Via Too Many Chefs: Umami Dearest:
At the beginning of the twentieth century, Professor Kikunae Ikeda of Tokyo Imperial University was thinking about the taste of food: “There is a taste which is common to asparagus, tomatoes, cheese and meat but which is not one of the four well-known tastes of sweet, sour, bitter and salty.”
It was in 1907 that Professor Ikeda started his experiments to identify what the source of this distinctive taste was. He knew that it was present in the “broth” made from kombu (a type of seaweed) found in traditional Japanese cuisine. Starting with a tremendous quantity of kombu broth, he succeeded in extracting crystals of glutamic acid (or glutamate). Glutamate is an amino acid, and is a building block of protein. Professor Ikeda found that glutamate had a distinctive taste, different from sweet, sour, bitter and salty, and he named it “umami.” 100 grams of dried kombu contain about 1 gram of glutamate.