The History of the Fifth Taste: Umami

By Keito Orii

Do you remember that one meal you salivated over? Was it memorable because of the pleasant atmosphere or the people you had the meal with? Maybe not! The reason why the meal was scrumptious is the special and unique flavor called umami. Naturally, the environment and the family members or friends have also contributed to the meal’s impression.
Firstly, we will examine the process that the human brain detects different tastes, then we will talk about the differences between humans and other animals. Finally, we will discuss a new taste that was discovered by Japanese professor, Kikunae Ikeda.  
It is commonly known that humans can detect the five different qualities of taste. The body part that humans use to detect the taste is the tongue. On the surface of the human tongue, there are tiny sensory organs called taste buds and these buds play the most significant role in detecting flavors. However, previously, there were said to be only four tastes – sweetness, sourness, saltiness and bitterness.
People have different numbers of taste buds based on their growth and size. Adults averagely have 2000 to 4000 taste buds in total. Moreover, different living organisms contain different numbers of taste buds. For instance, a beloved animal, dogs, have about 1700 taste buds while catfish have 175000 taste buds, almost 100 times more than dogs. The number of taste buds affects how well the creature can detect the taste. Thus, when people have more taste buds compared to average, they are called supertasters. Supertasters can detect tastes more strongly and more distinctly than others. This is because taste buds have extremely sensitive hair on the surface which sends a message to the brain about how things taste. Due to the concentration of taste buds, the front and sides of the tongue are the most sensitive to tastes.
Furthermore, different parts of the tongue are sensitive to certain tastes. The front part is sensitive to sweetness, saltiness and umami, while the sides are sensitive to sourness. The back part is sensitive to bitterness. Similarly, other animals are sensitive to different tastes. For example, cats can detect the basic five qualities of tastes, but they are said to be less sensitive to sweetness and more sensitive to bitterness. This is the intriguing process of how creatures taste things.
Now that we have a better understanding of tastes, let’s talk about “umami.” The Japanese scientist, Kikunae Ikeda, discovered the fifth taste, umami in 1908. He grew up in Kyoto, Japan. He was born in a family in which all the children were scientists in different fields. Naturally, he had a passion for chemistry and graduated from the Department of Chemistry at the Imperial University of Tokyo in 1889. After that, Kikunae became an assistant in the same department in 1896.
Three years later, he studied abroad at Leipzig University in Germany, where he majored in physical chemistry on a scholarship. During this time, he was amazed by the great physique and health of the German people. Kikunae Ikeda inferred that this came from the food that they consumed. When he sampled tomatoes, cheese, and meat in Germany, he realized that they had a taste different from the well-known four basics: sourness, bitterness, sweetness, and saltiness.
This inspired him in the study of the fifth taste. In 1901, he came back to Japan and became a professor at the Imperial University of Tokyo. He felt a sense of mission to discover and invent seasonings that contain quality nutrition and are delicious for Japanese people. In 1907, a sudden hint led him to the discovery of umami. When he ate yudofu (boiled tofu) in kelp broth, he recalled the taste of the food that he ate in Germany. Soon after this realization, he began studying the kelp broth to discover the unknown flavor which he later named umami. In 1908, after numerous experiments, he succeeded in producing about 30 grams of umami substances, or glutamic acid, which gives umami taste its distinct flavor.
Ikeda also strove to make umami commonly used in the household. Through science and technology, he was able to market it as a product. To achieve this, he worked together with another Japanese businessman, Saburo Suzuki. Saburo felt sympathy and was amazed by what Ikeda was purposefully doing for Japan. They started their project in 1909 and succeeded in making a product of umami called Ajinomoto, a chemical seasoning. The business grew larger and they established a corporation called Ajinomoto Group. The discovery and production of umami impacted Japanese cuisine culture. Ajinomoto, the umami seasoning, is beloved by Japanese people as it allows the food to have more variety of tastes as well as a rich flavor. The taste of umami goes well with everything such as miso soup, pasta sauce, steak, french fries and more. These days, as the product of Ajinomoto developed over time, it has become really common in Japan and people use Ajinomoto in their daily lives. Thanks to umami, the dining experience in the world today is more memorable and salivating than ever before.