Never flaking on flavour

A pillar of Japanese dining

It is hard to tangibly decide which of the sea-based foods in Japan is the most used. Last time we tackled one of the great titans of Japanese dining, seaweed. Well, one particular species of seaweed: Kombu.

Japan's Kombu-nience store

While Kombu does find itself tucked into countless Japanese dishes, it often travels via the Dashi detour. Also a key member of Dashi, today’s ingredient is a multi-meal-a-day player… making it a strong challenger for the extremely arbitrarily decided title of Japan’s most used sea-based food! With much hype, let me introduce Katsuobushi.

Katsuobushi on its own

Kellogg’s Tuna Flakes

While breakfast menus vary from person to person, corn flakes and milk could be seen as a traditional American morning meal. This choice is probably primarily based on the agricultural output of the country, with fields of cows and corn.

Japan is missing that cornucopia of maize and mazes of cattle. Instead, they make do with abundant fishing boats and rice planted wherever there isn’t a mountain (and even that doesn’t stop them sometimes). Thusly limited, a traditional breakfast here can comprise rice and fish. Yet, just like how corn doesn’t grow as flakes, Japanese fish often go through their own transformation.

Why not just eat raw fish with their breakfast?

Well, the entire concept of Katsuobushi harkens back to the days before refrigeration. Those were days when raw fish had to be served very closely to where the fish lived, lest it become an act of overt food poisoning. So, despite the many ancient and existing cities that perch on the coast, fish has not been a crop that naturally lends itself to storage. These people still wanted to be able to eat even on days when they didn’t catch anything, so for centuries there were incremental longer term solutions for fishing beyond “eat everything we catch before it goes off”.

So this brings us to salt-drying. Well done for working out the process! Originally this was purely a solar technology; any fish that wasn’t for today was salted and left out in the sun. The fish used in this process has also been identified in archaeological finds, typically a type of tuna also known as bonito or skipjack tuna.

Over time, drying in the shade became common practice for bigger fish like tuna. While this took longer than salty sun drying and was a tedious and thankless task, eventually the fish would harden to a wooden consistency. Katsuo, or hard fish, became the perfect chewing material for samurai.

This tuna jerky was popular but was not the easiest carrying snack as it was literally a hard brick of fish. An evolution finally occurred in the year 1674 with the introduction of smoke. While fire and smoke existed before then, the innovation of using it to dry the skipjack tuna meant that now they were cookin’!

Thank you for smoking

This deviation from salt preservation to smoking marks the true start of the bonito flakes we know and love. While Mr Dried Salt Fish still exists in Japan (as Shio Katsuo), the skipjack tuna is now known for its work through the medium of smoking.

This ingenious new method was such a big deal that we even know the name and story of the inventor, Kadoya Jintaro. The story goes that Jintaro the fisherman was shipwrecked away from his home prefecture, in Tosa (now in Kochi Prefecture). He decides to cook what remains of his catch, and in doing so realises that smoking actually dries out the water and improves the flavour! Now arabushi (smoked bonito) has been introduced to the planet.

Tosa soon becomes known for this new method and quickly acts to make it a regional trade secret. As a nationally prized export, the prefecture’s merchants became wealthy from the seafood peddling trade. With the rest of Japan desperate to get their hands on fish from Flavourtown Japan (Tosa), merchants were carrying more and more arabushi, and taking less and less care in storage.

This slow decline in quality control rears its ugly head only a century later from the invention. Accounts differ, but the common narrative is that carelessly packaged arabushi from Tosa was being shipped in wooden crates. One merchant, who remains nameless, discovers that his arabushi is mouldy. No worries! He decides that he doesn’t want to lose this cargo and just tries eating it. Somehow, this act of self harm works in his favour, as the mould has not poisoned him. Instead, it is actually another in a series of happy accidents that have made the arabushi even tastier.

Not content with cheating death, a method of intentionally growing fungi soon developed for the arabushi, finally leading us to the katsuobushi bonito flakes we love today.

Just one question.

Where’s the flakes?

