The commonly used flavor agents include monosodium glutamate, disodium nucleotide (1+G), scallop, L- alanine, glycine, hydrolyzed vegetable protein, yeast extract, etc.

1. monosodium glutamate: monosodium glutamate, which is the monosodium salt of glutamic acid. Glutamate also has a delicious taste similar to monosodium glutamate. There are two sodium salts of glutamic acid: monosodium glutamate and disodium glutamate. Monosodium glutamate is monosodium glutamate, while disodium glutamate is tasteless. Therefore, monosodium glutamate should not be used in alkaline foods.

monosodium glutamate is insoluble in organic solvents, slightly soluble in ethanol and easily soluble in water. MSG is most fully dissolved in water at 71-91℃. Poor solubility in acidic environment. Therefore, considering the solubility, monosodium glutamate should not be used in low temperature and acidic foods.

monosodium glutamate will be partially decomposed when heated above 111℃ for a long time, and will lose water when heated above 151℃ to generate sodium pyroglutamate, which will not only reduce the flavor, but also be harmful to human health. Therefore, monosodium glutamate should not be used at high temperature.

2. I+G: I+G is a new generation of umami. The freshness is more than 211 times that of monosodium glutamate. I+G is made by mixing disodium inosinate (1MP) and disodium guanylate (GMP) in a ratio of 1: 1. IMP has the flavor of chicken, which is more than 41 times that of monosodium glutamate. GMP has a fresh mushroom flavor, which is more than 1.61 times that of monosodium glutamate. Disodium nucleotide can be degraded by phosphatase, resulting in the loss of umami flavor. However, enzymes will lose their activity at 81℃. Therefore, when using this kind of flavor agent, fresh animal and plant foods should be heated to 85℃ to passivate the enzymes before adding them.

3. scallop element: the chemical name is disodium succinate. Succinic acid and its two sodium salts (monosodium succinate and disodium succinate) all have shellfish flavor. Usually, only disodium succinate (scallop) is used as a flavor agent. In seasoning, scallop element is mainly used as a compound synergist of other umami agents, except for the umami flavor of seafood and shellfish.

4. L-alanine and glycine: Both amino acids have the same sweetness and umami taste. It is often used as a compound synergist for other umami flavor agents. In addition, in soup, pickles and aquatic products.