Apr 15, '22
Featured in 13th edition of Luxeat Insider

What is Umami, anyway?

A single word holds the key to the magic to so much of what we understand about the world of taste and flavour today – Umami. But what is this famous fifth taste, where do we find it, and why is it that we can’t get enough of it?

Katsuobushi (dried bonito flakes)
Katsuobushi (dried bonito flakes)

 In 1908, Professor Kikunae Ikeda of Tokyo Imperial University discovered an unidentified taste in kombu dashi (which we’ll come on to later); something not accounted for by any combination of the basic tastes of sweet, salty, bitter, and sour. He correctly identified the source of this taste as a chemical called glutamate. The taste itself, he simply dubbed “Umami.”

Professor Kikunae Ikeda
Professor Kikunae Ikeda

Umami is the fifth taste, something distinct from the previously known sweet, sour, salty, and bitter. These are unique tastes that cannot be created by mixing other tastes, and are known as the basic or ‘primary’ tastes. In scientific terms, Umami is a general term used mainly for substances combining the amino acid glutamate and/or the nucleotides inosinate and guanylate, with minerals such as sodium and potassium.

Whether something tastes delicious or not is a complex yet subjective evaluation determined by elements such as taste, aroma, texture and temperature, as well as other factors such as appearance, colour and shape of the food. It is also affected by one’s own physical condition, surrounding environment, cultural background, and previous experiences. Of these various elements, Umami in balance with the other basic tastes (sweet, sour, salty, and bitter) plays an important role in determining the deliciousness of a dish.

Dashi: The Essence of Japanese Cuisine

To start thinking about what Umami really is, we inevitably come to dashi – one of it’s purest forms. Dashi is, in simple terms, a liquid stock that forms the basis of so much of Japanese cuisine.

Despite its hidden role, dashi could be said to be the heart of Japanese cuisine, not because of the prominence of its own flavour but because of the way it enhances and harmonises the flavours of other ingredients. The secret of Japanese cuisine is the art of enhancing and harmonising.

Dashi differs from other kinds of stock in that rather than using simple ingredients boiled over a long period, as is the case with Western bouillon, it uses carefully prepared ingredients, patiently matured, which are only soaked in water or heated briefly so as to extract nothing but the very essence of the ingredients’ flavour. Although Japanese cuisine is rich in diversity and visually attractive, this is one deceptively simple element, one whose underlying appeal is not apparent to the eye.

Dashi most commonly utilises a combination of kombu (kelp seaweed) and katsuobushi (dried bonito flakes), but other ingredients used to make dashi are shiitake mushrooms and niboshi (small dried fish). Essentially, everything is done to maximise the Umami. Dashi-making has evolved over a long period of time. Boiling is known to have been used in Japanese cooking since the Jomon period (c. 13,000–300 BC), and the stock from shellfish and fish bones was used to flavour other dishes.

Japanese dried kelp (kombu)
Japanese dried kelp (kombu)

By the seventh century AD, a sort of dashi using kombu and katsuobushi had developed. This was refined further and has become Japan’s most indispensable cooking stock, generally used in two forms – ichiban (primary) dashi and niban (secondary) dashi. Despite its hidden role, dashi could be said to be the heart of Japanese cuisine, not because of the prominence of its own flavour but because of the way it enhances and harmonises the flavours of other ingredients. The secret of Japanese cuisine is the art of enhancing and harmonising.

Umami world map
Umami world map

We’ve already heard about how kombu dashi was the raw ingredient responsible for Professor Kikunae Ikeda discovering and naming Umami as the fifth taste in 1908. In 1913 and 1957, there followed the discovery of inosinate and guanylate, respectively, as sources of Umami. Since the 1980s, further research has led to a wide international acceptance of Umami as the fifth taste. The ingredients of dashi are all rich in the substances that are the source of Umami. Kombu has the highest natural levels of glutamate of any foodstuff in the world. Katsuobushi and niboshi contain high levels of inosinate and dried shiitake mushrooms of guanylate. The benefits of Umami are multiple. Aside from being the fifth basic taste, it also has a synergistic effect. When glutamate and other sources of Umami are combined, the Umami taste is boosted, producing a result greater than the sum of the ingredients. Umami also serves to enhance other tastes, bringing a satisfying fullness and freshness to the food it permeates.

Tomatoes and the Western World

Of course, just like the other four primary tastes, Umami is by no means exclusive to Japanese or Asian cooking and ingredients. Two of the most Umami-rich ingredients can actually be found in Italian staples: tomatoes and parmesan.

Tomatoes

First, we come to tomatoes. “Of the many plant foods that provide Umami in western tradition, the tomato is foremost,” according to the Umami Information Center. Its attractive, full, rounded ‘meaty’ flavour comes from its heavy load of glutamates, and this flavour is reinforced by its unique crimson colour, the colour of blood which is the very essence of animal life. The Umami theme remains constant, though the way it is expressed varies from culture to culture. Beginning in Asia with fermented soybeans, migrating through England with walnuts and mushrooms and emerging triumphant with tomatoes in American ketchup, evidence of a deep-rooted worldwide inclination to exploit glutamate-rich foods for savoury seasonings and condiments is clear.

Tomatoes contain high levels of the Umami provider glutamic acid, and as the fruit ripens these levels increase. However, most of the Umami is found within the seeds, which poses a problem for the many Italian and Mediterranean recipes which call for these to be removed.

Heston Blumenthal, owner and chef at the triple Michelin starred Fat Duck restaurant in the UK, began to question this practice of removing the seeds, and wrote an academic paper on the subject in conjunction with scientists at the food sciences faculty of Reading University in the UK. In a nutshell, their findings were that the inner part of the tomato had a stronger Umami aftertaste than the outer part. As such, these are essential in sauces and pastes if you really want to get that Umami flavour.

Parmigiano Reggiano

Next we come to Parmigiano Reggiano, the DOP cheese from Emilia Romagna, which blows other cheeses out of the water in terms of glutamate levels. According to the Umami Information Center, its levels are almost on a par with kombu, the kelp used to make dashi.

Parmigiano Reggiano
Parmigiano Reggiano

The cheese is aged for two to three years, producing a rind browned like burnt sugar. Amino acid crystals form in the body of the cheese and create a gritty texture. An incredibly high 1.6% of Parmigiano-Reggiano is pure glutamate, the free amino acid which produces the Umami taste. Hard cheeses with a balanced taste between Umami and saltiness are widely used in powdered or grated forms as a seasoning in cooking.  Flaked, ground, or powdered, it is an essential ingredient in many dishes.

Green Tea

Finally, of course, Umami doesn’t have to be limited to the world of food. Good quality green tea has very high levels of Umami, and can for many people be their first reference point for the fifth taste. The sweet and Umami sensations are said to result from the presence of theanine and glutamate, both types of amino acid, the astringent taste from catechin, and the bitter taste from caffeine. To read more about one green tea grower who is pioneering a tea plantation in Portugal, head to our interview with Nina Gruntkowski of Chá Camélia.

Green tea

This article has been written in collaboration with Umami Information Center. In 1982, in order to disseminate information about Umami globally, the UIC was founded with the support of The Umami Manufacturers Association of Japan.

Special Thanks to Dr. Kumiko Ninomiya.

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