Zest and Peel
First, don't confuse citrus zest and citrus peel. Zest refers to just the thin, colored outer skin, while peel refers to the entire skin, including the outer skin and white pith.
There are three different methods for zesting any kind of citrus. What sets them apart is the tool you use to get the job done and how you want to use the zest.
But no matter which method you use, the key to good zest — whether you're working with oranges, lemons, limes, or grapefruits — is removing just the outer layer of skin and leaving behind the bitter white pith.
1. Zesting Citrus with a Microplane
Dragging the citrus fruit over a Microplane produces finely grated zest. Just be sure to turn the fruit as you go, as not to pick up any pith. These fine shavings are ideal for whisking into vinaigrettes, marinades, and citrus curd; mixing into batters and doughs for baked goods; and making citrus sugar.
2. Zesting Citrus with a Zester
The zester is a small hand-held kitchen tool that produces long, thin, curly strips of zest. These pretty curled shavings are best when added to sauces and used as a garnish.
3. Zesting Citrus with a Vegetable Peeler or Paring Knife
Using a vegetable peeler or a paring knife will create long, wide strips of zest. You may pick up some of the pith with this method, but it's an easy fix to cut it off with a knife. These larger pieces are ideal for adding to braises, infusing oils or simple syrup, and garnishing cocktails. It gives you all the flavor of the citrus fruit without all the grated zest. You can also julienne the zest into thin strips if smaller pieces are what you're after.