Description
Glutamic acid is widely present in the body of animals and plants, and is a naturally occurring nutrient in food. After glutamate is eaten, 96% is absorbed in the body, and the rest is excreted in the urine after oxidation. Although glutamic acid is not an essential amino acid for the human body, it undergoes transamination with keto acids in nitrogen metabolism and can synthesize other amino acids. Glutamate has the effect of reducing toxins in the blood. When the liver function is damaged, the ammonia content in the blood increases, causing severe nitrogen metabolism disorder, leading to hepatic coma, while glutamate can work with ammonia to reduce the ammonia content in the blood. In addition, brain tissue can only oxidize glutamate, but not other amino acids. When glucose supply is insufficient, glutamine can act as an energy source for brain tissue, so glutamate is necessary to improve and maintain brain function. Sodium glutamate has a strong umami taste of meat, and monosodium glutamate can still feel umami when diluted with water to 3000 times. In addition to monosodium glutamate, the commonly used food flavoring agents also include sodium aspartate, sodium inosinate and sodium guanylate. Taking the umami of sodium glutamate as 100, the relative umami of the other three umami agents are: sodium aspartate 30 sodium inosinate 4000 sodium guanylate 16000 sodium inosinate, sodium guanylate and Sodium sulfate is used at the same time, which has a synergistic effect and can improve the umami taste, also known as freshness aid or strong monosodium glutamate. The aqueous solution of sodium glutamate is heated for a long time, which will cause water loss and become sodium pyroglutamate. For example, when a 10% aqueous solution with pH 6.9 is heated at 100 ??C for 4 hours, the content of sodium pyroglutamate is 2.1%; when heated at 115 ??C for 4 hours, the content is 5.7%. Although sodium pyroglutamate is harmless to the body, it has no umami taste, so it is generally reasonable to add it when cooking is close to or after the pot is lifted. Generally, the concentration of monosodium glutamate is about 0.2-0.5%. my country is currently one of the world’s largest producers and consumers of monosodium glutamate, and Japan is the world’s largest consumer of monosodium glutamate. After decades of research and experiments, it has been proved that monosodium glutamate is one of the important nutrients needed by the human body. It is a natural substance that exists in human food and the human body itself. The human body can fully digest and absorb monosodium glutamate after ingesting it, and then carry out normal metabolism. Therefore, in 1987, the 19th meeting of the Food Additives Regulations Committee of the Food and Agriculture Organization of the United Nations and the World Health Organization held in the Netherlands decided to abolish the regulations on limiting the amount of monosodium glutamate used in food. In addition to the above-mentioned uses of medicine and seasoning, sodium glutamate can be used as an intermediate in organic synthesis in industry, but in the world’s annual output of more than 200,000 tons, other uses account for a very small proportion.
