Sushi knives: The secret to great sushi and cutting through walls

Legendary sushi chef and restaurateur Nobu Matsuhisa once told Travel + Leisure the secret to making great sushi boils down to “a sharp knife and a clean fish.”

It probably takes a little more than that, but Chef Nobu is not alone in prioritizing a good

blade.

Mitsuhiro Araki, the only sushi master to run restaurants with three Michelin stars in both Japan and Europe, told SCMP.com that his first major knife upgrade was like going from a modest sedan to a Ferrari.

“It was unbelievable, extremely fast. I had to learn how to control it,” he said of his blue carbon steel knife forged in 1966, the year he was born. “The knife edge is my tongue, my fingers and my mind, it becomes an extension of me."

He’s even granted the knife artistic license.

“If the customers touch the sashimi, they say it’s smooth, some slices are thicker, some thinner. The knife decides everything.”

There are several styles of knives used in sushi restaurants — the tall usuba is excellent for cleanly chopping vegetables without splitting them, and the thick deba makes quick work of dismantling whole fish — but the star of the show is the long and slender yanagiba, sometimes known as a sashimi knife. That’s the one you’ve likely seen a sushi chef working with.

The first thing that makes a traditional sushi knife unique is its "single bevel." Sushi knives are sharpened only on one side, while the other side remains flat. This allows the knives to be non-stick, and incredibly precise for shaping sushi without shredding or tearing it, which is key. Sushi chefs "pull" their knife back and through the fish, from the heel to the top of the blade, never, ever sawing.

Sushi knives are commonly made from high-carbon steel, rather than stainless. That means they rust easily, but are capable of being honed to a far sharper edge than stainless steel knives.

How sharp?

In February, burglars sliced through the walls of three businesses in El Paso, Texas using sushi knives. They broke into a sushi restaurant first and proceeded to use the chef's knives to cut through several walls and a large pipe in order to rob silver from a coin shop at the end of the strip plaza.

High-carbon steel knives that rust easily might take more care to maintain properly, but sushi chefs say they're worth it.

"Japanese chefs believe our soul goes into our knives once we start using them. You wouldn't put your soul in a dishwasher," goes the quote, attributed to the famed Masaharu Morimoto, best known as an Iron Chef from the TV cooking shows Iron Chef and Iron Chef America.

While the highest quality yanagiba knives can cost $500 to $1,000, the "world's most expensive sushi knife" is made by Yoshihiro Cutlery and features a hamon — a visible effect created on the blade by the hardening process — in the shape of Mount Fuji under a full moon. That one, "forged of the highest quality white steel according to the traditional methods used in ancient Japanese sword making" according to the company, will set you back $6,000.

If you're looking to get started at home though, a decent yanagiba can be had in the $140 range.