What is Special About a Sushi Knife?
Sushi is a Japanese dish made with rice and either vegetables or a seafood, with egg occasionally added. In the West the most common type of sushi is makizushi, a type of sushi where the filling is usually wrapped in a type of seaweed known as nori, with the rice either on the inside or outside of the nori wrapper. Sushi often makes use of raw fish, such as snapper or tuna, as a key ingredient.
When people in the West talk about a sushi knife, they are usually referring to a general sort of cutlery used for everything from slicing vegetables to cutting the final sushi roll. In this context, a sushi knife is distinguished from Western knives and some other Japanese knives by two main differences: material and sharpening.
Traditionally, a sushi knife would be made of an incredibly high-quality carbon steel, the same type used in the forging of katana, traditional Japanese swords. The average sushi knife one would find in a modern kitchen does not use such high-quality materials, instead using top-end stainless steel. The best modern sushi knives still rely on steel with a high carbon content.
The other large difference between a sushi knife and the average Western knife is the way in which it is sharpened. While nearly all Western knives are sharpened on both edges of the blade, a professional sushi knife is sharpened on only one edge, a style known as kataba. For right-handed knives, this is the right edge, and for the rarer knives made for left-handed cooks, the left edge is sharpened instead. Having only one edge of the knife sharpened allows for cleaner cuts and more precision, but learning to use only one edge is more difficult and takes many beginners some time to master.
Looking beyond the general term sushi knife, there are many different types of knives used in creating sushi. Each of these knives are designed in a way which allows them to excel at a specific type of cutting, with some particular fish species having knives designed exclusively to cut them.
The three main sashimi (fish) knives are: yanagi ba, fugu hiki and tako hiki. The yanagi ba looks similar to a Western paring knife, and is used for most fish. The fugu hiki is specifically designed to fillet the puffer fish, or fugu. Yanagi ba are longer, thin blades, used for octopus or squid. For fish beyond a manageable size, such as large tuna, special blades exist which may be in excess of six feet (2m).
Deba bocho are another type of sushi knife, much wider than yanagi ba, and somewhat resembling a Western carving knife. They are used to cut from thicker fish, but their primary purpose is for cutting non-seafood meats such as beef or chicken. The deba bocho is a large cleaver used for the rough cutting of fish, before using yanagi ba or another, smaller sushi knife to cut the fish into the thin strips used in sushi.
The unagisaki hocho is a knife designed specifically for filleting eel, a common sushi filling. The knife has a nearly-square shape, with a sharp point and right-angle at the tip. The point is designed to pierce the eel at the head so that the body may be sliced in one easy motion.
Vegetables are usually cut using one of two types of sushi knife, either the usuba bocho or the nakiri bocho. These knives are straight-edged so that they can slice vegetables easily with one cut, without the need to rock the blade or push it down. The blades are thin, to ensure a clean and precise cut without breaking the vegetables. Nakiri bocho are sharpened on both edges of the blade, making them more suitable for novices, while usuba bocho are sharpened only on one edge.
A simple all-purpose sushi knife may be found for under US$40 from many suppliers. Higher-quality and specialty knives may cost hundreds of dollars, and assembling a full kit of knives can be a massive undertaking. For most home users, a sushi knife sold by a trusted cutlery producer will be of suitable quality for everyday use without breaking the bank.
Written by Brendan McGuigan
