Chef's knife



In cooking, a chef's knife, also known as a cook's knife, is a cutting tool used in food preparation. The chef's knife was originally designed primarily to slice and disjoint large cuts of beef. Today it is the primary general utility knife for most Western cooks.

A European chef's knife generally has a blade 20 centimetres (8 inches) in length and a broad 4 cm (1½ in.) width, although individual models range from 15 to 36 centimetres (6 to 14 inches) in length and may be as slender as 2 cm (¾ inch). Longer and wider knives are more frequently called chef's knives, whereas shorter & more slender knives have a tendency to be called cook's knives. The shortest and narrowest knives overlap into the general utility kitchen knife category that are too narrow to have a heel to the blade, like the smaller paring knife.

There are two common types of blade shape in western chef's knives: French and German. German-style knives are more deeply and continuously, but gently curved equally along the whole cutting edge and the spine - a symmetric elongated arrowhead; whereas the French style is not symmetrical and has an edge that is straighter, until the end and then curves strongly up to the tip. This asymmetric style of blade is synonymous with the renowned Occitan French Laguiole knife and Opinel knife; the Laguiole is the template for the modern steak knife.

Japanese kitchen knives differ from the European style as the latter typically have a thickened heel at the base of the blade where it meets the handle at the bolster. This heel is often shaped into the handle's form at the bolster. This can clearly be seen in the photograph above. The handle is typically bi-laterally flatted to allow for it to be rivetted together through the tang, whereas the oriental style typically has an off-circular cross-section. In Japanese kitchen knives, the blade and tang has little difference in thickness throughout it length, except at the tip when sharpened - there is no bolster - it is inserted into the handle with a separate collar to hold the assembled knife together.

With modern kitchen knives, these distinct styles have merged to a degree and particular characteristics have been swapped between the two regions, as can be seen in the photograph of the kitchen knife below.

Japanese kitchen knives have come under Western influence since the Meiji era, and many hybrid versions are available. The gyuto (牛刀 ぎゅうとう) 'beef knife' is the Japanese term for a French (or Western) chef's knife. The gyuto were originally, and sometimes still called yo-boucho 洋包丁 meaning 'Western chefs knife'.

The santoku 'three-virtue' knife is a style hybridized with traditional knives for more functionality. It is smaller, lighter and sharper with a different blade shape.

The Chinese chef's knife is completely different and resembles a cleaver. It is, however, functionally analogous to the Western chef's knife in that it's a general-purpose knife not designed for breaking bones.

A modern chef's knife is a multi-purpose knife designed to perform well at many differing kitchen tasks, rather than excelling at any one in particular. It can be used for mincing, slicing, and chopping vegetables, slicing meat, and disjointing large cuts.

Physical characteristics


Chef's knives are made with blades that are either forged or stamped:


 * Forged: A hand-forged blade is made in a multi-step process by skilled manual labour. A blank of steel is heated to a high temperature, and beaten to shape the steel. After forging, the blade is ground and sharpened. Forged knives are usually also full-tang, meaning the metal in the knife runs from the tip of the knifepoint to the far end of the handle. Commercially made forged knives are struck in a power hammer to produce features such as the bolster.
 * Stamped: A stamped blade is cut to shape directly from cold rolled steel, heat-treated for strength and temper, then ground, sharpened, and polished.

The blade of a chef's knife is typically made of carbon steel, stainless steel, or a laminate or folded sandwich of both metals, otherwise it will be a glass-like ceramic:


 * Carbon steel: An alloy of iron and approximately 1% carbon. Most carbon steel chef's knives are simple carbon iron alloys without exotic additions such as chromium or vanadium. Carbon steel blades are both easier to sharpen than ordinary stainless steel and usually hold an edge longer, but are vulnerable to rust and stains. Some professional cooks swear by knives of carbon steel because of their sharpness. Over time, a carbon-steel knife will normally acquire a dark patina, and can rust or corrode if not cared for properly by cleaning and lubricating the blade after use. Some chefs also 'rest' their carbon-steel knives for a day after use in order to restore the oxidizing patina, which prevents transfer of metallic tastes to some foods. While some cooks prefer and use carbon steel knives (especially in Asia and the Middle East), others find carbon steel too maintenance-intensive in a kitchen environment.
 * Stainless steel: An alloy of iron, approximately 10–15% of chromium, nickel, and/or molybdenum, with only a small amount of carbon. Lower grades of stainless steel cannot take as sharp an edge as good-quality high-carbon steels, but are resistant to corrosion, and are inexpensive. Higher grade and 'exotic' stainless steels (mostly from Japan) are extremely sharp with excellent edge retention, and equal or outperform carbon steel blades.
 * Laminated: A laminated knife tries to use the best of each material by creating a layered sandwich of different materials, such as using a softer-but-tough steel as the backing material, and a sharper/harder – but more brittle – steel as the edge material.
 * Ceramic blades hold an edge the longest of all, but they chip easily and may break if dropped. They also require special equipment and expertise to resharpen. They are sintered to shape with zirconium oxide powder. They are chemically non-reactive, so will not discolour or taint / change the taste of food.

Handles are made of wood, steel, or synthetic/composite materials.

Edge
The edge may be ground in different ways:


 * a double grind, V-shape, with either a single or double bevel
 * a convex edge
 * a hollow-grind with a concave edge
 * a single grind or chisel edge - resulting in a 'handed' knife, in most cases ground for right-handed cooks - which is typical in Japanese knives, termed kataba, but very rare in European.

In order to improve the chef's knife's multi-purpose abilities, some users employ differential sharpening along the length of the blade. The fine tip, used for precision work such as mincing, might be ground with a very sharp, acute cutting bevel; the midsection or belly of the blade receives a moderately sharp edge for general cutting, chopping and slicing, while the heavy heel or back of the cutting edge is given a strong, thick edge for heavy-duty tasks, for example disjointing beef. This differential sharpening suits European chef's knives with the heavy heel of the blade at the base at the bolster.

Technique
Technique for the use of a chef's knife depends on how well the knife is balanced as well as an individual stylistic preference. For more precise control, especially with longer heavier knives, most cooks prefer to grip the blade itself, with the thumb and the index finger grasping the blade just to the front of the finger guard and the middle finger placed just opposite, on the handle side of the finger guard below the bolster. This is commonly referred to as a 'pinch grip'. Those without culinary training often grip the handle, with all four fingers and the thumb gathered underneath.

For fine slicing, the handle is raised up and down while the tip remains in contact with the cutting board and the cut object is pushed under the blade.

Another technique is to hold the food being cut with one hand and to run the flat of the blade along the knuckles, utilising them as a guide. This enables the efficient use of both the curvature and the length of the blade's edge to execute the cut.