A kitchen knife is any knife that is intended to be used in food preparation. While much of this work can be accomplished with a few general-purpose knives – notably a large chef’s knife, a tough cleaver, and a small paring knife – there are also many specialized knives that are designed for specific tasks. Kitchen knives can be made from several different materials.
Carbon steel is an alloy of iron and carbon, often including other elements such as vanadium and manganese. Carbon steel commonly used in knives has around 1.0% carbon (ex. AISI 1095), is inexpensive, and holds its edge well. Carbon steel is normally easier to resharpen than many stainless steels, but is vulnerable to rust and stains. The blades should be cleaned, dried, and lubricated after each use. New carbon-steel knives may impart a metallic or “iron” flavour to acidic foods, though over time, the steel will acquire a patina of oxidation which will prevent corrosion. Good carbon steel will take a sharp edge, but is not so hard as to be difficult to sharpen, unlike some grades of stainless steel.
Stainless steel is an alloy of iron, approximately 10–15% chromium, possibly nickel, and molybdenum, with only a small amount of carbon. Typical stainless steel knives are made of 420 stainless, a high-chromium stainless steel alloy often used in flatware. Stainless steel may be softer than carbon steel, but this makes it easier to sharpen. Stainless steel knives resist rust and corrosion better than carbon steel knives.