Thoughts On Rust
Note: This article is not about `rust-lang` but the actual rust that develops on knife blades
Your kitchen knife is very likely made of steel, an alloy that combines Iron, carbon, chromium, nickel and maybe even other metals. Chromium and nickel percentage affects the rust resistance property of the steel. The level of rust resistance is one of the major differences between the modern Western and Japanese kitchen knives and a common worry when some home cooks and professionals look to purchase their first Japanese knives.
Western chef knives are usually made of stainless steel. Higher chromium and nickel content makes western chef knives effectively resistant to rust. However, this high rust resistance property is no guarantee for a western knife to be free of rust; it is more accurate to interpret “stainless” as “stain less”.
Japan does not have a long history of consuming meat; the design of Japanese single bevelled kitchen knives largely revolves around processing vegetables and fish. As fish flesh is a lot more delicate than meat, especially since Japanese culture values food presentation, kitchen knives with extremely hard and sharp edges are invented for Japanese kitchens. Japanese knives are usually made of steels which are higher in carbon and lower in chromium and nickel content; this results in sharp and long-last edges in Japanese knives, and they can be effectively sharpened to restore the edge sharpness. One trade-off is made for this use case, though: Japanese knives rust easily.
Understanding this trade-off, Japanese chefs don’t seem so worried; they fight the rust with, you guessed it, kitchen linens/towels and the deliberately developed habit of wiping down their knife blades as often as they can.
I would argue that this habit is worth developing even for average home cooks. When I take proper care of my tools, I tend to take pride of my craft and end up enjoying it more. I bought my first cast iron pan a few month ago to replace an old stainless steel frying pan. Concerned about the cast iron pan getting rusty if left in the kitchen sink, I have been keeping a great track record of not leaving a full kitchen sink of dirty utensils unattended after cooking ever since.
Even with great care, knives could still develop rust in the moist environment. But worry not, with a few simple tools, it is not difficult to remove the rust from the blade and restore the knife anew.
- Rust eraser can easily remove most of the surface red rust
- Use sand paper to treat the more persistent black rust or patina
- Use a rough whetstone to repair the blade edge eroded by rust
I hope this post can help you make more informed purchase for your next knife. Leave a comment if you have any questions :)