What is dashi ?

Dashi is the quintessential stock in Japanese cuisine and forms the basis of a huge variety of dishes. It is made using a few specific ingredients and, although it appears extremely simple and straightforward, the effect it has on the flavour of a dish is profound. It is made by boiling and soaking, generally for a short period of time, certain animal and vegetable products that enhance the flavour of a dish. These are principally konbu, or kelp sea vegetable, katsuobushi, or dried bonito fish shavings, niboshi, or small dried fish such as sardines and shiitake mushrooms.Dashi has a long history in Japanese cuisine. It is known that boiling was first used as a cooking method in Japan in the Jomon period (c. 10,000-3,000 BC), when broth obtained from boiling seafood and fishbones was used to flavour other dishes and by the seventh century AD konbu and katsuobushi were being used as they still are today. The process was refined over the years and dashi really came into its own during the Edo period (1603-1867), when many of today’s most popular Japanese dishes came into being. Today, dashi is used in a wide variety of dishes including nabe hot pots, suimono clear soups, tempura dipping sauce and of course the ubiquitous miso soup to name but a few, and it enhances the flavour of a wide array of cuisine.
Dashi type
Characteristics and usage
Katsuobushi+Konbu
Ichiban dashi
This is a highly aromatic, clear dashi with a refined taste. It is best suited to dishes where delicate flavours are required, such as suimono (clear soups), chawanmushi (savoury egg custard) and steamed vegetables.
Niban dashi
An intensely flavoured dashi that is made using the konbu and katsuobushi left over from ichiban dashi. It is best suited to robust dishes such as nabe (hotpots), miso soups and nimono (simmered dishes).
Konbu
Soaked
A sophisticated dashi with a strong umami taste. The soaking method ensures that the sliminess or imperfections of the konbu are not apparent and is therefore suitable for soups and simmered dishes in Buddhist shojin cuisine.
Boiled
This dashi has plenty of umami from the konbu, and is aromatic with a deep taste. It is suitable for use in dishes such as nimono in shojin cuisine and can be made quickly.
Niboshi
This dashi is usually used in miso soups and nimomo, but if made with quality niboshi it can also be used in suimono (clear soups).
Shiitake
Used in shojin cuisine and dishes where the flavour of the ingredients must be drawn out, such as nimono, tsuyu dipping sauce for noodles and takikomi gohan, where rice is steamed with other ingredients and flavourings.It’s stock, but not as we know it The key difference between dashi and other types of stock around the world such as the bouillon used in Western cuisine and the Chinese stock known as tang is that where in the latter case relatively simple ingredients such as chicken are boiled over a long period of time to release flavour, when making dashi it is common to use ingredients that have been carefully prepared and matured over a long period of time, for example katsuobushi that take six months to prepare and konbu that is not used until it has grown for two years to fully mature, and for them to then only be soaked in water or heated briefly. This ensures that only the essence of flavour of each ingredient is drawn out. Importantly, the main flavour element present in all dashi ingredients is the savoury taste known as umami, which is considered to be the fifth basic taste besides sweet, salty, sour and bitter. The most interesting aspect of umami is that as well as providing an appealing savoury taste of its own it draws out and enhances the taste of other ingredients in the dish. This contrasts with Western stock, whose taste is layered upon those of other ingredients. Dashi for different dishes The classic dashi is that made using konbu kelp and katsuobushi dried bonito flakes. The highest quality dashi , which has a delicate flavour that is ideal in clear soups such as suimono, is called ichiban dashi and is made using fresh konbu and katsuobushi. Niban dashi , which has a richer flavour, is made usingkonbu and katsuobushi that have been previously used to make ichiban dashi and is more suited to miso soup and other strongly flavoured dishes. The other main varieties are those made usingkonbu only and shiitake mushrooms, both of which are used in the Buddhist inspired, vegetarian shojin cuisine, as well as that made using niboshi , or small dried fish such as iwashi , which is a more robust dashi for inclusion in strongly flavoured dishes such as nabe hot pots.
How to make ichiban dashi
　Makes 3 cups　· 8g bonito flakes　· 4cm x 4cm piece dried konbu (kelp)　· 3 cups (600ml) water
Make a few slits in the konbu and place in a saucepan with the water over a medium heat.
Remove the kelp just before it boils and add the bonito flakes.
Bring to the boil and strain.
　
　
How to make niban dashi
　Makes 3 cups　· Recycled bonito flakes and konbu (kelp) from 　　ichiban dashi (see above)　· 5g bonito flakes 　 · cups (600ml) water
Place the reserved bonito flakes and konbu from the ichiban dashi and water in a saucepan.
Heat to just below boiling point, then simmer for 15 minutes. Add fresh bonito flakes.
Wait until added bonito flakes sink, remove from heat and strain.

