The essential oil is found in the peel of the lemon. It takes 75 whole lemons to produce one 15 ml bottle of essential oil. The processing of Lemon essential oil, similar to the processing of many other citrus oils, is a by-product of the fresh fruit industry. Fresh lemons that cannot be sold to the fresh market because of bruising or other aesthetic deficiencies are pressed for juice and essential oil. The juice and oil provide a dual use for leftover fruit.

The oil comes from “rasping” the peel (similar to a cheese grater that scratches the peel) on special equipment. The rasping equipment is submerged in water, just enough to cover the blades, and as it scratches the peel, the oil is released into the water. The fruit comes out looking something like a small, fuzzy ball with the peel completely removed. The oil is then separated from the water in a centrifuge, where it is processed at least twice. The fruit is juiced after the peel/oil have been removed.