Western scientists long believed that the tongue contained only four types of taste receptors — sweet, salty, sour and bitter — with the sense of smell supplying the remainder of a food’s taste. In 2000, however, researchers at the University of Miami discovered that the tongue also has receptors for the chemical glutamate, and that those receptors fire only in the presence of one of the other four tastes.
In the presence of glutamate, foods gain a more pleasant flavor. The chemical occurs naturally in meats as well as in many fermented foods such as cheese, soy sauce and black bean paste. Other foods high in glutamate include Worcestershire Sauce and human breast milk.
Western scientists dubbed the fifth taste “umami,” after the Japanese word for “savory.” The term had already been used as far back as 1908, when a Tokyo chemist identified the sensation and linked it to glutamate. This led to the development of a synthetic form of glutamate that could be added directly to food: monosodium glutamate (MSG).
Because of health concerns associated with high levels of MSG consumption, many consumers choose to avoid foods with added (rather than naturally occurring) glutamate. Many have learned to look for some of the labels food manufacturers use to conceal added glutamate, including autolyzed yeast, hydrolyzed yeast, yeast extract, hydrolyzed vegetable proteins, protein isolate and soy extracts.
Now a food writer has developed a new way to add glutamate to foods, with a new flavoring product dubbed “Taste No. 5.” Made from ingredients including pulped anchovy and porcini mushrooms, tubes of the product will soon be on sale across the United Kingdom.
“I wanted to get away from the notion that umami is something of interest to scientists that no one else can really understand,” Taste No. 5 inventor Laura Santtini said.