Hidden Fish Stock (Dashi) in Japanese Food
Miso soup, noodle broth and simmered dishes often use dashi made from bonito or dried sardines, even with no fish in sight. Which dishes to check, plant-based options, and how to ask.
Dashi is the base of Japanese cooking
Dashi is a broth that draws the umami out of ingredients into water. It is the foundation of a large number of Japanese dishes.
Japan's Ministry of Agriculture, Forestry and Fisheries (MAFF) explains that glutamic acid from kombu and inosinate from katsuobushi (bonito flakes) bring out dashi's umami when combined. Katsuobushi is mainly used as an ingredient for making dashi.
The Japan Tourism Agency's guide for restaurants also notes that Japanese cuisine often uses dashi. For vegetarian and vegan dishes, it advises avoiding animal-based dashi such as bonito and using dashi made from plant ingredients such as kombu instead.
Even when you can't see any meat or fish, the dashi may be made from fish. The Japan National Tourism Organization (JNTO) also warns that meat or bonito flakes can be hidden ingredients.
Types of dashi
| Dashi | Reading | Made from | Animal-based? |
|---|---|---|---|
| かつおだし | katsuo dashi | Bonito flakes (katsuobushi) | Fish |
| 煮干しだし | niboshi dashi | Niboshi (small fish, boiled and dried) | Fish |
| 昆布だし | kombu dashi | Kombu (kelp) | Plant-based |
| しいたけだし | shiitake dashi | Dried shiitake | Plant-based |
| 合わせだし | awase dashi | A combination, such as kombu and bonito | Depends on the mix |
If a menu just says "awase dashi" (mixed dashi), ask what is in it. Kombu with bonito is the classic pairing for umami.
Dishes that often use dashi
| Dish | Reading | How dashi is used |
|---|---|---|
| みそ汁 | miso shiru | Miso dissolved in dashi |
| うどん・そばのつゆ | udon / soba tsuyu | Dashi, soy sauce and mirin. MAFF gives a 12:1:1 guide ratio for noodle broth |
| 煮物 | nimono | Simmered in dashi, soy sauce and mirin, about 8:1:1 |
| おでん | oden | Listed as a dish simmered in broth at the noodle-broth ratio |
| だし巻き卵 | dashimaki tamago | Rolled omelet with dashi mixed into the egg |
| 天丼のたれ | tendon sauce | The Japan Tourism Agency's example uses seafood dashi in the sauce |
| 納豆のたれ | natto sauce | JNTO notes that the sauce packed with natto is often dashi |
A dish with only vegetables can still have dashi in its broth or sauce. Even if your miso soup only has tofu and wakame, ask about the dashi separately.
Switching to plant-based dashi
In its vegetarian and vegan menu examples, the Japan Tourism Agency shows how to replace "seafood dashi" with "kombu or mushroom dashi" in tendon sauce and miso-simmered udon. As substitutes for seafood it lists konnyaku and sea vegetables such as nori and kombu.
Temple cuisine (shojin ryori) is another option. JNTO describes it as food served mainly at Buddhist temples, tied to monks' practice of avoiding harm to living beings. It also notes that modern monks sometimes use dairy. Vegans should still ask about dairy and eggs, even at shojin ryori.
Beyond dashi, vegans should also check for eggs, dairy, honey and gelatin. The Japan Tourism Agency explains that vegans avoid these too.
How to ask
JNTO recommends being specific about what you can't eat: say no meat or seafood, and no animal products, including dashi and stocks. A card written in Japanese is easier to understand in a busy restaurant.
Restaurants that prepare broth and sauces in advance may not be able to change them for one order. This depends on the restaurant, so ask before you order.
For dishes made with bottled noodle broth or instant dashi, look for words like かつお (bonito), 煮干し (dried sardines) or 魚介エキス (seafood extract) in the ingredients.
Sources
Details can change. Please check with the restaurant before you go. If you have allergies or a medical condition, follow your doctor's advice. Religious rulings are left to certification bodies and to you.