Shiro Kashiba is typically faithful to Japanese traditions, but he's lately taken to using Western-style knives for slicing fish and vegetables.
"We have to sharpen every day, but I'm getting lazy," the septuagenarian Kashiba confessed to a crowd gathered at the Nagomi Tea House for a recent sushi lesson. "So if ever I feel it down, then I sharpen."
The problem, Kashiba continued, is that one-sided Japanese knives can only be sharpened with a stone, which he described as a more laborious process than sharpening knives with a honing steel. As a result, "we're using lots of Western-style."
Japanese knives are made of hard carbon steel to support their extremely thin edges. The design's consistent with the Japanese belief "that cutting food without any crushing is essential to retaining its natural flavor," as Cook's Illustrated explained it.
Over the last few years, though, an increasing number of high-end knife producers in the East and West have started manufacturing hybrid knives with straight edges, slim cutting angles and blades which can be sharpened on both sides. The stainless steel "Western-style" knives have garnered positive reviews, but Olympia's Bob Kramer - one of 120 master bladesmiths in the world - says he hasn't seen any evidence of an industry-wide shift.
"I have been to several very high end sushi places in Tokyo where I know the house has been given Western-style stainless knives in the hopes that they would use them on a regular basis," Kramer says. "But when I visited, they were using their traditional high carbon sushi knives."
Kramer, who sells his knives through Kramer Knives, adds that it's not only Japanese-trained chefs who are sticking to carbon.
"Lots of American chefs have moved to using mostly high carbon blades, so go figure," he says.
Whether their blades are made from carbon or steel, knives remain the most important tool in a sushi chef's arsenal.
"This is part of my hand," Kashiba says of the knife he uses while demonstrating how to slice a mackerel.