Let us begin by disclaiming a common belief: the santoku, a legendary type of Japanese knife, is not a "sushi knife". Or better, it is not specially made for sushi. Rather it is a more versatile chef's knife in the Oriental tradition. The fact that it is also used to slice raw fish is thanks to its ultra-sharp blade, thanks to which the santoku has become so famous and popular. The name means "three virtues", indicating its three main functions: cutting, slicing and chopping.
The power of the blade
Beyond all the words we could use to describe it and that would never be enough, the blade is the distinguishing element of the santoku. Compared to a European blade, its metal contains more carbon, is thinner and thus lighter. Special heat processing makes the blade highly resilient, meaning it keeps its edge for a long time. This edge is obtained by sharpening at an acute angle of about 16 degrees.
Over time, even the santoku has been subject to a certain evolution, bringing it to now exist in three types. The classic style has a steel blade. Then there is a blade in Damascus steel. The third type is fitted with a (yes, of course!) ceramic blade. Obviously, purists do not consider ceramics to be an option. They stick to stainless steel or Damascus steel. The latter is stronger and more costly to make, and the word Damascus is not quite exact. This blade is called san mai. It is made using a very similar technique, but one that is typically Japanese, meaning that although the san mai is a variation on the classic santoku, it is nonetheless faithful to its origins. So if you happen to come across a blade with the characteristic mottled pattern on the surface, you might want to take it into consideration.
Where are santoku knives fabricated?
Of course it goes without saying that if you wish to acquire this type of knife, the first thing to do is find out where it was fabricated. Unfortunately, it is frequent to happen upon "Japanese-style" santoku knives produced in other countries where they are built to lower standards. Therefore, carefully check where the knife was made.
Then there is the aspect of honing. The traditional santoku is sharpened on one side only, but for quite some time now, there have been two-sided blades on the market. They are more precise, but require more care and maintenance. Remember, a true santoku must be handled in a ritual way, not only to avoid getting hurt, but also because the blade is as sharp as it is delicate. The santoku is unforgiving when it comes to error. It allows you to obtain very thin slices of fish or beef tartare with a fine yet firm grain, but watch out for bones! If the blade accidentally hits one, it will need to be sharpened anew, strictly with a special hone or whetstone – never with an automatic sharpener. The santoku has no point. The blade of the typical Japanese knife ends in a curved tip that meets the sharpened edge.
How to handle a santoku knife
Then there is an actual cult based on handle materials, but the truth is that here, minimalism is key. Wood for the traditionalists, fibreglass for the modernists, but plastic? No thanks. There's more variety in the length of the blade, some of which come with a hollowed Granton edge to prevent moist foods from sticking to it.
Although no length is typical, the range is between 13 and 30 centimetres. For the sake of delicacy, it would be better if it did not surpass 18 centimetres. One final note regards the cost. There is no "right price" for a santoku, but it should be clear to buyers that this model is not run of the mill.