The more recognizable artistry of Japanese knife making was formed in the city of Sakai, just south of Osaka, in the 14th century. This was when the city became the seat of samurai sword production, which was recognized with a distinct seal of approval by the Tokugawa Shogunate in the 16th century. By the 19th century, as part of the Meiji Restoration, the shogunate lost its powers and the government banned carrying swords as part of an attempt to “modernize” Japan. So the swordsmiths began applying their skills exclusively to culinary tools.
The process of crafting Japanese knives today largely follows the tradition of creating katana swords, the legendary curved blade of battle. Metalsmiths use the finest tamahagane steel to make a katana, valued for both its labor-intensive creation and for its duality. A katana is made up of both high-carbon and low-carbon tamahagane. The former allows for a razor-sharp edge and the latter allows for shock absorption, which made the katana exemplary on the battlefield.
The best pieces of tamahagane are sent to a swordsmith to remove any impurities. Once this process is complete, the two types of tamahagane are forged together. Before firing the katana for a final time, a thick mixture of clay and charcoal powder is painted onto the upper side and back edge of the sword. This top layer serves to protect the blade and results in the recognizable wavy design called the hamon. After the firing, the knife must be “quenched” in water. During this cooling process, as the two types of tamahagane contract differently and at separate rates, the sword bends ever so slightly. Now fully forged, the katana is polished — a step that can take over two weeks.
“The hand-forging methods and artistry are mainstays.”
Today, Japanese knives have evolved from a weapon to a culinary instrument, but the hand-forging methods and artistry are mainstays. Unlike the double-bevel blade of the western-style knife, the traditional Japanese-style knife has a single bevel, which produces thinner, more precise cuts. The yanagi, a long and thin knife, is the primary instrument of Japanese sushi chefs. Its length and sharpness allows for a clean cut through raw fish, creating smooth, flawless slices. Intended for gutting and filleting fish, the deba has a thick and sturdy blade to pass through the bones, heads and ribs of fish. A Japanese boning knife, the honesuki is a more heavy-duty tool meant for meat and poultry. The usuba, with its particularly slender edge, is used for cutting vegetables.
The next time you see one of these knives, take a moment to really look at its impeccable finish and delicate edge. Feel its balanced counter-weight in your hand. It’s been said that the samurai’s sword is his soul. In the same spirit, Japanese chefs today are merited on their intricate knife work — a true credit to centuries-old craftsmanship.