Lemon rind, also known as lemon zest, is the thick, leathery outer skin of the fruit and protects its juicy pulp and seeds. Once a lemon is juiced, this protective layer is typically discarded. But there are several ways to repurpose lemon rind, and bakers have long used it as a colorful, edible and fragrant decorative accent on baked goods, such as cakes.
The bright yellow rind and the underlying white spongy pith of the average lemon is usually 1/4-inch to 3/8-inch thick, according to Purdue University's Department of Horticulture. The yellow rind contains oil glands that give off the fragrance of the lemon when they are cut to produce lemon rind zest or strips. When preparing the rind of a lemon for use as a decorative accent, it is best to remove as much of the underlying bitter-tasting pith as possible. Lemon rind can be cut into strips that can be curled or knotted, grated into lemon zest or sliced with the fruit attached, cut halfway through on one side and twisted to make lemon twists that can stand on top of a cake.
Lemons continue to ripen after they are harvested, so growers coat them with a water-emulsion wax that retards loss of moisture, reducing the risk of shriveling and extending the shelf life of the fruit, according to Guyana's Ministry of Fisheries, Crops and Livestock. Lemons whose rind will come into contact with food should always be washed to remove this post-harvest wax and any remaining insecticides. Washing with a sponge and soapy water followed by rinsing and towel or air-drying will remove these surface residues. The rind of a lemon can be dried or frozen after it is zested when stored properly.
Zesters, microplane zesters, box graters, vegetable peelers and paring knives can all be used to cut lemon rind in preparation for its use as a decoration on cakes, according to the What's Cooking America website. Zesters, paring knives and vegetable peelers are used to make the more substantial, thin, julienned strips that can be curled, spiraled and knotted before being placed on top of a cake. Microplane zesters and box graters are used to make the more finely textured powdery grains of lemon rind zest that are sprinkled on top of baked desserts.
The oil that is produced by lemon peel oil glands has been known to cause contact dermatitis rashes, a condition that can become chronic if the person afflicted handles lemons frequently, according to Purdue University's Department of Horticulture. People who suck on lemons regularly can develop rashes around their mouths. Woodworkers with a sensitivity to the oil can exhibit skin reactions when working with the wood of lemon trees.