- For the book "Perfume" by Patrick Süskind, see Perfume (book).
Perfume is a mixture of fragrant essential oils and aroma compounds, fixatives, and solvents used to give the human body, objects, and living spaces a lasting and pleasant smell. The amount and type of solvent mix with the fragrance oil dictates whether a perfume is considered a perfume extract, Eau de parfum, Eau de toilette, or Eau de Cologne.
Bottles of some well known perfumes
Obtaining odorants
Before perfumes can be composed, the odorants used in various perfume compositions must first be obtained. Synthetic odorants are produced through organic synthesis and purified. Odorants from natural sources require the use of various methods to extract the aromatics from the raw materials. The results of the extraction are either essential oils, absolutes, concretes, or butters, depending on the amount of waxes in the extracted product.
All these techniques will to a certain extent, distort the odour of the aromatic compounds obtained from the raw materials. This is due to the use of heat, harsh solvents, or through exposure to oxygen in the extraction process which will denature the aromatic compounds, which either change their odour character or renders them odourless.
- Maceration/Solvent extraction: The most commonly used and economically important technique for extracting aromatics in the modern perfume industry. Raw materials are submerged in a solvent that can dissolve the desired aromatic compounds. Maceration lasts anywhere from hours to months. Fragrant compounds for woody and fibrous plant materials are often obtained in this matter as are all aromatics from animal sources. The technique can also be used to extract odorants that are too volatile for distillation or easily denatured by heat. Commonly used solvents for maceration/solvent extraction include hexane, and dimethyl ether. The product of this process is call a "concrete".
- Supercritical fluid extraction: A relatively new technique for extracting fragrant compounds from a raw material, which often employ supercritical CO2. Due to the low heat of process and the relatively unreactive solvent used in the extraction, the fragrant compounds derived often closely resemble the original odour of the raw material.
- Ethanol extraction: A type of solvent extraction used to extract fragrant compounds directly from dry raw materials, as well as the impure oily compounds materials resulting from solvent extraction or enfluerage. Ethanol extraction is not used to extract fragrace from fresh plant materials since these contain large quantities of water, which will also be extracted into the ethanol.
- Distillation: A common technique for obtaining aromatic compounds from plants, such as orange blossoms and roses. The raw material is heated and the fragrant compounds are re-collected through condensation of the distilled vapour.
- Steam distillation: Steam from boiling water is passed through the raw material, which drives out their volatile fragrant compounds. The condensate from distillation are settled in a Florentine flask. This allows for the easy separation of the fragrant oils from the water. The water collected from the condensate, which retains some of the fragrant compounds and oils from the raw material is called hydrosol and sometimes sold. This is most commonly used for fresh plant materials such as flowers, leaves, and stems.
- Dry/destructive distillation: The raw materials are directly heated in a still without a carrier solvent such as water. Fragrant compounds that are released from the raw material by the high heat often undergo anhydrous pyrolysis, which results in the formation of different fragrant compounds, and thus different fragrant notes. This method is used to obtain fragrant compounds from fossil amber and fragrant woods where an intentional "burned" or "toasted" odour is desired.
- Expression: Raw material is squeezed or compressed and the oils are collected. Of all raw materials, only the fragrant oils from the peels of fruits in the citrus family are extracted in this manner since the oil is present in large enough quantities as to make this extraction method economically feasible.
- Enfleurage: Absorption of aroma materials into wax and then extracting the odorous oil with alcohol. Extraction by enfleurage was commonly used when distillation was not possible due to the fact that some fragrant compounds denature through high heat. This technique is not commonly used in the present day industry due to its prohibitive cost and the existence of more efficient and effective extraction methods.
Fragrant extracts
Although fragrant extracts are known to the general public as the generic term "essential oils", a more specific language is used in the fragrance industry to describe the source, purity, and technique used to obtain a particular fragrant extract.
Of these extracts, only absolutes, essential oils, and tinctures are directly used to formulate perfumes.
- Absolute: Fragrant materials that are purified from a pommade or concrete by soaking them in ethanol. By using a slightly hydrophilic compound such as ethanol, most of the fragrant compounds from the waxy source materials can be extracted without dissolving any of the fragrantless waxy molecules. Usually in the form of an oily liquid.
