What is Dashi? What is Dashi?

Dashi and
Umami –
The Essence of
Japanese Cuisine

Although Japanese cuisine is rich in diversity and visually attractive, there is one element underlying its appeal that is not apparent to the eye. This is a deceptively simple element called “dashi,” the stock that forms the basis of, and invisibly permeates much of, Japanese cuisine.

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’ flavor.

Dashi most commonly utilizes 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). 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 flavor other dishes.

By the seventh century, a 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 flavor but because of the way it enhances and harmonizes the flavors of other ingredients. The secret of Japanese cuisine is the art of enhancing and harmonizing.

Umami – The Key
to Dashi’s Taste

A single word holds the key to the magic of dashi – umami. In 1908, Prof. Kikunae Ikeda of Tokyo Imperial University discovered a taste in kombu dashi not accounted for by any combination of the basic tastes of sweet, salty, bitter, and sour. He identified the source of this taste as glutamate. The taste itself he dubbed, “umami.”

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 two 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.

What is Umami?

Umami is the fifth taste, joining 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. 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 good or not is a comprehensive yet subjective evaluation determined by elements such as taste, aroma, texture and temperature, besides other factors such as appearance, color and shape, as well as one’s 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.

What is Umami

Dashi Ingredients

The Japanese stock known as dashi is an indispensable part of Japanese cuisine. Made using a number of very special ingredients, it serves to transform the flavor of any number of dishes. the subtle flavor of most types of dashi might not be easily identified in a dish; what dashi does, however, is to accentuate and draw out the flavor of other savory ingredients in the dish, resulting in an increased depth, intensity, and complexity in flavor. How the dashi achieves this is intrinsically linked to umami, the fifth basic taste alongside sweet, sour, salty, and bitter.

Dashi Ingredients – Kombu (Kelp)

Kombu, which grows in abundance off the northern island of Japan, Hokkaido, is harvested and dried before use. It can also be used on its own to make vegetarian dashi. The choicest kombu (kelp) used to be shipped with great care from far off Hokkaido to Kyoto, the ancient capital of Japan that flourished for nearly a thousand years. In the Heian Period (794–1185), shojin ryori, a type of vegetarian cooking, was introduced along with the teachings of Buddhism that warned against the taking of life. The ingredients used in shojin ryori consist entirely of vegetables and soybean products – meat, fish, or seafood are never used. Kombu dashi (kelp stock) is indispensable for enhancing the taste of the vegetables used in shojin ryori.

Umami rich

Dashi Ingredients – Katsuobushi

Katsuobushi is made of bonito or skipjack tyna, a sea fish that appears in Japanese cuisine in a number of guises. The fish is dried and then impregnated with a beneficial mold that induces fermentation, leading to a deeper, richer flavor. The process takes several months and results in a surprisingly hard, yet flavorsome, foodstuff. Once the blocks are ready, they are shaved, using a special plane, for use in cooking. Other fish such as tuna, mackerel, and sardine can also be used in this way.

Umami rich

Dashi Ingredients – Dried Shiitake

Another ingredient common in vegetarian dashi is Japan’s best-known indigenous mushroom, the shiitake. It is sun-dried to intensify the taste before being soaked in water to create a delicious stock that complies with the strict rules of shojin (Buddhist vegetarian) cuisine.

Umami rich
Dried Shiitake

Dashi Ingredients – Niboshi

The other main ingredient used in dashi is niboshi, a term that covers a number of different types of small, dried fish, such as anchovy and pilchard. They are traditionally sun-dried and then cooked in water to create the stock, which has a strong taste with a slightly bitter edge, and is suited to robust dishes, such as miso soup and hotpots.

Umami rich

Primary Dashi –
Ichiban Dashi

Ichiban Dashi

Classic dashi is made using kelp and katsuobushi (dried bonito flakes). A range of stocks of different character can be created from just these two ingredients. The most prized is ichiban (primary) dashi, which is made by soaking or gently heating the finest kombu and briefly adding katsuobushi. It is used in dishes, such as clear soups, where the aroma and quality of the stock is of utmost importance. Meanwhile, niban (secondary) dashi is made by reusing the ingredients from ichiban dashi to create a less refined but more versatile stock.


