Other perfume making techniques
Supercritical carbon dioxide extraction consists of using a carbon dioxide by-product as a solvent. Since this solvent is much easier to eliminate production costs are lowered.
Cold expression is used only for citrus fruits (orange, lemon, bergamot etc) where the essential oils are contained in the peel. When scraped manually or mechanically these peels yield a mixture of scent-bearing oil and water, this mixture is then centrifuged, filtered and finally concentrated.
Infusion is principally used for dried materials (vanilla pods etc), which are soaked in solvents, that do not need to be eliminated afterwards, for several months. With the advancements in chemistry, this costly process is now rarely used.
New chemical processes help fulfil both the ever-increasing requirements of the market and the desire to ensure that the composition and quality of perfumery products remain consistent.
Fractionation consists of isolating the various components of an essence. The isolate components are used to produce perfume ingredients which may smell different from the original plant. Eugenol extracted from cloves smells of carnations while citral extracted from lemongrass has a scent of violets.
Gas chromatography is used to identify the molecules and the quantities of each molecule that compose an odour, and thus allows the composition to be duplicated.
The most recent modern processes is the headspace technique in which a neutral gas is used to capture the scent-bearing molecules of flowers, such as lilac and lily of the valley, that do not respond well to the above-mentioned methods of extraction. A chromatographic analysis is then carried out so the perfumer can reproduce those molecules.
Not only to these new techniques isolate the components of natural products, but completely new products can be created from those components. More than one thousand new molecules are created each year by chemists who work in the perfume industry, however, only a few are deemed useable by perfume creators. These useable molecules are then patented to guarantee exclusive use for 20 years. After which they become available for general use as it is more profitable to develop new molecules that specifically fulfil immediate needs than it is to extend patents.