Katsuobushi (鰹節) is a basic ingredient in the Japanese kitchen made from Skipjack Tuna which has been steamed, dried, smoked and then cured using Aspergillus glaucus, a type of mold. This process turns the fish into a wood-like block and significantly increases the amount of inosine monophosphate (IMP) contained within the fish. The Katsuobushi is then shaved on a plane before being used for cooking.
What's it taste like?
Since it's dried and shaved very thin, it has an almost paper-like consistency, but as it meets your tongue, it explodes with an intense smoky flavor that almost tastes like you're sucking on a bouillon cube, or a piece of dry-cured ham without much salt. The flavor is more meaty and smoky than fishy, and if you've ever had miso soup before, you'll recognize the flavor, since miso soup is made using dashi stock extracted from katsuobushi.
Where do I get it?
Katsuobushi should be available at any Japanese grocery store and may be found in the "Asian" section at major supermarkets. It can also be purchased online at Amazon, and many other specialty websites, like Kokoro Care Packages. They either come in big plastic bags, or in smaller bags which contain small serving sized packets.
When is it best?
Since it's a dried food, there is no season, however you want to make sure it's not past its expiration date as the flavor diminishes as it gets older.
How do I use it?
Katsuobushi comes in a few different thicknesses. The thick ones are used for making dashi (Japanese stock), while the thinner ones can be used as a topping for various dishes including okonomiyaki and oshitashi. When mixed with soy sauce, it's called okaka and is a common filling in onigiri (rice balls).
Some studies have shown that when katsuobushi interacts with certain enzymes an oligopeptide is produced that lowers blood pressure.
kezuribushi, kezurikatsuo, hanakatsuo, shaved skipjack, shaved bonito, bonito flakes, skipjack flakes