三徳, or Santoku — literally 'three virtues' — is a general purpose, modern Japanese knife and serves as an all-purpose knife for vegetables, meat and fish. It's also used for slicing, chopping and cutting, the secondary meaning of its title. It's the most accessible of the Japanese knives, having been developed far more recently than its three traditional forebears — the Nakiri, Deba and Gyūto — for precisely that purpose.
Care
Most of these care instructions apply to the traditional soft-steel Japanese knife I own, so I'm not yet making a distinction here. I will add relevant stainless advice if I have to in future.
Daily Practices
- I use wooden chopping boards with soft steel knives, after being recommended to avoid harder materials like stone, marble and bamboo.
- I always hand-wash and dry immediately after each use with a soft sponge and a tiny amount of soap.
- Black spots and patina are normal and will help protect against rust. Reddish-brown discolouration is rust, though, and should be removed immediately.
- I sharpen as soon as the blade begins to feel different, even if it seems 'too soon'.
Rust Prevention
- Avoid contact with other steel objects.
- Wash and dry immediately after use.
- Do not leave to soak for long periods of time.
- Apply mineral oil regularly (every month or so) to the clean blade, wiping it down immediately.
To remove rust, use steel wool and mineral oil to gently scrub any spots or patches off. For long term storage, I apply mineral oil to the blade and wrap it in paper.
Sharpening
My knife, based on my usage, only needs to be sharpened once a week or so. A professional chef might need to sharpen it daily. I use Japanese sharpening stones, which generally fall into three broad types of different grits.
- 荒砥, Ara-to, which is a coarse stone of 120 to 600 grit. Coarse stones are for reshaping damaged blades.
- 中砥, Naka-to, which is a medium stone of 1000 to 1500 grit. Medium stones are for maintaining blades.
- 仕上げ砥, Shiage-to, the finishing stone, 3000+ grit. Finishing stones are for polishing blades.
Coarser whetstones should be prepared by soaking first. Finer ones may be damaged by extended soaking, so only splash them before use.
For dull blades, sharpen first using the coarse stone, followed by the medium stone and polish using the finishing stone. If the blade is regularly maintained and requires very little sharpening, skip the first step and use the medium stone first.