Whether Japanese or German, each type of knife has been influenced by its culture. The Japanese believe in having a perfect tool for an explicit purpose, and as such have many specific knives for specific tasks. Meanwhile, Germans value versatility and durability in their culinary efforts and therefore have designed knives that are good at many different undertakings. In the end, each knife has its own strengths and weaknesses. It’s not that one style of knife is better than the other — it’s just a matter of use and preference.
The Blade’s Steel
Your typical Japanese knife is known for its sharpness. A direct descendant from the samurai sword, these knives only have to lightly graze an object in order to make a slice or incision. The main reason they are so sharp is due greatly to the hardness of the steel used in the blade’s core. Japanese knives are constructed with steel that has a high carbon content, giving it anywhere from a high 50s to mid 60s on the Rockwell scale. Because of this, they hold their sharp edge well and for longer. However, caring for a sword with high carbon steel means they are more likely to rust.
Meanwhile, a German knife is known for being able to take a beating. They want a sharp edge, but also want to know that their knives are durable and easy to care for. They use softer steel throughout the blade’s core and surrounding, making them less likely to chip, break, and rust. However, because of the softer steel, they will never be able to hold as sharp of an edge as a Japanese knife, and you will need to sharpen more often. Ease of care comes with the cost of edge retention, and vice versa.
The Cutting Edge
First, let’s explain what is meant when talking about knives and their cutting edge. The angle of the knife is also referred to as the “bevel.” Most knives have a bevel on both sides, but some traditional Japanese knives have a single bevel, or even differing bevel sizes. Typically, however, when talking about knives that have a traditional bevel and a 10 degree angle, it means on both sides, making the total angle 20 degrees.
The bevel of a Japanese knife is smaller than a German knife, again making the blade sharper. The Japanese make both double beveled knives and single beveled knives. In either case, the angle of a bevel in Japanese knives are smaller than that of German knives. In Japanese knives, the bevels are typically anywhere between 7 and 8 degrees, allowing it to nicely slice through food, such as raw fish, without damaging the cell walls and therefore preserving the taste and texture. Again, they’re able to create this angle thanks to the hardness of the steel used. The Japanese value precision, and the angle of their knives allow for that.
German blades, however, are typically sharpened to around 10 degrees, making them not as sharp as a typical Japanese knife. Yet with their wider bevel they are able to compensate for the sharpness by being versatile and weighted. They may not have the cutting edge to slice through tough objects, but they have the strength to.
The Weight of the Knife
Culturally, the Japanese are not known for their strength. In war, they relied on battle technique and the sharpness of their samurai swords to defeat their opponents. In cooking, their strategy is similar. By forging a sharp cutting edge on their knives, they can cut through objects without having to put force behind the blade.
Typically German knives are heavier, meaning that while they may not have the extremely sharp edge that Japanese cutlery is known for, they utilize the weight of the knife to do the work for them. This is the reason why chefs who are used to German knives prefer using knives that are heavier.