Umami: the secret of dashi's success The word umami and the concept behind it are now becoming recognized and understood by professional chefs and food experts in the West, but the term was first coined in Japan as long ago as 1908 and it in fact describes a taste that has played an essential part in all cuisine all over the world since earliest times. The fifth taste of human beings The way in which human beings perceive food is a complex combination of a number of factors, which encapsulates not only the taste of the food but also its aroma, the atmosphere in which it is served and even the mood of the diner. As far as the actual taste of the food goes, however, it was generally held by scientists and taste experts to consist of four basic tastes, namely sweet, sour, salty and bitter, which served rather like primary colours and could be combined to build more complex tastes and flavours. In 1908, however, a Japanese scientist, Professor Kikunae Ikeda of Tokyo Imperial University, made a discovery that would come to have a great impact on the way taste is perceived. Having discerned a taste sensation in konbu dashi that could not be accounted for among the existing four tastes he carried out experiments that identified the source of the taste as glutamate. He christened the taste umami, the word for deliciousness in Japanese, but which in this case equates to savouriness. Subsequent research by other Japanese scientists identified other naturally occurring substances that also produce the umami taste sensation, namely inosinate, identified in 1913, and guanylate, identified in 1960. Further breakthroughs came in 1996 and 2002 when taste receptors were discovered on the human tongue that respond specifically to the umami taste. It was this breakthrough that led to umami being confirmed in the minds of many scientists as the fifth basic taste and led to it becoming more accepted in the wider culinary world. Umami-rich dashi ingredients The main substances that provide umami are glutamate, an amino acid, and 5’-inosinate and 5’-guanylate, which are classified as nucleotides. Amino acids are the building blocks of protein and are released when proteins are broken down through maturation, ripening and fermentation. For this reason glutamate levels tend to be highest in foods such as cured meats, cheese and ripe vegetables such as tomatoes as well as fermented seasonings such as Asian fish sauce and Japanese miso paste. Glutamate is also found in many kinds of meat and fish, but the foodstuff with the highest naturally occurring glutamate levels is in fact konbu, or kelp, the sea vegetable that is essential to dashi stock (See Figure 1-1). Of the other two umami substances, 5’-inosinate is found in animal substances such as meat, dried sardines and another key dashi ingredient, katsuobushi or dried bonito flakes (See Figure 1-2). 5’-guanylate, meanwhile, is found in smaller quantities in pork, beef and chicken, but is most abundant in varieties of mushroom, in particular dried shiitake mushroom, which is a popular ingredient in vegetarian dashi (See Figure 1-3).A beautiful synergism Another important aspect of the umami taste and the substances that provide it is the fact that when the various substances are combined together in food the perceived strength of the umami taste is substantially increased, more than the sum of the separate ingredients. This is known as the synergistic effect of umami and although the reason why it occurs is still not completely understood by scientists it has been exploited by Japanese chefs for centuries. As explained in Figure 2 below, the most quintessential example of the synergistic effect in action is that of ichiban dashi made using konbu and katsuobushi. As explained previously, konbu has the highest naturally occurring glutamate levels of any foodstuff, while katsuobushi are high in inosinate. Both of these substances have an umami taste when sampled on their own but when combined together the perceived umami taste is dramatically increased compared with that of the separate ingredients. The home of umami Every cuisine in the world has its share of umami-rich ingredients and condiments, such as tomato ketchup from the USA, nam pla fermented fish sauce from Thailand and Marmite yeast extract from the UK. It is arguable, however, that it is a particularly important part of Japanese cuisine, which would explain why it was first identified by a Japanese scientist in a Japanese dish. It is often said that one fundamental characteristic of Japanese cooking is a desire on the part of the chef to preserve, accentuate and bring out the true deliciousness of each ingredient.
　
Figure 1: Quantity of umami substances in various foodstuffs
1-1 Foods high in glutamate
1-2 Foods high in 5’-inosinate
1-3 Foods high in 5’-guanylate
(Source: Umami Information Cemter)
This graph visualizes the effect that combining two or more umami substances has on the taste of food. konbu dashi contains 0.023% glutamate, as shown in the bar on the left. Ichiban dashi, made using konbu and katsuobushi combined, includes 0.023% glutamate from the konbu, as well as 0.005% glutamate and 0.027% 5’-inosinate from the katsuobushi . This gives an overall umami substance content of around 0.05%, as shown in the middle bar. When the actual perceived umami taste of the ichiban dashi is theoretically estimated, however, it is equivalent to that of a dashi that contained around 0.91% glutamate. That concludes the first part of our investigation into Japan's dashi culture. Why not check back here soon for the second part of this special dashi feature, where we take a detailed look at the ingredients without which dashi would not be as we know it today.