Umami is a delicious flavor and one of the five basic tastes, along with sweet, sour, salty and bitter. In addition to glutamic acid, which is an amino acid, umami flavors also include inosinic acid, which is found in meat and fish and guanylic acid, abundant in mushrooms.
The synergistic effect of combining these compounds results in a stronger umami flavor.
In Japanese cuisine for example, dashi is made with glutamic acid from kombu and inosinic acid from bonito.
In Western food, soup stock is made with glutamic acid found in celery, carrot, onion and tomato and inosinic acid contained in beef, chicken and fish.