We all have the ability to taste sweet, salty, sour, and bitter flavors through receptors found on the tongue and in the mouth. Between 2000 and 2002 scientists found that humans could also taste umami and it became firmly established as out fifth taste. There is no English word synonymous with umami. The closest description would be savory, meaty or broth-like.
Umami imparts a rich, full-bodied taste to food that aids in our enjoyment of eating. The distinctive taste of umami was first discovered in 1908 by Dr. K. Ikeda. He identified glutamate, an amino acid (protein fragment) that is abundant in dashi, a Japanese stock flavored with dried kelp. He coined the unique taste umami. Seaweed is one of the natural foods with an exceptionally high level of free glutamate.
Glutamate is a very prevalent amino acid in food. In the mouth it binds to the inside of the umami taste receptors and sends a signal to the brain that perceives the rich, bold, meaty flavor. Have you ever wondered why portobella mushrooms make such a perfect meat substitute or why you enjoy pairing ketchup with hamburgers?
Both tomatoes and mushrooms are natural sources of glutamate. Oysters, shrimp, scallops, mackerel, tuna, sardines and meat all have natural umami flavor as well as aged cheeses and fermented foods like soy sauce
