Monosodium glutamate is the sodium salt of glutamic acid. Glutamate is a naturally occurring amino acid that is found in nearly all foods, especially high protein foods such as dairy products, meat and fish and in many vegetables.Foods often used for their flavouring properties, such as mushrooms and tomatoes, have high levels of naturally occurring glutamate.onosodium glutamate is the sodium salt of glutamic acid. Glutamate is a naturally occurring amino acid that is found in nearly all foods, especially high protein foods such as dairy products, meat and fish and in many vegetables.