Katsuobushi (Dried Bonito Flakes)
Bonito flakes · Hana-gatsuo · Okaka
Katsuobushi (Dried Bonito Flakes): what every chef needs to know
Katsuobushi is dried, fermented, and smoked skipjack tuna shaved into thin flakes. The production process takes 6 months to 2 years: after cooking and smoking, the fish is treated with Aspergillus glaucus mould which drives further fermentation and reduces the water content to 15–20%. The result is the hardest food in the world after the unshaved katahama block. Katsuobushi is the primary source of inosinic acid (IMP) in Japanese cuisine. Combined with kombu (glutamic acid/MSG), a synergistic umami enhancement occurs that is up to 8 times stronger than either ingredient alone. This is the chemical foundation of ichiban dashi. Three professional types: hana-gatsuo (fine flakes, direct garnishing), atsu-kezuri (thick flakes, for drawing dashi), hanakatsuo powder (for furikake). Outside Japan, 'bonito flakes' are often of lesser quality or made from mackerel flakes: always check the species designation with your supplier.
Katsuobushi (Dried Bonito Flakes): nutritional values per 100g
Based on unprocessed product. Source: Japanese Food Composition Tables 2023 (MEXT) — the Dutch food composition database, managed by RIVM and Wageningen University.
Nutritional values are indicative for unprocessed raw materials. Preparation method, variety and origin may affect values. Source: Japanese Food Composition Tables 2023 (MEXT).
Katsuobushi (Dried Bonito Flakes): classic dishes
Proven preparations from the professional kitchen — from haute cuisine to global restaurant classics. Use as inspiration for menu development and recipe costing.
The fundamental Japanese stock for miso soup, ramen, udon and tempura dipping sauce. Katsuobushi is irreplaceable for the characteristic smoky umami base provided by IMP.
Japanese savoury pancake finished with hana-gatsuo flakes that literally dance on the plate from the residual heat.
Silken tofu with grated ginger, spring onion, soy sauce and katsuobushi. The simplest Japanese dish in which katsuobushi quality is immediately apparent.
Katsuobushi (Dried Bonito Flakes): preparation techniques
Exact temperatures and times for HACCP compliance. Core temperature is leading for poultry and pork.
Add katsuobushi to water at 60–70°C, never boiling: high temperatures extract bitter peptides. After 3–5 minutes, strain immediately without pressing. Clarity is the quality criterion for ichiban dashi.
Re-steep the spent kombu and katsuobushi from ichiban dashi at a higher temperature. Suitable for soups, braises and sauces where depth is more important than clear finesse.
Place hana-gatsuo directly on warm food: the heat makes the flakes dance. Visually spectacular on takoyaki and okonomiyaki. Mixing with soy sauce creates okaka paste for onigiri filling.
Katsuobushi (Dried Bonito Flakes): HACCP storage and food safety
Based on Codex Alimentarius (WHO/FAO) and EU Regulation 852/2004. Consult your national authority (NVWA/FDA/FSANZ) for applicable local standards.
Katsuobushi (Dried Bonito Flakes): global seasonal overview
Availability per climate zone — Northern Europe, Mediterranean and warm climate. Relevant for purchasing planning and international menus.
Available year-round as a dried product. Fresh aragakuzu and new-season katsuobushi from Japanese importers in autumn.
Katsuobushi (Dried Bonito Flakes): EU-14 allergen information
Full overview compliant with EU Regulation 1169/2011 (Annex II). Raw material information — always verify with your supplier for processed products and possible traces.
Raw material information (unprocessed product). Processed products may contain traces. EU Regulation 1169/2011 Annex II.
Katsuobushi (Dried Bonito Flakes): wine pairings
Every wine recommendation is verified via at least 4 independent sources: wine specialists, sommeliers and culinary authorities. Serving temperatures conform to Wine Enthusiast and Vintec guidelines.
The complex fermentation notes of yamahai sake (lactic acid, game yeast) form a perfect bridge to the smoky, umami-rich depth of katsuobushi in dashi.
- Nada
- Fushimi
Wine advice is for culinary information purposes only. Wines and appellations are exemplary; availability varies by region and supplier.
