The assembly of a perfume requires both art and science in the understanding of olfaction, extraction of scented elements from botanicals, behavior of chemical components, and careful blending of scents to achieve the desired composition.

    Fragrance design is as dependent on the creativity of chemists as on the perfumers themselves. When an odour cannot be extracted from a natural product for environmental or technical reasons, chemists can synthesize the fragrance note by developing new ingredients.

Collection of Scents

    A perfumer's quest to create a fragrance often begins in a natural place,

such as a seashore, a field of flowers, or a tropical forest. At one time, perfumers collected the scents of a place by employing a technique called "enfleurage." The perfumer pressed a natural specimen, such as a lily, into several layers of purified fats. Back at the lab, the lily sat for several hours, delivering some of its aroma to the fat. Then the perfumer washed a solvent--a liquid that dissolves another substance to form a solution--over the fat, which captured the lily's aromatic molecules.

    A modern perfumer collects nature's aromatic molecules using headspace technology, which consists of a glass dome connected to a battery-operated pump and a filter. To capture the scent of a lily, a perfumer need only place the dome over the flower and turn on the pump. The pump sucks the air around the lily through the filter, and the filter captures the lily's aromatic molecules. Washing the filter with a solvent places those molecules in a solution.

Classification of Scents

    Scents are classified as notes based on their olfactory character. Top notes are those that are detected and fade first providing freshness to the blend. They are light scents that are usually citrus or grasses lasting 5-10 minutes. Middle notes are those that last several hours and are the most prominent within the fragrance. These are usually combinations of spicy, floral or fruit scents. Base notes give a perfume depth, last the longest and are generally animal or woodsy notes. A perfume is a unique mixture of top, middle, and base notes designed to give a particular harmony of scents.

    Perfumes generally fall into several families based on the dominant note. These include spicy, leather/tobacco, woody, mossy, citrus, floral, and oriental, any of which may be formulated for men or women, although florals are not generally used in men's fragrances. The floral scents of jasmine and rose are used in 83% and 75% of women's perfumes, respectively. Many of today's fragrances contain vanilla or a synthetic form of vanilla. Most men's fragrances will contain patchouli from India or Indonesia. Musk or synthetic derivatives is used in 90% of all fine fragrances.