During the earliest days of orange cultivation, orange peels were more prized than the bitter fruit they protected. The essential oils extracted from orange peels were often used in medicines for indigestion and other maladies. Cooks during the Middle Ages were more likely to use dried orange peels as seasonings than to serve the fruit or the juice. It wasn't until sweet oranges were introduced in Spain and Italy that the rest of the orange received any recognition. Even today, there are perhaps more uses for orange peels and the oils they contain than there are for the rest of the fruit.
One use for orange peels is as a dried seasoning. Using a zester removes only the thin upper layer of orange peels, not the lighter coloured pith. The orange zest is usually left to dry overnight before being stored in airtight herb bottles. The orange zest can then used to enhance other flavours in desserts, gravies, sauces, and even some meat dishes. Dried orange peels can also be sprinkled as a garnish.
Another use for orange peels is as a candied dessert or accent. Orange peels can be boiled in sugar water until they become nearly translucent. Once allowed to dry, or placed in a food dehydrator, the candied orange peels can be eaten as a snack or combined with other dried fruits as an unusual salad. Different recipes for candied orange peels are available, but generally they involve the entire peel and pith, with several boiling sessions and a drying stage.
Outside of the kitchen, there are a surprising number of uses for orange peels. One unusual use for dried orange peels is as kindling for fires. The orange oils found in the peels are flammable, but they burn more slowly and steadily than common kindling material such as newspaper. Orange peel has the advantage of creating a pleasant odour as it burns.
Another use for orange peels is air freshening. Combine dried orange peels, cinnamon sticks, lemon peels, and flower petals in a simmering pot of water. As the steam leaves the potpourri, the air should become much more fragrant. Orange oil, derived from orange peels, is often used in commercial air fresheners and furniture polishes.
The essential oils found in orange peels are also used as insect repellents. To discourage ants from entering your home, experts suggest using a blended puree of orange peels and water directly on anthills and favoured pathways. Rubbing orange peels directly on the skin is also said to be an effective mosquito repellent. Insects in general find the odour of orange oil offensive, which may be a natural means of protecting the fruit from would-be predators.
Small insects aren't the only living things affected by the smell of orange peels. Some experts suggest that a mixture of dried orange peels and coffee grounds will discourage neighbourhood cats from using a homeowner's yard as a litter box. Animals such as cats and dogs are territorial, using scent cues to orient themselves. The overpowering smell of orange oil and coffee overrides their usual litter box signals.
So there you go. The people down the road could be using the peel for cooking, as a dessert, for kindling, air freshening, as an insect repellent or to ward off cats.