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 the source of this distinctive taste. He knew that it was present in the “broth” made from kelp (a type of seaweed, kombu), a traditional ingredient in Japanese cuisine. Starting with a tremendous quantity of kelp soup stock, Dr. Ikeda succeeded in extracting crystals of glutamic acid, an amino acid, and a building block of proteins. 100 grams of dried kelp contain about 1 gram of glutamate, the ionic form of glutamic acid. Professor Ikeda found that glutamate had a distinctive taste, different from sweet, sour, bitter and salty, and he named this taste “umami.”