Comparing Single-Edged and Double-Edged Blades

Last night, I had a small errand to run, so I headed over to Uedaya. I’ve finally figured out the fastest and safest route to get there on my moped, and it’s such a joy to travel comfortably to Uedaya these days.

I planned to just take care of my business and head back quickly, but a slightly tipsy regular insisted, “Don’t leave so soon! Stay and chat with us!” It was a bit forceful but endearing (Lol).

Our conversation shifted from the essence of Japanese knives to the differences between single-bevel and double-bevel blades. The topic of cut surface quality came up, which can be hard to grasp for most people.

Amidst all this talk, Ueda Shihan decided to demonstrate by cutting a new onion with a single-bevel usuba knife and a double-beveled gyuto.

Just look at how cleanly the single-bevel knife cuts! The difference is so clear you can see it in the photos. Check it out!

↑ Here’s a cross-section of onions cut with a chef’s knife!

↑ Here’s a cross-section of onions cut with a KamaUsuba knife!

After a day’s work, we conducted an experiment with kitchen knives, and the difference was quite noticeable. The chef’s knife clearly left a rough cross-section, while the Kamausuba knife resulted in a clean cut. Even when tasted without rinsing, the difference was stark. As soon as I tried the chef’s knife, the onion’s juice attacked my palate! In contrast, the Usuba knife offered a momentary sweetness, followed by the onion juice spreading gently upon chewing.

There are various factors at play here—steel type, compatibility with the whetstone—but fundamentally, I felt the difference in power between double-bevel and single-bevel knives. Our regular customers were equally convinced upon seeing these results and left in a slightly tipsy mood (＾＾).

Did you know onions cut with a dull knife make you cry more easily? It’s because they crush cells instead of cleanly slicing through. A sharp knife cuts cleanly, reducing the spray of onion juice. Makes sense, right? (＾＾)ｂ

Just to clarify, with careful and patient sharpening, even a double-bevel Western knife can achieve a cross-section similar to that of an Usuba. However, this may raise doubts about its durability. Single-bevel knives may be trickier to handle, but the results are worth it, don’t you think?

• 2010-06-18