Value Village ／ Food & living
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Dashi — the light stock behind miso soup, noodle broth and much else — is the foundation of Japanese cooking. Yet a great deal of received wisdom about it is wrong. Once you understand the mechanism, you see why the two main ingredients are combined.
Glutamate from kombu (昆布, dried kelp) and inosinate from katsuobushi (かつお節, dried, smoked bonito flakes — a fish product). Combine the two and the umami is perceived not as a sum but as 7–8 times as strong as either alone. This is known as the "umami synergy effect," and ichiban dashi (一番だし, "first dashi") makes use of it.
[Verify] The "7–8 times" figure is based on material from the Umami Information Center and others. Confirm against primary sources before publication.
Kombu kept at a rolling boil is generally described as releasing slime and off-flavours, and katsuobushi simmered for long loses its aroma. Each ingredient is handled differently. "Simmer for a long time" suits neither.
There is also a method that simply steeps kombu in water (mizudashi, 水出し — cold brewing). It may take time, but that is not the same as taking effort.
You can make dashi from one ingredient, but the synergy arises only when the two are combined. There is a rational reason for combining them.
Commercial dashi (the granules, sachets and concentrates sold in every supermarket) has its uses. What matters is knowing what you are using and choosing accordingly. Umami seasoning (うま味調味料, MSG) draws on the same glutamate.
Ways of cooking with the spent ingredients (dashigara, だしがら) have been passed down in households across Japan. They are also known as a way of reducing food waste.
Umami drawn from ingredients can be used beyond Japanese cooking. The umami synergy effect has no nationality.
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https://www.umamiinfo.jp/what/tasting/make-use.html
https://www.umamikyo.gr.jp/knowledge/katsuyou/experience_02.html
https://www.maff.go.jp/j/keikaku/syokubunka/k_ryouri/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Some ingredients need thorough cooking. Eat raw only foods that are sold for raw consumption. If you have allergies, check the ingredients.
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