Glutamic acid was discovered and identified in 1866 by 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 Ikeda noticed that dashi, the Japanese broth of katsuobushi and kombu, had a unique taste not yet scientifically described (not sweet, salty, sour, or bitter). To verify that ionized glutamate was responsible for umami, he studied the taste properties of glutamate salts: calcium, potassium, ammonium, and magnesium glutamate. All these salts elicited umamiand a metallic taste due to the other minerals. Of them, sodium glutamate was the most soluble, most palatable, and easiest to crystallize. Ikeda called his product “monosodium glutamate”, and submitted a patent to produce MSG;the Suzuki brothers began commercial production of MSG in 1909 as Aji-no-moto “essence of taste”). Society and culture It has been suggested that a fear of MSG may reflect anti-Asian racism, with MSG being seen as an “Oriental”, alien arrival in Western cooking, likely to be dangerous. Food critic Jeffrey Steingarten argued that fear of MSG should be seen as a Western-centric mindset, lacking awareness of its common use in Far Eastern cooking without apparent problems: “If MSG is a problem, why doesn’t everyone in China have a headache?” Use
Pure MSG is reported to not have a 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 optimum 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%, is about one-third of that in sodium chloride (39%), 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. Safety A popular belief is that MSG can cause headaches and other feelings of discomfort but double-blind tests have found no good evidence to support this. MSG has been used for more than 100 years to season food, with a number of studies conducted on its safety. Consumption and manufacture of high-salt and high-glutamate foods, which contain both sodium and glutamate, stretch back far longer, with evidence of cheese manufacture as early as 5,500 BC. International and national bodies governing food additives currently consider MSG safe for human consumption as 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 (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 level of glutamic acid in foods are not toxicological concerns in humans.
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 the absence of food, MSG as a cause has not been established because the symptom reports are anecdotal.
According to the report, no data support the role of glutamate in chronic disease. A controlled, double-blind, multiple-location clinical trial failed to demonstrate a relationship between the MSG symptom complex and actual MSG consumption. No statistical association has been demonstrated, and the few responses were inconsistent. No symptoms were observed when MSG was administered with food.