Arguably, the first cooking implement created was the knife. Knives were used for hunting and gathering, as well as for food preparation. Skipping forward a few millennia, the knife remains one of the most important tools, if not the most important tool, in the kitchen. As important as the knife is, I am amazed when I visit home kitchens, both in France and America, to find a plethora of poor quality knives. Plus the knives are poorly treated, and their owners often don’t know how to use them properly. And my experience in professional kitchens hasn’t always been much better.
Maybe my expectations are too high? After all, most knives aren’t sold with instructions for use. And if they were, who would read them? No one shows us how to use a knife when we are young. Maybe there’s some instruction in a cooking class, but was the instruction correct? (I’ve seen a lot of cooking teachers use knives incorrectly, too!) Maybe it’s all a conspiracy of the “Band-Aid” cartels!
One proficiency that is required of French cooking students before they can apprentice in a restaurant is that they have excellent knife skills. Often, they don’t seem to know much else, but I’ve been amazed at their abilities with a knife.
On the next few pages is “Knife Basics 101.” I’ll first review some knife anatomy and design. That page is followed by one with a brief discussion of knife materials — which are best and why. Next, there’s my version of how to use knives — the most important part of this article. Finally, there’s some information on caring for, storing, and sharpening knives.
This is not meant to be an exhaustive dissertation on knives, but a highly opinionated overview. If you have specific questions, please go to the comments section and send me an email. If you’d like specific information as to how to cut various fruits, vegetables, meat, poultry, or fish, check out Knife Skills Illustrated, my “User’s Manual” for knives.
There’s more to a knife than a blade and handle! The tip of the knife is used for puncturing tough materials, such as the skin on some vegetables. It’s also used for cutting very thin items. The most used part of a knife is the middle of the cutting edge. It works best when the knife is moved with a forwards and backwards motion. The best cut is achieved by moving the blade parallel to the cut. The end of the cutting edge near the handle is called the heel. The heel is used mostly for heavy cutting, or when maximum leverage is needed. It is most efficient for making quick, coarse cuts, and for jobs which require strength or pressure. Additional force for cutting with the heel is sometimes applied with the palm of the hand not holding the handle of the knife. The spine of the blade should be smooth with rounded edges. If the edge isn’t rounded, the user will develop a blister on the thumb-side of the forefinger with heavy use.
The bolster is a thickened portion of the blade just before the handle. Bolsters are a feature of forged blades where the manufacturing process starts with a thicker piece of metal than when the blade is stamped. Because the bolster tends to extend all the way to the cutting edge, sharpening the cutting edge all the way to the end of the heel can be difficult with many standard methods of knife sharpening. Some chefs believe that the bolster gives a knife better balance. The bolster also helps prevent the user’s hand from slipping onto the blade. On some knives without a bolster, especially those with molded handles, there’s often a guard at the blade end of the handle that functions in a similar manner.
The part of the blade that extends into the handle is called a tang. Better quality knives with riveted, two-piece handles have a “full” tang that extends all the way to the butt of the handle. The extension improves the balance of the knife. For knives with a molded handle, a round, pointed, rat-tail tang is used. It is wholly contained within the handle.
Handles come in both natural materials, such as wood, and in molded materials. Some modern knives are also being manufactured with hollow metal handles that are welded to the blade to give the appearance of the knife being made out of a single piece of metal.
Years ago, cooks only had a couple of knife designs from which they could choose. Now, there’re more knives of different designs for sale than one could ever need. Still, for most cooking, a good, large knife and a good, small knife are all one really needs. With a good, sharp, 26 cm (10 in) chef’s knife and a very small paring knife, one should be ready to conquer the world. (Because my background is firmly rooted in Chinese cooking, I use a Chinese slicing cleaver instead of a chef’s knife. For a paring knife, I use a German mushroom fluter which I originally bought for carving vegetables for decorating Chinese dishes. When working in restaurant kitchens in France, I use a chef’s knife and a paring knife.) When purchasing a chef’s knife, it’s important to remember that French knives have a straighter cutting edge than the German and American versions. The French design requires less “rocking” of the blade when slicing to ensure that one cuts cleanly to the cutting board. The French often use a “bird’s beak” knife as a paring knife because the tip is at a better angle for peeling. For example, when peeling an onion, where the tip is used to lift the skin from the flesh, the angle of the tip is slightly better with the “bird’s beak” knife.
Other knife designs that I find useful are a serrated bread slicer, a boning knife, a filleting knife, and a ham slicer. Because of the serrated blade, a cheap knife seems to work just as well for bread as an expensive one.
A boning knife is a nice luxury for boning small poultry and other meats. The flexible blade with the smaller tip makes it easier to cut close to the bone. For larger poultry, I still prefer a chef’s knife, or my Chinese knife, because the heavier weight makes it easier to disjoint the fowl. A boning knife is designed for cutting meat on the bone; it’s very difficult to use on a cutting board because the cutting edge curves outward near the handle.