  • 3 L soft water
    100 ml water
    20 g ma kombu
    80 g dried bonito flakes
    (bonito honkarebushi, chiai removed)

  • Ma Kombu
    Ma kombu gives a delicate color and premium quality sweetness to dashi.
    It is relatively clearer than other kinds.

  • Bonito Honkarebushi, Chiai Removed Thin flakes of dried bonito are used; the chiai part of the fish is not included. These are used chiefly to heighten the aroma of the dashi.

Preparation method

  • Place the kombu in a pan with the water and leave to soak. Allow about 1.5 hours in winter and 20–30 min in summer. If using a large pan, go straight to step (2), as the kombu will have enough time to soak as the water heats.

  • Heat until just before it reaches boiling point. Aim to take it out at the point at which small bubbles appear in the pan. If the kombu is left too long, it will spoil and thus taint the dashi.

  • Pour 100 ml water to ensure that the temperature is just below 100°C.

  • Turn off the heat and immediately add the bonito flakes. When the flakes sink to the bottom of the pan, remove the scum that has risen to the surface.

  • Immediately strain the dashi using a cotton cloth.

  • The ichiban dashi is ready to use.

More about Japanese Dashi

  • Kombu Dashi

    Kombu dashi is a dashi taken from the kombu, plant. The kombu is cultivated in Hokkaido and a part of Tohoku Japan.

  • Ichiban Dashi

    Ichiban dashi (first brewed dashi) is based on kombu dashi to which katsuobushi is added. In addition to the glutamate and aspartate of kombu, umami from katsuobushi; glutamate and nucleotide inosinate are added. With the aroma and flavor of katsuobushi, it has strong umami. Some ryotei, Japanese high-end restaurants, use tuna bushi instead of katsuobushi.

  • Niban Dashi

    A common way to make niban dashi (second brewed dashi) is to add half as much of the water used in ichiban dashi onto kombu and the katsuobushi used in ichiban dashi, then cook it slowly. It brings stable umami and goes well with simmered dishes and miso soup.

  • Niboshi Dashi

    Compared with katsuobushi, niboshi dashi has a slightly more fishy taste. It can be used for dried food and pungent ingredients and miso soup.

  • Shojin Dashi

    To prepare dashi for shojin, vegetarian dishes, kombu is mainly used. Fish and meat are not allowed to be used in Buddhism, so katsuobushi and animal bone cannot be used. Besides kombu, dried shiitake mushroom, soy beans, dried gourd, or vegetable skin is used. Dried shiitake mushroom has a stronger umami and aroma out of these; however, its strong character unbalances the taste. So please be careful about how much you use.

Umami Synergistic Effect in Dashi

Umami substance in Kombu dashi and ichiban dashi from a luxurious traditional ryotei restaurant in Kyoto. The umami substance found in kombu dashi is glutamate alone, one of the amino acids, whereas in ichiban dashi, approximately the same amount of the glutamate and inosinate was found.

Kombu dashi contains umami of glutamate, a kind of amino acid. In ichiban dashi, the synergistic effect that occurs from glutamate and inosinate of nucleotide makes us taste umami 8 times more than the quantity of the real umami substance. A research study reported that umami synergy becomes the strongest when the amounts of glutamate and inosinate are almost the same. So, the recipe of ichiban dashi served at restaurants in Kyoto can be said to be very reasonable.

Healthy Japanese cuisine in the
global spotlight

Recent years have seen a growing shift in the developed world toward fewer calories and animal fats, as people aimed to prevent lifestyle diseases and maintain good health. As part of this dietary trend, Japanese cuisine has enjoyed burgeoning popularity, thanks to its health properties. Rather than relying on animal fats, Japanese cooking uses the umami of dashi to highlight the intrinsic flavors of ingredients, and chefs from all over the world have started visiting Japan to study these cooking techniques.

In learning how to make Japanese dashi, they master the use of umami as an alternative to animal fats before going on to develop their own approaches to umami-oriented cooking. For instance, a kaiseki-style bento box made by one traditional Japanese restaurant uses over 40 different ingredients yet contains fewer than 500 calories. The secret is the Japanese cooking technique of using the umami of dashi to enhance flavors.

Umami in Washoku