Lemon zest is the bright yellow part of the peel of a lemon. It is used in foods and as a garnish for both food and drinks. To obtain this zest, many cooks and bartenders employ the use of tool called a lemon zester or citrus zester. Using this tool, one can quickly and easily scrape the zest off of the citrus fruit.
Most zesters are roughly 4 to 6 inches (10 to 15 cm) long. They generally have a handle with a metal end that resembles a very small cheese grater. Fine holes on the metal end of this tool have sharp edges that remove the zest when it is dragged across the rind of the fruit.
The rind of a lemon, or just about any other citrus fruit, is typically made up of two layers. The pith is white and bitter, and it is sandwiched between the zest and the flesh of the fruit. Zest of a lemon is the bright yellow part of the rind. It is the thin outer layer of the rind, and it is packed with fragrant and flavorful oils and juices.
Before using a lemon zester on any type of fruit, culinary experts agree that it is important to wash the fruit and dry it thoroughly. The metal grating part of the lemon zester is then pressed on to the top of the fruit and dragged down the rind, often from top to bottom. Some more experienced zesters are able to make long continuous threadlike peels of zest, which are great for garnishes, by running this tool in a downward spiral around the fruit.
Besides a lemon zester, there are a few other cooking utensils that can remove the zest from a lemon. A paring knife can be used, but unless one is very experienced in this method, parts of the bitter pith are often still attached to the zest. A small cheese grater is also a popular substitute for a lemon zester, as is a vegetable peeler.
Lemon zest is used in a number of recipes, especially in baking. Many popular lemon tarts, pies, and cookies make use of lemon zest. Meats, salad dressings, and other recipes also call for this flavorful ingredient. When cooking the zest into a recipe, a person may have to chop up the long strips that she gets from a lemon zester. In cocktails, however, the long strips of zest make great twists and garnishes, and a lemon zester is considered to be an essential addition to other bartending equipment.