What is MSG
Monosodium glutamate (MSG) is the sodium salt of glutamic acid, an amino acid and an important component of protein. The various forms of glutamic acid are generically referred to as "glutamates". Glutamate is a natural element found in virtually all foods such as meat, fish, poultry, milk (including mother's milk), and many vegetables. It can be found in "bound" form when linked to with other amino acids to form protein and also in "free" form when it is unlinked.
Amino Acids are important nutrients for animals which move about in search of them. Amino Acids, including glutamate, can be regarded as "attractants" for various animals. For living organisms including humans, umami, the taste represented by glutamate could be understood as the taste flag that marks the protein as a nutrient.
Glutamate is one of the most common substances in our food supply and is found in abundance in plant and animal tissues. The human body produces glutamate in muscle, brain and other organ tissues and typically contains about two kilograms of natural glutamate.
Natural Glutamate in Food (mg/100g)