The word frgrance covers a broad range of ingredients that give perfume and cologne their distinctive smell. Fragrance chemicals come from natural raw materials such as roots, barks, leaves, flowers, and seeds, or synthetic chemicals made in laboratories. Fragranced products may also contain solvents, stabilizers, diluents, UV-absorbers, and preservatives.
Safety legislation in the European Union (EU) and United States (FDA, Code of Federal Regulations Title 21) require that cosmetic ingredient lists be displayed on labels. However, fragrances are a special case, as the names of all perfume ingredients are considered trade secrets by fragrance manufacturers. In order to avoid the need for public disclosure of proprietary information, most perfumes list only the word “parfum” (EU) or “fragrance” or “fragrance mixture” (US).
Generally speaking, a perfume contains three structural parts—head, middle, and base notes—that provide a first impression, body, and lasting impression respectively after the application of the scent. Head notes are small light molecules that evaporate quickly; for example, the citrus scents of lemon, lime, and orange or berries.
Middle notes form the heart of a perfume; for example, linalool from rose, ylang-ylang from jasmine, and coumarin from orchid scents. The odorant compounds of a middle note remain in the air for 30 minutes or more after the evaporation of a head note.
Base notes add depth to a perfume, and for example are comprised of tobacco, amber, and musk. They are the longest-lasting components of a perfume and are derived from natural raw materials such as woods or animal pelts, or synthetically produced.