Monosodium glutamate is a kind of condiment, which is easily soluble in water, and can give fresh flavor to plant food and fragrance to meat products. Add a little monosodium glutamate to soup and vegetables, and the taste will be more delicious. The main component of monosodium glutamate is sodium glutamate, which decomposes quickly after entering the stomach. Glutamate is the product of protein decomposition, which is an amino acid and can be directly absorbed by human body. Sodium glutamate will decompose and destroy at 100℃. Therefore, cooking monosodium glutamate in soup can decompose monosodium glutamate and most of sodium glutamate. This not only loses the flavor of monosodium glutamate, but also decomposes sodium pyroglutamate with certain toxicity. So don't put monosodium glutamate in soup and vegetables for a long time. You must put the soup and vegetables after they are ready.