In last week’s recipe (Mini Lemon Pound Cakes), one of the ingredients listed was “zest of one lemon,” which brought about the question — what is zest? Zest is a fancy way of referring to the skin or rind of citrus fruits (lemons, limes, oranges, grapefruits, kumquats).
Anyone who’s ever mistakenly tasted the skin of an orange knows the taste is bitter at best, but the carefully removed thin layer of colored skin can actually provide lots of concentrated citrus flavor to food. The bitterness comes from the thick, white layer underneath, known as pith.
You can remove zest in a number of ways. You can purchase a zester, a small handheld tool that removes thin strips of zest when pulled across the outside of the fruit, or use a microplane (the long silver tool in the above picture) or a regular grater. For larger pieces of zest, which are often used as garnish or to add flavor to soups or sauces, use a vegetable peeler to separate it from the flesh of the fruit.
A couple of tips, grate gently to make sure you’re only getting zest and not pith. Once the white becomes visible, turn the fruit and begin grating in a new spot. When measuring zest, don’t pack it too tightly in your measuring spoons or you may end up with more citrus flavor than your recipe calls for. If you’re using a microplane or grater, be sure to check the back or non-cutting surface to remove any zest that sticks.