Perfume is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Perfumes can be defined as substances that emit and diffuse a pleasant and fragrant odor. They consist of manmade mixtures of aromatic chemicals and essential oils. The 1939 Nobel Laureate for Chemistry, Leopold Ružička stated in 1945 that "right from the earliest days of scientific chemistry up to the present time, perfumes have substantially contributed to the development of organic chemistry as regards methods, systematic classification, and theory."
Terpenes are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. In plants, terpenes and terpenoids are important mediators of ecological interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control.
Linalool refers to two enantiomers of a naturally occurring terpene alcohol found in many flowers and spice plants. Together with geraniol, nerol, citronellol, linalool is one of the rose alcohols. Linalool has multiple commercial applications, the majority of which are based on its pleasant scent.
Fragrance oils, also known as aroma oils, aromatic oils, and flavor oils, are blended synthetic aroma compounds or natural essential oils that are diluted with a carrier like propylene glycol, vegetable oil, or mineral oil.
Neroli oil is an essential oil produced from the blossom of the bitter orange tree. Its scent is sweet, honeyed and somewhat metallic with green and spicy facets. Orange blossom is also extracted from the same blossom and both extracts are extensively used in perfumery. Orange blossom can be described as smelling sweeter, warmer and more floral than neroli. The difference between how neroli and orange blossom smell and why they are referred to with different names, is a result of the process of extraction that is used to obtain the oil from the blooms. Neroli is extracted by steam distillation and orange blossom is extracted via a process of enfleurage or solvent extraction.
Citronellol, or dihydrogeraniol, is a natural acyclic monoterpenoid. Both enantiomers occur in nature. (+)-Citronellol, which is found in citronella oils, including Cymbopogon nardus (50%), is the more common isomer. (−)-Citronellol is widespread, but particularly abundant in the oils of rose (18–55%) and Pelargonium geraniums.
Camphene is a bicyclic organic compound. It is one of the most pervasive monoterpenes. As with other terpenes, it is insoluble in water, flammable, colorless, and has a pungent smell. It is a minor constituent of many essential oils such as turpentine, cypress oil, camphor oil, citronella oil, neroli, ginger oil, valerian, and mango. It is produced industrially by isomerization of the more common alpha-pinene using a solid acid catalyst such as titanium dioxide.
Nerolidol, also known as peruviol and penetrol, is a naturally occurring sesquiterpene alcohol. A colorless liquid, it is found in the essential oils of many types of plants and flowers. There are four isomers of nerolidol', which differ in the geometry about the central double bond and configuration of the hydroxyl-bearing carbon, but most applications use such a mixture. The aroma of nerolidol is woody and reminiscent of fresh bark. It is used as a flavoring agent and in perfumery as well as in non-cosmetic products such as detergents and cleansers. Nerolidyl derivatives include nerolidyl diphosphate and the fragrance nerolidyl acetate.
Farnesyl pyrophosphate (FPP), also known as farnesyl diphosphate (FDP), is the precursor to all sesquiterpenes, which comprises thousand of compounds. These include all sesquiterpenes as well as sterols and carotenoids. It is also used in the synthesis of CoQ, as well as dehydrodolichol diphosphate.
Geranyl acetate is a terpenoid. It is a colorless liquid with a pleasant floral or fruity rose aroma. It is a colorless liquid but commercial samples can appear yellowish. Geranyl acetate is insoluble in water but soluble in organic solvents. Several hundred tons are produced annually.
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. It is estimated (2006) that 3000 sesquiterpenes have been identified.
Monoterpenes are a class of terpenes that consist of two isoprene units and have the molecular formula C10H16. Monoterpenes may be linear (acyclic) or contain rings (monocyclic and bicyclic). Modified terpenes, such as those containing oxygen functionality or missing a methyl group, are called monoterpenoids. Monoterpenes and monoterpenoids are diverse. They have relevance to the pharmaceutical, cosmetic, agricultural, and food industries.
Phenethyl alcohol, or 2-phenylethanol, is an organic compound with the chemical formula C6H5CH2CH2OH. It is a colourless liquid with a pleasant floral odor. It occurs widely in nature, being found in a variety of essential oils. It is slightly soluble in water, but miscible with most organic solvents. The molecule of phenethyl alcohol consists of a phenethyl group attached to a hydroxyl group.
Undecylenic acid is an organic compound with the formula CH2=CH(CH2)8CO2H. It is an unsaturated fatty acid. It is a colorless oil. Undecylenic acid is mainly used for the production of Nylon-11 and in the treatment of fungal infections of the skin, but it is also a precursor in the manufacture of many pharmaceuticals, personal hygiene products, cosmetics, and perfumes. Salts and esters of undecylenic acid are known as undecylenates.
Eau de toilette is a lightly scented perfume. It is also referred to as aromatic waters and has a high alcohol content. It is usually applied directly to the skin after bathing or shaving. It is traditionally composed of alcohol and various volatile oils. Traditionally these products were named after a principal ingredient, like geranium water, lavender water, lilac water, violet water, spirit of myrcia and "eau de Bretfeld". Because of this, eau de toilette was sometimes referred to as "toilet water".
Benzyl salicylate is a salicylic acid benzyl ester, a chemical compound most frequently used in cosmetics as a fragrance additive or UV light absorber. It appears as an almost colorless liquid with a mild odor described as "very faint, sweet-floral, slightly balsamic" by some, while others smell nothing at all. There is debate whether the odour is caused solely by impurities or a genetic predisposition. It occurs naturally in a variety of plants and plant extracts and is widely used in blends of fragrance materials.
Linalyl acetate is an organic compound, the acetate ester of linalool and a phytochemical found in many flowers and spice plants. It is one of the principal components of the essential oils of bergamot and lavender. It often occurs together with linalool and is a widely used fragrance.
Rosefuran (3-methyl-2-prenylfuran) is an organic compound, classified as a terpenoid. It is a minor constituent of the aroma of the rose. Rosefuran is a 2,3-disubstituted furan. It has an odor threshold of 200 ppb and constitutes 0.16% of Bulgarian rose oil. Rosefuran has been established as a female sex pheromone of an acarid mite, Caloglyphus sp. Concentrations of less than 100 ng of synthetic rosefuran caused sexual excitation in males of the species.
Neryl acetate is a terpenoid found in citrus oils. It is the acetate ester of nerol, an isomer of the more common fragrance geranyl acetate. In flavors and perfumery it is used to impart floral and fruity aromas.
