governing food additives currently consider MSG safe for human consumption as a flavor enhancer.[21] 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 (LD50) is between 15 and 18 g/kg body weight in rats and mice, respectively, five times the LD50 of sodium chloride (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.[21] Specifically MSG in the diet does not increase glutamate in the brain or affect brain function.[22]
A 1995 report from the
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 was used in food.[24][25][26][27]
Adequately controlling for experimental bias includes a blinded,
Studies exploring MSG's role in obesity have yielded mixed results.[29][30]
Although several studies have investigated anecdotal links between MSG and asthma, current evidence does not support a causal association.[31]
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 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."[32][33]
However, 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 590 mg/day, with extreme users (97.5th percentile consumers) consuming 2,330 mg/day" (Rhodes et al. 1991).
Production
MSG has been produced by three methods:
As of 2016, most MSG worldwide is produced by bacterial fermentation in 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.[38]
The conversion yield and production rate (from sugars to glutamate) continues to improve in the industrial production of MSG, keeping up with demand.[36] The product, after filtration, concentration, acidification, and crystallization, is glutamate, sodium, and water.
Chemical properties
The compound is usually available as the
and glutamate anions in zwitterionic form, −OOC-CH(NH+
3)-(CH
2)2-COO−.[39] In solution it dissociates
MSG is freely soluble in water, but it is not
History
Society and culture
Regulations
United States
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
Australia and New Zealand
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 the food-additive class name (e.g. "flavour enhancer"), followed by the name of the additive ("MSG") or its
Pakistan
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.[50]
Names
The following are alternative names for MSG:[51][52]
- Chemical names and identifiers
- Monosodium glutamate or sodium glutamate
- Sodium 2-aminopentanedioate
- Glutamic acid, monosodium salt, monohydrate
- L-Glutamic acid, monosodium salt, monohydrate
- L-Monosodium glutamate monohydrate
- Monosodium L-glutamate monohydrate
- MSG monohydrate
- Sodium glutamate monohydrate
- UNII-W81N5U6R6U
- Flavour enhancer E621
- Trade names
Stigma in Western countries
Origin
A controversy surrounding the safety of MSG began on 4 April 1968, when Robert Ho Man Kwok wrote a letter to the
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.[59][61] However, there was a Robert Ho Man Kwok who worked at the National Biomedical Research Foundation, both names Steel claimed to have invented.[61] 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.[61] 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 was false. He liked to prank people.[61]
The claims of 'Chinese restaurant syndrome' have the same symptoms as hypernatremia, so it may actually be salt poisoning.[62]
Reactions
Researchers, doctors, and activists have tied the controversy about MSG to xenophobia and racism against Chinese culture,[63][64][65][66][67] saying that East Asian cuisine is being targeted while the widespread use of MSG in other ultra-processed food hasn't been stigmatized.[68] These activists have claimed that the perpetuation of the negative image of MSG through the Chinese restaurant syndrome was caused by "xenophobic" or "racist" biases.[69][70]
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 2020,
See also
References
- PMID 5059711.
- ^ a b "Questions and Answers on Monosodium glutamate (MSG)". www.fda.gov. U.S. Food and Drug Administration. 19 November 2012.
MSG occurs naturally in many foods, such as tomatoes and cheeses
- ^ "Monosodium glutamate (MSG) – Questions and Answers". Government of Canada. 29 January 2008. Retrieved 20 May 2018.
- S2CID 3141583.
- PMID 12438213.
- ^ Hayward, Tim (22 May 2015). "OMG I love MSG". Financial Times. Nikkei. Archived from the original on 10 December 2022. Retrieved 5 March 2016.
- ^ PMID 10736352.
- S2CID 20980527.
- ^ a b "Questions and Answers on Monosodium glutamate (MSG)". U.S. Food and Drug Administration. 19 November 2012. Retrieved 4 February 2014.
- ^ PMID 27189588.
- ^ Wei, Will (16 June 2014). The Truth Behind Notorious Flavor Enhancer MSG. Business Insider (Podcast). Retrieved 13 November 2017.
- ^ "Current EU approved additives and their E Numbers". Food.gov.uk. 26 November 2010. Retrieved 30 January 2012.
- PMID 19571217.
- ^ Kawamura Y, Kare MR, eds. (1987). Umami: a basic taste. New York, NY: Marcel Dekker Inc.
- .
- PMID 12032651.
- ^ Lubin, Gus (2 February 2017). "Everyone should cook with MSG, says food scientist". Business Insider. Retrieved 27 January 2019.
- ^ "Everyone should cook with MSG, says food scientist". Business Insider.
- ^ "MSG in food". www.foodstandards.gov.au. Food Standards Australia New Zealand. October 2017.
- ^ Barry-Jester, Anna Maria (8 January 2016). "How MSG Got A Bad Rap: Flawed Science And Xenophobia".
- ^ PMID 10736380.
- PMID 30508818.
- S2CID 3945714.
- ^ S2CID 21084909.
- PMID 10736382. Archived from the originalon 14 January 2012.
- ^ PMID 8282275.
- PMID 10597625.
- S2CID 20044934.
- PMID 20370941.
- ^ Bakalar, Nicholas (25 August 2008). "Nutrition: MSG Use is Linked to Obesity". The New York Times. Retrieved 10 November 2010.
Consumption of monosodium glutamate, or MSG, the widely used food additive, may increase the likelihood of being overweight, a new study says.
- ^
Stevenson, D. D. (2000). "Monosodium glutamate and asthma". J. Nutr. 130 (4S Suppl): 1067S–73S. PMID 10736384.
