Learn about katsuobushi (dried bonito fish flakes), one of the essential ingredients in Japanese cuisine, including dashi (Japanese soup stock). We’ll talk about the different types you can find, the health benefits, and how to use this unique seafood product in your cooking!
Katsuobushi (鰹節 or かつおぶし), also known as bonito flakes, are dried shavings of katsuo (skipjack tuna or bonito, 鰹). It is the secret ingredient in making flavorful dashi (Japanese soup stock) and that curiously looking garnish that dances atop okonomiyaki (Japanese savory pancake).
Beyond flavors, bonito flakes are also high in amino acids, making them a great staple to keep in the pantry. Let’s discover this superfood and how to incorporate it into many Japanese dishes today!
Table of Contents
What is Katsuobushi?
Katsuobushi are shavings of skipjack tuna or bonito, known as katsuo. It’s most commonly used with kombu (kelp) to make Japanese soup stock called dashi. Thanks to its high inosinate content (a chemical compound), the fish shavings are incredibly high in umami and ideal as a flavor enhancer.
Katsuobushi is made by boiling, dry-smoking, then introducing Aspergillus glaucus, a beneficial mold that triggers fermentation in the fish fillet. The finished product resembles hard, petrified wood through a months-long drying process.
Most people might have seen shaved bonito flakes on popular dishes like takoyaki or okonomiyaki, but they also make delicious and healthy additions to other dishes.
What Does Katsuobushi Taste Like
While it resembles wispy pieces of paper, it has an almost explosive, intense smoky flavor. The umami flavor is more meaty than fishy, and the aroma is smoky, almost like a mix of dried/smoked fish and bacon.
3 Types of Katsuobushi
A good mold (as opposed to a malignant mold) is used to make katsuobushi, and it will improve the taste, and the fishy smell will disappear. Depending on the number of times the katsuobushi is covered with mold, the name of the katsuobushi changes as follows:
1. Arabushi (荒節)
- Refers to katsuobushi that is not covered with mold and does not undergo fermentation.
- The most common and economical type of katsuobushi.
- It has a strong smoky aroma with a slightly acidic flavor.
- All-purpose for making soups, sauces, and dressings.
- The more dark meat, the stronger the flavor.
2. Karebushi (枯れ節)
- Refers to katsuobushi that repeats the drying and fermentation process twice.
- Lighter-colored shavings, with or without dark meat.
- Suitable for making flavorful and aromatic clear dashi.
- Darker shavings are suitable for miso soups, simmered dishes, and dressings.
3. Honkarebushi (本枯れ節)
- Refers to katsuobushi, which repeats the drying and fermentation process at least three times.
- Much more complex and elegant in flavor and expensive compared to karebushi.
Various Katsuobushi Shavings
1. Hanakatsuo (花鰹) or Usukezuri (薄削り)
- Katsuobushi, which has been thinly shaved like flower petals, is called Hanakatsuo (‘flower-bonito’). Hanakatsuo is only made by shaving mold-free katsuobushi—arabushi.
- Shaved to a thickness of 0.03 mm to 0.07 mm.
- Thin pale pink petals that resemble large wood shavings.
- Some contain dark meat.
- Sprinkle on Okonomiyaki, Takoyaki, Yakisoba, and Hiyayakko (Cold Tofu) as a garnish.
- Economical for making Dashi (Japanese soup stock).
- Most easily accessible katsuobushi outside of Japan.
2. Atsukezuri (厚削り)
- Shaved to a thickness of over 0.2 mm, thicker than hanakatsuo.
- More dark meat (a higher concentration of chi-ai).
- Suitable for making a rich and robust Dashi (Japanese soup stock) and making braised dishes.
3. Smaller Shavings
The following smaller shavings are suitable for garnishing salads and cold tofu.
- Itokezuri (糸削り): Thread-like shavings.
- Saihenkezuri (砕片削り): Tiny bits and pieces used for “katsuo pack.”
- Konakezuri (粉削り): Powdered katsuobushi.
How To Use Bonito Flakes (And Recipes)
We’ve talked about the essential use of bonito flakes in making dashi. (Here is my Bonito and Kombu Dashi Recipe.) Another delicious use is okaka rice seasoning, where you cook katsuobushi with soy sauce, sake, mirin, and sesame seeds. You can mix the okaka into the rice or use it as a filling for okaka onigiri rice balls.
Here are some popular recipes with bonito flakes:
- Okonomiyaki
- Takoyaki
- Spinach Ohitashi (Japanese Spinach Salad with Bonito Flakes)
- Teriyaki Tofu
- Chilled Tofu
- Homemade Ponzu Sauce
They also make a great topping that you can add to your noodles, tofu or salad dishes for a punch of flavor and a complete protein (yes to that!).
Where To Buy
You can find bags of katsuobushi flakes at most Asian/Japanese supermarkets. Depending on how frequently you plan to use it and the purpose, you can choose to buy a large bag or smaller packets.
You can purchase good-quality Hana Katsuo here (ships internationally) or on online retail sites like Amazon.
How To Pick The Best
The best quality katsuobushi has light pink or beige shavings that will be slightly shiny. Dull flakes mean poor storage and may have oxidized, so check the contents before buying.
Substitutions
No substitution gives the same umami and delicately smoky experience as katsuobushi. The taste of delicious dashi will not be the same without bonito flakes.
Read: The Definitive Guide to Umami and Japanese Cuisine.
If using katsuobushi as a garnish, you could use shredded nori, natural yeast, powdered mackerel, or different kinds of fish flakes as a similar umami-rich topping.
How To Store Katsuobushi
Traditionally, you would shave a katsuobushi into thin flakes on demand while cooking. It’s shaved using a tool called katsuobushi kezuriki (鰹節削り器), similar to a wood plane. However, you can choose the shortcut and buy good quality shaved katsuobushi without shaving it yourself.
Katsuobushi is extremely sensitive to humidity, so properly store opened bags; otherwise, they will oxidize, making the color dull. To keep your katsuobushi fresh for longer, expel air from the bag, reseal, and store in a cool, dry, dark location. If the packages did not come in a resealable bag, immediately transfer them to an airtight container.
Store the bags in the freezer if you live in a humid environment.
Health Benefits
Katsuobushi contains all the essential amino acids necessary for the body because it cannot produce them on its own and thus must obtain them through your diet. Among its many benefits, amino acids are fundamental for creating collagen, which keeps your skin supple. It also contains vitamins and minerals, including iron, niacin, and B12.
Regular consumption of katsuobushi may help improve brain function, lower blood pressure, and boost metabolism. Also, it helps reduce the risk of several diseases, including dementia, heart disease, depression, and diabetes.
FAQs
Q: Why does katsuobushi move with heat?
Wondering why katsuobushi flakes move about on top of hot foods like okonomiyaki or takoyaki? Rest assured; the fish spirit isn’t resurrected. The shavings are so delicate and light that they seem to “dance” on top of hot foods.
Q: How long does katsuobushi last?
If kept in a cool and low-humidity environment with little exposure to air, katsuobushi should last for a few weeks. It’ll keep longer if the bag is unsealed, as it’s most likely pumped with nitrogen. Taste a few whisps and check the color to see if it’s good to go before use.
More Japanese Pantry and Superfoods to Explore
- Shiitake Mushrooms
- Kombu (Kelp Seaweed)
- Wakame Seaweed
- Top 5 Japanese Superfoods to Include in Your Diet
- Tofu: The Nutrient Rich Food
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