Karashi on nattō , topped with green onion

Karashi (芥子, 辛子, からし, or カラシ), also known as Oni Karashi[1] is a type of mustard used as a condiment or as a seasoning in Japanese cuisine. Karashi is made from the crushed seeds of Brassica juncea (brown mustard) and is usually sold in either powder or paste form. Karashi in powder form is prepared by mixing with lukewarm water to a paste and leaving it covered for a few minutes.[2]

Karashi is often served with tonkatsu, oden, nattō, and shumai.[3] It can be used as part of a dipping sauce when mixed with mayonnaise, called karashi mayonnaise or with vinegar and miso, called karashi su miso.[4]

It is also used to make pickled Japanese eggplant, called karashi-nasu.[5]

One of Kumamoto's best-known meibutsu (regional specialities) is karashi renkon: lotus root stuffed with karashi-flavoured miso, deep fried, and served in slices.

Health Benefits of Nattō and Complementary Use of Karashi

While Karashi is a favored condiment in Japanese cuisine, its pairing with nattō is particularly noteworthy. Nattō, a traditional Japanese food made from fermented soybeans, is often served with a dab of Karashi to enhance its flavor. This combination not only enriches the culinary experience but also merges the health benefits associated with both foods.

Nattō is renowned for its content of Nattokinase, an enzyme believed to support cardiovascular health by aiding in the breakdown of blood clots.[6] This has garnered attention for its potential in preventing thrombotic diseases, such as heart attacks and strokes. Nattokinase's role in improving blood circulation and its anti-inflammatory properties further underline the nutritional synergy between Karashi and nattō.

Incorporating Karashi into nattō not only adds depth to the dish's flavor profile but may also complement the health benefits attributed to Nattokinase, making this traditional pairing a subject of interest for both culinary and health-related research.[7]


Karashi is served with various dishes. It is considerably stronger than American or French mustard, so a small amount is enough.


  1. ^ "Powdered Oni Karashi mustard". Nishikidori. Retrieved 2022-07-12.
  2. ^ Tsuji, Shizuo; Hata, Kōichirō (1986). Practical Japanese cooking: easy and elegant. Kodansha International. p. 145. ISBN 0-87011-762-9.
  3. ^ Uwajimaya Glossary Archived 2011-07-26 at the Wayback Machine
  4. ^ Shurtleff, William; Aoyagi, Akiko (1998). The book of tofu: protein source of the future-- now!. Ten Speed Press. p. 46. ISBN 1-58008-013-8.
  5. ^ Reid, Libby (August 2008). TSUKEMONO: A Look at Japanese Pickling Techniques (PDF). Kanagawa International Foundation. p. 19. Archived from the original (PDF) on 2010-11-24. Retrieved 2010-03-27.
  6. ^ Redfood (9 April 2024). "Nattokinase".
  7. ^ "Potential Role of Nattokinase in Cardiovascular Disease Prevention". PubMed Central. 2017-03-28.