- ^ )
- ^ "Monosodium glutamate search". FoodStandards.gov.au. Food Standards Australia New Zealand, Health Minister Chair, Peter Dutton MP. Retrieved 13 August 2014.
- PMID 1818840. Retrieved 25 May 2023.
- PMID 9215242. Retrieved 25 May 2023.
- ^ PMID 19640955.
- .
- .
- .
- ^ Win. C., ed. (1995). Principles of Biochemistry. Boston, MA: Brown Pub Co.
- ^ .
- ^ Plimmer, R.H.A. (1912) [1908]. R.H.A. Plimmer; F.G. Hopkins (eds.). The Chemical Constitution of the Protein. Monographs on biochemistry. Vol. Part I. Analysis (2nd ed.). London: Longmans, Green and Co. p. 114. Retrieved 3 June 2012.
- ^ PMID 12438211.
- ^ Renton, Alex (10 July 2005). "If MSG is so bad for you, why doesn't everyone in Asia have a headache?". The Guardian.
- ^ "Kikunae Ikeda". Umami Information Center. Retrieved 8 February 2022.
- ^ Ikeda K (1908). "A production method of seasoning mainly consists of salt of L-glutamic acid". Japanese Patent 14804.
- PMID 19640953.
- ^ "CFR – Code of Federal Regulations Title 21, Vol 6, Part 501, Subpart B – Specific Animal Food Labeling Requirements". FDA.gov. U.S. Food and Drug Administration. Retrieved 13 August 2014.
- ^ "Standard 1.2.4 Labelling of Ingredients". Food Standards Code. Food Standards Australia New Zealand. Archived from the original on 21 August 2010. Retrieved 15 May 2010.
- ^ "Punjab Food Authority bans Chinese salt after scientific panel finds it hazardous for health". Dawn. 15 January 2018. Retrieved 15 January 2018.
- ^ Singh, K. K.; Desai, Pinakin. "Glutamate Chemical". TriveniInterChem.com. Riveni InterChem of Triveni Chemicals, manufacturer & supplier of industrial chemicals, India. Archived from the original on 2 July 2017. Retrieved 11 August 2014.
- ^ Desmo Exports Limited, Chemical Manufacturers and Importers of India (2011). "Monosodium Glutamate (MSG)". DesmoExports.com. Desmo Exports. Archived from the original on 11 June 2016. Retrieved 11 August 2014.
- ^ "Accent Flavor Enhancer". AccentFlavor.com. B&G Foods, Inc. Archived from the original on 17 June 2014. Retrieved 11 August 2014.
- ^ "B&G Foods, Incorporated". Grocery.com. 14 July 2011. Retrieved 13 August 2014.
- ^ "Monosodium glutamate(MSG)". Umami Global Website. Ajinomoto Co., Inc. Retrieved 30 October 2016.
- ^ "To Greet the Next 100 Years (Corporate Guide)" (PDF). AAjinomoto Co., Inc. Archived from the original (PDF) on 7 July 2014. Retrieved 13 August 2014.
- ^ Sazon Seasoning : Substitutes, Ingredients, Equivalents Archived 2 April 2015 at the Wayback Machine. GourmetSleuth. Retrieved on 4 November 2016.
- ^ .
- ^ a b Blanding, Michael (17 January 2020). "The Strange Case of Dr. Ho Man Kwok". Colgate Magazine. Retrieved 6 January 2020.
- PMID 25276867.
- ^ a b c d Sullivan, Lilly (15 February 2019). "668: The Long Fuse". This American Life. Retrieved 7 January 2020.
- PMID 5771078.
- S2CID 232143333.
- ^ Liang, Michelle (18 May 2020). "From MSG to COVID-19: The Politics of America's Fear of Chinese Food". arts.duke.edu. Retrieved 9 August 2021.
- ^ Jiang, Irene (15 January 2020). "McDonald's is testing chicken sandwiches with MSG, and people are freaking out. Here's why they shouldn't care one bit". Business Insider.
- ^ Nierenberg, Amelia (16 January 2020). "The Campaign to Redefine 'Chinese Restaurant Syndrome'". The New York Times.
- ^ Davis, River (27 April 2019). "The FDA Says It's Safe, So Feel Free to Say 'Yes' to MSG". The Wall Street Journal.
- ^ "Why Do People Freak Out About MSG in Chinese Food?". AJ+ (on YouTube). Al Jazeera Media Network. 14 August 2018. Event occurs at 0:00–1:00m and 5:20–8:30m. Archived from the original on 30 October 2021.
- .
Introduction: 'Chinese Restaurant Syndrome' as Rhetorical [...] Finally, I trace how the journalistic uptakes of this discussion, in only taking up certain medical phrases and terms, reproduce the tacit racism of this boundary policing while avowing the neutrality of medical authority.
- .
- ^ Anna Barry-Jester, "How MSG Got A Bad Rap: Flawed Science And Xenophobia," FiveThirtyEight, 8 January 2016
- ^ Yeung, Jessie (19 January 2020). "MSG in Chinese food isn't unhealthy -- you're just racist, activists say". CNN. Retrieved 21 May 2021.
- ^ Yeung, Jessie (19 January 2020). "MSG in Chinese food isn't unhealthy – you're just racist, activists say". CNN.
External links
- The Facts on Monosodium Glutamate (EUFIC) Archived 22 March 2017 at the Wayback Machine
- Dunning, Brian (17 December 2019). "Skeptoid #706: MSG: How a Friendly Flavor Became Your Enemy". Skeptoid.