The very idea that a primary taste remained so elusive to the palate that it took until 1908 to "discover" it - and a further 80 years for an international scientific symposium to officially declare it as such - is strange.
For millennia, the so-called "fifth taste" lurked, ineffable, amongst the other more identifiable primary tastes of sweet, sour, salty and bitter, just beyond reach of the rational mind to grasp it. It took a Japanese professor of chemistry at Tokyo Imperial University to identify it.
Kikunae Ikeda concerned himself with the particular taste of Japanese ‘dashi’ broth that didn’t seem to be accounted for by the other, more recognisable tastes. He wanted to know how the relatively bland tofu his wife gave him for dinner was made to taste so much better by the simple addition of dashi.
He realised that the flavour came from kombu (kelp), which was one of the ingredients the Japanese had been using to make dashi for thousands of years. He called it umami. It’s a Japanese name for a quintessentially Japanese concept.
Formed from a synthesis of two words meaning “delicious” and “taste”, umami is a taste in its own right, but its true worth is in the way it enhances the flavours of the food it is added to.
It has a synergistic effect: when two sources of umami are combined, the umami taste is boosted, producing a result greater than the sum of the ingredients.
In this respect, umami defies rational explanation. How can something that on its own is almost tasteless, work such magic on the ingredients it is added to?
These are concepts hard for the Western mind to fathom, but come naturally to the Japanese, influenced as they are by successive imports from China of Taoism, Confucianism and Buddhism. Umami is the Zen of taste.
Even attempts to translate the word umami into Western languages (usually as “savouriness” or “deliciousness”) somehow fal short. Ikeda found that it was glutamate, an amino acid, found in the kombu that was responsible for umami.
A few years after Ikeda’s discovery, the other main constituent of dashi, "katsuobushi" bonito flakes, was found to contribute to the umami taste in the form of inosinate.
Dashi, the purveyor of umami to nearly all of Japanese cuisine - the ingredient that makes food taste incontrovertibly Japanese - is made quite differently to the way broth is made in the West.
Rather than boiling ingredients such as meat or fish bones and vegetables over a long period of time to release flavour, dashi is made by steeping a select number of carefully prepared ingredients in water for short periods of time.
It is a very simple process: dried konbu is soaked in water to which are then added flakes of katsuobushi. The water is then strained to produce the fragrant dashi.
It’s an almost tasteless liquid, but added to other ingredients, it works magic.
Quintessentially Japanese it may be, but umami has been found to exist in other foods around the world. Parmesan, cooked tomatoes (and therefore ketchup), marmite, sauerkraut are all examples.
The ancient Romans created savoury condiments called liquamen and garum from fermented fish that were undoubtedly high in umami.
«When you choose a classic Western combination like Parmesan and tomato, in part what you’re choosing is the taste of umami, although you might not realise it,» says Heston Blumenthal of the Michelin-starred The Fat Duck. «Despite this, umami is still something that, in the West, we’ve never really heard of.»
Blumenthal likes to use Japanese ingredients to get what he calls the umami “hit” at The Fat Duck. «I like to pulverize kombu, which can make a difference to the overall flavour of the dish without itself being detected as an individual ingredient.»
It has been shown that the presence of umami precludes the need for salt, and that it engenders a sense of fullness and wellbeing that may help in the fight against obesity.
Science has given a number of answers as to why this is so: it is not only on the tongue but also in the stomach that we have receptors sensitive to umami. The gastric vagal nerve in the stomach reacts solely to glutamate, and sends signals to the brain to start the process of digestion.
It is the amino acids – the essential building blocks for complex proteins – that we taste in umami. It should come as no surprise, then, to learn that our first taste of umami is from breast milk.
It is another facet of Japanese culture to render the exquisite profane, as the many Coca-Cola soft drink dispensers in some of Japan’s mocst sacred and beautiful spots testify. Just as Ikeda succeeding in identifying one of the most magical elements of Japanese cuisine, he then proceeded to synthetically produce it.
In 1909, the Ajinomoto company was formed to begin mass-producing artificial "umami" in the form of the much-maligned Monosodium Glutamate (MSG). One part of Ikeda’s legacy is to have developed a way of adding artificial flavour to tasteless fast food such as the potato crisp. But it is also to have discovered the elixir of great food.
For those who'd like to deepen their Umami knowledges, a book tells the story of the fifth taste, and much more. The hungrier ones can decide between an entire selection of Umami meals : there are Umami burgers, refined sake pairings at Nobu, or even fifth taste dinners on a plane.