Before foods that require cooking are cooked or before foods that are to be eaten raw are served, they must be properly prepared, for their palatability and their value as food depend considerably on the way in which they are made ready for cooking or for eating. Of course, the way in which food should be prepared will depend on how it is to be served, but in any event all foods, for the sake of cleanliness, must first be washed with water or wiped with a clean, damp cloth.

The ways in which vegetables and fruits are made ready for cooking vary. Sometimes such foods are cooked with the skins on, and sometimes certain vegetables, such as new potatoes, young carrots and parsnips, vegetable oysters, etc., are made ready in an economical way by scraping off their skins with a knife. Vegetables are also peeled, and when this is done a very sharp knife with a thin blade should be used and as little of the food removed as possible. Still another way of removing the skins of such foods as tomatoes, nuts, and some fruits is by blanching. In this process, the skins are loosened so that they may be removed easily, either by immersing the foods in boiling water or by pouring boiling water over them and allowing them to stand in the water for a few minutes, but not long enough to soften them. Blanching used in this sense should not be confused with the same word when it means "to take color out" and has reference to a process of bleaching. Only when the word means "to remove the covering of" can it be applied to the peeling of tomatoes, fruits, and nuts. Vegetables and fruits may be cooked whole or they may be cut into chunks, or pieces, or into slices.

In order to get meats ready for cooking, it is necessary to wipe them clean and usually to trim off all unnecessary bone, fat, and skin. Meats may be cooked in large pieces or small pieces or they may be ground, depending on the cooking process to be used. Before cooking poultry and fish, they should be thoroughly cleaned and then trimmed and cut to suit the cooking process chosen. If desired, the bones may be removed from poultry or fish before cooking, and sometimes it is advantageous to do so. Cream and raw eggs may be whipped or beaten light before they are served or cooked, and after such foods as fruits, vegetables, meats, and fish have been cooked, they may be sliced, chopped, ground, mashed, or cut into dice, or small pieces