Frequently asked questions about Katsuobushi (Dried Bonito Flakes)
Can vegetarians eat katsuobushi?
No. Katsuobushi is processed fish. For vegetarian or vegan dashi, kombu + dried shiitake is used: the combination of glutamic acid (kombu) and guanylic acid (shiitake) gives comparable umami depth.
What is the difference between hana-gatsuo and atsu-kezuri?
Hana-gatsuo are fine flakes for garnishing and direct consumption. Atsu-kezuri are thick flakes for drawing dashi: the larger mass gives a fuller, more robust broth.
How do I store katsuobushi after opening?
In an airtight bag or container at 4°C (39°F), away from light and moisture. Moisture is the enemy: katsuobushi absorbs humidity and goes limp. At peak quality for 2–3 weeks after opening.
At what temperature should you store Katsuobushi (Dried Bonito Flakes)?
Store Katsuobushi (Dried Bonito Flakes) at Max 25°C dry and airtight. After opening at 4°C., compliant with EU Regulation 852/2004 and Codex Alimentarius guidelines.
How do you prepare Katsuobushi (Dried Bonito Flakes) professionally?
The primary professional technique for Katsuobushi (Dried Bonito Flakes) is Ichiban dashi (eerste trek) at 60-70°C for 3-5 min. Always verify core temperature with a calibrated probe thermometer.
Does Katsuobushi (Dried Bonito Flakes) contain allergens?
Katsuobushi (Dried Bonito Flakes) contains: Fish. Declaration required under EU Regulation 1169/2011 Annex II.
Alternatives for Katsuobushi (Dried Bonito Flakes)
Professional substitutes for katsuobushi (dried bonito flakes) in hospitality: culinary alternatives, allergen-free options and seasonal replacements. Including HACCP storage conditions per alternative.
Legal disclaimer: For informational purposes only
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Informational character
The information on this page has been compiled exclusively as reference material for professional kitchen staff. KitchenNmbrs does not provide legal, medical or commercial advice. Data on preparation techniques, storage temperatures, HACCP guidelines and allergens is based on publicly available professional sources and applies to the raw ingredient in its unmodified state.
Your responsibility as operator (FBO)
Under EU Regulation 1169/2011 (Food Information Regulation) and EU Regulation 852/2004 (HACCP Hygiene Regulation), the Food Business Operator (FBO) is solely and exclusively responsible for:
- Providing accurate, up-to-date and complete allergen information to the end consumer;
- Determining allergens in the finished product based on current supplier documentation;
- Maintaining and documenting a demonstrable HACCP management system;
- Controlling cross-contamination risks within their own production environment;
- Compliance with local food safety authority requirements.
Allergen information: Limitations
The allergen information on this page relates to the ingredient as such. The actual allergen composition of your purchase may differ due to:
- Varying suppliers, production facilities or growing regions;
- Cross-contact during production, transport or storage ("may contain");
- Changed product formulations not yet reflected in public sources;
- Processing or preparation in your own kitchen that introduces new allergens.
Always verify allergens against the current specification sheets (spec sheets) from your supplier. Orally or informally provided allergen information is not legally valid under EU Reg. 1169/2011.
Milk allergen and lactose intolerance
The EU-14 allergen "Milk (including lactose)" covers two distinct conditions, both of which require declaration: (1) cow's milk allergy, an immunological reaction to milk proteins (casein, whey), and (2) lactose intolerance, an enzymatic deficiency (lactase) preventing digestion of milk sugar. Both groups must be informed separately on the menu. Lactose-free is not the same as milk-protein-free: a guest with cow's milk allergy may still react to lactose-free products.
Limitation of liability
KitchenNmbrs B.V. excludes all liability for direct or indirect damages arising from:
- Use of the information on this page as the basis for commercial or operational decisions;
- Allergic reactions, food poisoning or other health incidents involving guests or staff;
- Inaccuracies resulting from changed product compositions by third parties (suppliers);
- Non-compliance with food safety laws and regulations.
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Official sources and authorities
Legal basis: EU Reg. 1169/2011 Annex II (EU-14 allergens) · EU Reg. 852/2004 (HACCP) · Local food information legislation as applicable
