The art of perfume dates back thousands of years. People have been combining natural scents and human-made chemicals since ancient times to create the fragrances we wear today. From extracting oils to blending, aging and quality control, there is a lot that goes into making a perfume. There are more than 100 ingredients that can be found in perfumes. Most perfumes get their scent from natural aromatic raw materials which are extracted from plants, flowers, fruits and even woods. The other main ingredient are chemicals, called fixatives, which are used to keep the scents stable.
The first step in preparing raw materials for perfume is collecting them. This can be done in many ways, from gathering plant and animal scented oils through the expression or distillation process to using raw materials that are synthetically made by chemical synthesis. Synthetic oils can also be more stable and less expensive than natural oils.
Once the raw materials are gathered they need to be cleaned and filtered. After that they are prepared for blending, which can be as simple as pressing the ingredients until all of their oils are extracted or by using sophisticated processes like fractionation. In the latter case, different parts of a material can be isolated to change the overall odor of that part and therefore the perfume.
Perfumes are classified into five families based on their characteristic odor: Floral, Oriental, Woody, Aromatic Fougere and Fresh. They are further subdivided into a series of groups, each with its own subgroups, to give more specific classifications such as chypre perfumes or fresh fruity perfumes. It is also possible to make perfumes that are not classifiable into a family. These are known as bases and are created to be better scent approximations of a certain thing than a pure extract can be. For example, a perfumer might make a base that smells like the hydrangea flower and then present it for feedback.
As with music, perfume is constructed from sets of notes that create a harmonious whole. The top notes are the initial impression, the middle notes are deeper and the base notes are more long-lasting. The blending of the different notes is carefully planned with knowledge of how they will interact and the evaporation rate of each.
The final product is mixed with chemicals such as alcohol, which is used to dilute and carry the perfume, glycerol, which helps to thicken the oil, stabilize it and protect it from spoiling, and preservatives to slow down oxidation of the volatile fragrance compounds. The perfume is then bottled and labeled. It is often stored in a refrigerator due to the effect of cold temperatures on the scent molecules. This slows down the evaporation and preserves the perfume for longer, keeping it fresh and fragrant.