So this process describes the tedious journey to getting to a Japanese breakfast, but still comes in fish-brick form. Since the accidental invention of katsuobushi, an even more elaborate system to create bonito flakes has developed. I’ll simplify it below, but each step could be expanded with details on the precise instruments and ingredients.

1. Catch (or receive) bonito

   Self explanatory, no fish means no flakes.

2. Cutting

   Having inspected for quality, make sure to gut, remove the spine, and divide the fish into four fillets, down the middle and by fin. Two from the dorsal front end, and two from the ventral.

3. Poaching

   The fish are back in the water. Just under boiling point for a bit over an hour, as an initial cook.

4. Deboning

   The smaller bones are meticulously removed by hand. So is a bit of the skin, since neither is wanted in the actual end product.

5. Smoking

   These Pisces pieces are smoked in a wood-fired oven for two to three weeks. Fancier places look at specific wood, as well as special chimneys at various times during the smoking process. Scrape off any skin or fat as well.

   If you’ve done this right, then you’ve already got arabushi at this stage! For Katsuobushi, there’s still a while to go. Hope this catch wasn’t meant for lunch.

6. Fermenting

   No longer a rogue merchant eating rotten food, this process is carefully calibrated. The smoked fillets are placed in a humid room with koji spores. These feed on fat, and they somehow create something that enhances the flavour. Do this for two or three weeks.

7. Drying

   If you thought the sun was done, think again! The fermented bonito is dried after about a week… then it’s time to repeat the fermenting process.

8. Repeating

   Do the fermenting drying cycle about 4 times. Your fish fillets should be getting very small now.

9. Shaving

   The fillets are about 1/5th the size when they come in. This means they’re rock hard and not suitable to chomp into. The shaving process then is much like wood shaving. These can be somewhat common household items, so if you were tired of the six-month process for making katsuobushi, now is a great time to exit. For the rest of you, let the shaving do the saving.

   

   Kezuriki

   Shaving katsuobushi the traditional way uses a wooden box called kezuriki. By holding the fish block in a hand, you can run it over the blade in a repeated motion and catching the petal-like shavings in the drawer below. Of course, if you’re mass-producing the katsuobushi flakes, there are giant metal shavers you can order too.

10. Eating

    Yes, finally this fish caught over half a year ago can be consumed! In fact, if you were an ingredient loyalist then you could enjoy katsuobushi for breakfast, lunch and dinner. Separate dishes of course. It has been six long months of preparation, you deserve to maximise this.

The Katsuobushi menu

Breakfast

Possibly the most pure/plainest form of dish, lovingly referred to as Neko Manma or cat food. This dish is simply katsuobushi on white rice. If feeling adventurous, add a raw egg to mix it in. If for some reason you didn’t make your own katsuobushi, consider paying a visit to Katsuo Shokudo in Tokyo’s Shibuya. They specialise in this breakfast, and only open until stock runs out.

Lunch

Assuming you want another flavour beside rice and shavings, then lunch can return you to one of Japan’s most popular easy eats. I won’t mythologise on okonomiyaki too much in this post as it deserves a full article. Simply put, this pan-fried delight excels at being a vehicle to consume more katsuobushi. Any joint worth its salt, gluten and oil will generously sprinkle the prized bonito flakes.

Dinner

Finally, katsuobushi is allowed to combine with kombu to make dashi. This all-use broth is featured in any number of dishes, from the base for miso soup or shabu shabu, to being used for oyakodon (chicken and egg rice). The list of Japanese food items that can use dashi is longer than this post. Take your pick and find one to include the katsuobushi in!

If all this sounds too tedious, you are able to find instant dashi. This gratifies the need of umami flavour, without the arduous multi month ordeal of making katsuobushi and then dashi.

So move aside tempura, furikake and panko. My prediction for the next crossover star from Japanese cuisine is katsuobushi. Versatile yet constantly fishy, you can be sure that the journey for your flakes has been worthwhile. In future editions, we’ll delve deeper into the many foods that this fish flake improves!