In school, I was taught (not by Aristotle but a nun who knew him) that there were 4 components of taste: sweet, sour, bitter and salty. The concept of savoriness was understood by chefs but never defined well enough for science. in 1908, Japanese scientist Kikunae Ikeda identified in particular foods, and coined the term Umami, which meant pleasant savory flavor. Word still hadn’t reached my school by the 1970s but that may have been a function of the highly Irish ethnicity of the neighborhood, Regardless and eventually, Umami has become accepted universally as the 5th flavor.
One of Ikeda’s student isolated a substance called ‘5 inosine monophosphate (IMP) in stock made from dried bonito flakes. Umami was discovered in other substances as well including Monosodium Glutamate (MSG). The process of detecting umami is more subtle than the other elements of taste and this probably contributed to the slowness of science in recognizing it. Two receptors working together detect glutamic acid and create the sensation of roundness or heartiness that is Umami. This comprehension changed the way the whole world thinks about food and taste.
The scientific understanding of the cooperative or collaborative nature of receptors in taste has lead to further insights. Certain substances, garlic being the most common, enhance and lengthen the sensation of the other flavor senses, particularly umami. These have been described as mouthfulness, increasing the intensity of the taste experience. This is called Kokumi. There is considerable ongoing research, both on the scientific side as they seek further understanding of how the body receives these chemicals and from research chefs. Of particular interest is from product developers looking for meat substitutes. Kokumi will further revolutionize how we approach the science of taste.
Here is a link to a podcast that discusses some of the commercial possibilities that are opned by by understanding Kokumi as an ingredient podcast: