Katsuo-bushi (dried skipjack tune) is the taste-clincher
behind Japanese food.
Of course, there are other things that can be used for a stock base,
but among Japanese stocks, katsuo-bushi is the most commonly used.
Katsuo-bushi is the Flavor of Japan.
Used as the stock for miso soup, soba noodle and tempura dip, or for
Japanese style boiled vegetables, katsuo-bushi is essential to Japanese cuisine
for its ability to greatly enhance flavor.
Katsuo-bushi is a very familiar item to Japanese.
Until recently, most families had their own Katsuo-bushi plane
(used to shave flakes off the dried tuna).
Today, however, fewer families shave their own katsuo bushi for immediate use.
This is because vacuum-sealed packs of machine shaved katso-bushi are readily available.
The Making of Katsuo-bushi
Katsuo-bushi is made by smoking skipjack tuna repeatedly.
Before a freshly caught skipjack tuna becomes katso-bushi, undergoes the following process.
1. First, the guts and head of the freshly caught skipjack tuna are removed,
the fish split open and bones carefully removed.
2. The fish are then boiled for roughly one hour with skin intact.
3. After this, the fish are smoked for 8-9 hours a day.
The fish are usually smoked for 10 or 15 times.
At this point, the katsuo-bushi is done, though some put a type of mold
(Eurotium herbariorum) on the fish then dry it in the sun.
It is said that the mold works to remove the smell of smoke and
fishiness from the katsuo-bushi.
The most important component in Katsuo-bushi is inosinic acid,
water soluble Uma-mi component. The mold absorbed the inside water of katsuo-bushi
to the surface, which enhance the drying condition.
It is said that katsuo-bushi is the hardest food.