What the boning knife is to meat, the filleting knife is for fish. The thin flexible blade makes it easy to skin fillets. The long, straight shape of the blade allows the user to use the tip of the blade to delicately separate flesh from bone. The small handle — the same size as a paring knife handle — of a filleting knife helps to encourage a delicate touch.
The ham slicer has a round tip because only the center of the cutting edge is used with this knife design. The sides of the blade have slight indentations that reduce surface tension between the blade and the foodstuff being cut. This means there is less drag on the blade as one “saws” through the food. I find it especially useful for slicing terrines and solid, fatty items like foie gras.
There’re lots of other knife designs other than the six mentioned above. It is possible to have a huge collection, but only a couple are really essential.
Most knife blades are made of steel. (There’re a few specialty knives made with ceramic blades — zirconium carbide and zirconium oxide.) The steel blades can in turn be divided into three broad groups: carbon steel, stainless steel, and high carbon stainless steel.
Knives with plain stainless steel blades are usually inexpensive — which is good because they usually are dull when purchased and never get any sharper. Food-service grade stainless steel is too soft to make an effective blade because it cannot hold an edge. These knives were very common a few years back, but are available less and less (except in the local supermarket or hardware store).
Knives with carbon steel blades have a number of advantages and a couple of disadvantages that have been their downfall. Blades made from carbon steel, sometimes referred to as high carbon steel, can be sharpened to a very keen edge. Carbon steel blades are not quite as hard as high carbon stainless steel so they must be sharpened more often. The blades are also more flexible than those made of high carbon stainless steel. Chefs who use knives with carbon steel blades swear by them, but they also know how to take care of them. Carbon steel will oxidize — in other words, tarnish or rust. These knives must be cleaned and dried immediately after use. If not used daily, they should be given a light coating of vegetable oil to prevent oxidation.
Knives with high carbon stainless steel have become the standard nowadays. Besides carbon, the steel is usually alloyed with trace amounts of chrome, vanadium, and molybdenum to increase its hardness. Since these blades are slightly harder than carbon steel knife blades, they hold an edge better, although one that isn’t quite as sharp. The edge is a bit more brittle, too. This means that more care has to be taken to avoid bones and other hard materials when using these knives. But these blades won’t oxidize — a major selling point.
At the other end of the knife is the handle. Formerly, handles were made of wood or bone. Today, most commercial knives are made of moldable materials. Sometimes the handle material is attached to the knife with rivets in the old-fashioned manner, but often the handle is now molded in place. There are still knives sold with wood handles, but these are becoming less and less common in the commercial kitchen. Also, some of the high-end knives are now being manufactured with hollow metal handles that are welded to the blade and finished to give the knife a one-piece appearance.
I believe that the choice of handle material is largely a personal one. The knife must feel good in the user’s hand. Also, finding a knife with a carbon steel blade has become very difficult in most areas, so high carbon stainless steel blades dominate the market nowadays. I have found some high-quality knives with carbon steel blades in France, but even there they are becoming less common.
My biggest frustration with knives, the reason I started to write this article, is that watching people use knives incorrectly affects me like dragging a fingernail across a chalkboard. I realize that no knife comes with instructions for use, but why can’t people learn to use them correctly — or at least the way I think they should be used?
I believe that there are essentially three ways to hold a knife, depending on the knife and what is being cut. For cutting against a board or the bone, the knife should generally be held with the blade between the thumb and the forefinger. The other three fingers are used to grip the handle. For cutting hanging meat, the knife needs to sometimes be held in dagger fashion for proper leverage. For peeling and turning with a small knife, the knife is held by the fingers with one or two gripping the blade. The thumb, in this situation, is used to support the item being cut.
Although some force is required when using a knife, by moving the blade parallel to the surface being cut, the force is reduced. With this back-and-forth, parallel motion, food is sliced. If there is no motion other than perpendicular to the surface, the food may be crushed more than cut.
The illustrations below demonstrate three methods of knife use.
When cutting small items with a large chef’s knife, the tip of the knife is left in contact with the cutting board. The knife is moved forward and angled down simultaneously to cut the food. Once the cut is made, the handle of the knife is angled upward and the blade is slid backwards to its original position. Once a rhythm is developed, it’s possible to cut small, long items, such as green onions, herbs, chives, etc., very quickly with this method. Also, this method is best accomplished with a long knife blade. A short blade requires too much of an angle when starting the cutting cycle to gain much speed.
When cutting larger items with a chef’s knife, the blade still starts at an acute angle to the cutting board, but the blade tip is not in contact with it. As the cut proceeds, the blade is brought parallel to the board as it is move forward. At the end of the cut, the motion is reversed until the blade is once again on top of the food being cut. Here a long blade is an advantage because more forward motion can be achieved relative to the downward motion of the blade. This makes cutting easier.
When cutting or peeling small items with a paring knife, the knife is held closely with the fingers and the food supported with the thumb. Although for some items, such as shallots, moving the blade back and forth makes the cut easy, care must be taken near the thumb not to cut it. This is accomplished by stopping the back and forth “sawing” just before contact is made with the thumb.
Knives don’t require much care to last a long time, but they can’t be ignored either.