Glutamates

from Wikipedia, the free encyclopedia
Glutamates
Magnesium-L-glutamate.svg
Magnesium - L -diglutamate
Monosodium L-Glutamate.svg
Mono sodium - L glutamate
Calcium diglutamate.svg
Calcium - L -diglutamate
Monopotassium L-glutamate.png
Mono potassium - L glutamate

When glutamates are esters and salts of glutamic acid , respectively. Salts of L- glutamic acid are particularly well known due to their use as flavor enhancers in foods. The simple sodium salt is called monosodium glutamate (E 621) and is the most widely used. Monopotassium glutamate (E 622), calcium diglutamate (E 623), monoammonium glutamate (E 624), magnesium diglutamate (E 625) are also permitted . Glutamates are approved as additives by the additive approval regulation for most foods up to a maximum amount of 10 g / kg (calculated as glutamic acid).

Use as a flavor enhancer

Glutamic acid was first isolated from wheat gluten in 1866 by the German chemist Heinrich Ritthausen . In 1908, the Japanese researcher Kikunae Ikeda discovered its importance for taste quality. He investigated the cause of the special good taste of cheese, meat and tomatoes, which is not covered by the four familiar flavors sweet , sour , salty and bitter . He was able to extract kombu glutamate from the seaweed used in the kitchen in Japan and prove that glutamate is responsible for the special umami taste. Together with the industrialist Saburôsuke Suzuki, he later founded the Ajinomoto company to market his discovery . Today monosodium glutamate is produced biotechnologically ( fermentation ) with the help of the bacterium Corynebacterium glutamicum (1.7 million tons per year) , especially in Southeast Asia .

Health assessments

The amino acid L- glutamic acid is found naturally in almost all protein-containing foods . With a normal mixed diet, the daily glutamate intake is therefore 8–12 g.

Based on scientific studies, the DFG Senate Commission is of the opinion that glutamate can be assessed as harmless to health (according to a statement from 2005).

In the case of hypersensitivity, it is suspected that monosodium glutamate (MNG) is the cause of the Chinese restaurant syndrome . Although it cannot yet be ruled out that there are people who react sensitively to MSG, in a double-blind study conducted in 1987 by the Expert Panel of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO), the Joint FAO / WHO Committee of Experts on Food additives (JECFA) in people who say they suffer from so-called Chinese restaurant syndrome are not identified as the cause.

There are indications that disorders of endogenous glutamate metabolism with chronic diseases such as Alzheimer's disease , Parkinson's disease , Huntington's disease and amyotrophic lateral sclerosis are (ALS) in the context, but taken with food glutamate (exogenous glutamate) this seems to play no role . A diet rich in glutamate has no influence on the cerebral L -glutamate concentration, and the effect on the blood glutamate level also corresponds to the normal physiological fluctuation ranges. A connection between glutamate and obesity is also being investigated, but so far without any meaningful evidence. In a study from 2010 it was shown that an increased level of glutamate in the blood serum is associated with aggressive prostate tumors .

Web links

Commons : Glutamate  - Collection of images, videos and audio files

literature

  • Silvia Ortega-Gutiérrez: Excitotoxicity: Deadly stimuli . In: Brain & Mind . No. 4 , 2007 ( online ).
  • Kathi Dittrich: Glutamate - Harmless or Neurotoxic? In: UGB forum . No. 2 , 2004, p. 100-101 ( PDF ).

Individual evidence

  1. ↑ a b Text of the Additive Admissions Ordinance, Annex 4 (to Section 5, Paragraph 1 and Section 7) Limited additives .
  2. ↑ Addison Ault: The Monosodium Glutamate Story: The Commercial Production of MSG and Other Amino Acid. In: Journal of Chemical Education . Volume 81, No. 3, March 2004, pp. 347-355, doi: 10.1021 / ed081p347 .
  3. ↑ German Society for Nutrition : DGEInfo 10/2005 - Research, Clinic and Practice. Glutamate - no new recommendations necessary ( Memento from August 3, 2014 in the Internet Archive )
  4. ↑ a b German Nutrition Society DGE-aktuell 08/2003 of June 10, 2003 Is the flavor enhancer glutamate harmful to health? ( Memento from February 22, 2014 in the Internet Archive )
  5. ^ R. Walker, JR Lupien: The safety evaluation of monosodium glutamate . In: The Journal of Nutrition . tape 130 , 4S Suppl. 2000, p. 1049S – 1052S , PMID 10736380 ( online - free full text).
  6. ↑ G. Eisenbrand: Opinion on the potential involvement of oral glutamate intake in chronic neurodegenerative diseases. In: DFG - Senate Commission for the Assessment of the Harmlessness of Food . April 2005, page 11 (PDF; 143 kB).
  7. ↑ Martina Melzer: Glutamate flavor enhancer: harmless or unhealthy? In: Apothekenumschau . October 21, 2016. Retrieved July 29, 2017 .
  8. ↑ Glutamate as a tumor motor? In: Doctors newspaper online. January 3, 2013, accessed July 29, 2017.