Glutamic Acid (Glutamate, Glu)

Glutamic Acid is a non-essential amino acid that is found in many grains, soy sauce and other "hydrolyzed vegetable protein" products. It is also found in the seasoning MSG (Mono Sodium Glutamate) that is especially used in Chinese cuisine, but also sold in the USA as the seasoning "Accent."

Glutamate is also an excitatory neural transmitter.

According to [ajinomoto] the taste of glutamate is called Umami, and it is one of the five tastes. The other tastes are: sweet, sour [acidic], bitter [basic], and salty. "Umami means 'essence of deliciousness' in Japanese, and its taste is often described as the meaty, savory deliciousness that deepens flavor."

Some people are genetically predisposed to be sensitive to Glutamate in food.