- Concrete: Fragrant materials that have been extracted from raw materials through solvent extraction using volatile hydrocarbons. Concretes usually contain a large amount of wax due to the ease in which the solvents dissolve various hydrophobic compounds. As such concretes are usually further purified through distillation or ethanol based solvent extraction. Usually in the form of an waxy or resinous solid.
- Essential oil: Fragrant materials that have been extracted from a source material directly through distillation or expression. Usually in the form of an oily liquid. Oils extracted through expression are sometimes called expression oils.
- Pommade: A fragrant mass of solid fat created from the enfleurage process, in which odorous compounds in raw materials are adsorbed into animal fats. Usually in the form of an oily and sticky solid.
- Tincture: Fragrant materials produced by directly soaking and infusing raw materials in ethanol. Usually in the form of a thin liquid.
Composing perfumes
Perfume oils usually contain tens to hundreds of ingredients. Included in the perfume are fixatives, which bind the various fragrances together, include balsams, ambergris, and secretions from the scent glands of civets and musk deer (undiluted, these have unpleasant smells but in alcoholic solution they act as preserving agents). The mixture is normally aged for one year.
Description of a perfume
It is impossible to describe a perfume according to its components because the exact formulas are kept secret. Even if the formulas are known, the ingredients are often too numerous to provide a useful classification. On the other hand, it is possible to group perfumes into olfactive families and describe them through the notes that appear as they slowly evaporate. Perfumes can also be classified according to their concentration.
Olfactive families
Traditionally, fragrances that are clasified in seven olfactive families, whose names may vary:
- Floral: Fragrances that are dominated by the scent of one or more types of flowers. When only one flower is used, it is called a soliflore (as in Dior's Diorissimo, with jasmine).
- Chypre: Fragrances build on a similar base consisting of bergamot, jasmine and oakmoss. This family of fragrances is named after a perfume by François Coty by the same name. Meaning Cyprus in French, the term alludes to where this base was inspired. This fragrance family is characterized by a scent reminiscent of apricot and custard.
- Fougère: Fragrances built on a base of lavender, coumarin and oakmoss. Many men's fragrances belong to this family of fragrances, which is characterized by its sharp herbaceous and woody scent.
- Leather: A family of fragrances which features the scents honey, tobacco, wood, and wood tars in its middle or base notes and a scent that alludes to leather.
- Woody: Fragrances that are dominated by the woody scents, typically of sandalwood and cedar. Patchouli, with in camphorous smell is also used in this fragrance family.
- Orientals or ambers: A large fragrance class featuring the scents of vanilla and animal scents together with flowers and woods. Typically enhanced by camphorous oils and incense resins, which bring to mind Victorian era imagery of the East and Far East.
- Citrus: An old fragrance family that until recently consisted mainly of "freshening" Eau de colognes due to the low tenacity of citrus scents. Development of newer fragrance compounds has allowed for the creation of primarily citrus fragrances.
Fragrance Notes
A mixture of alcohol and water is used as the solvent for the aromatics. On application, body heat causes the solvent to quickly disperse, leaving the fragrance to evaporate gradually over several hours. The rate of evaporation (vapor pressure) and the odor strength of the compound partly determine the tenaciousness of the compound and determine its perfume note classification.
- Top notes: Scents that are perceived a few minutes after the application of a perfume. Top notes create the scents that form a person's initial impression of a perfume. Because of this, they are very important in the selling of a perfume. The scents of this note class are usually described as "fresh," "assertive" or "sharp." The compounds that contribute to top notes are strong in scent, very volatile, and evaporate quickly. Citrus and ginger scents are common top notes.
- Heart notes or Middle notes: The scent of a perfume that emerges after the top notes dissipate. The heart note compounds form the "heart" or main body of a perfume and act to smooth the sharpness from the initial impression of a perfume caused by the top notes. Not surprisingly, the scent of heart note compounds is usually more mellow and "rounded." Scents from this note class appear anywhere from 10 minutes to 1 hour after the application of a perfume. Lavender and rose scents are typical heart notes. Top notes and heart notes are sometimes described together as Head notes.
- Base notes: The scent of a perfume that appears after the departure of the heart notes. Base notes bring depth and solidness to a perfume. Compounds of this class are usually the fixatives used to hold and boost the strength of the lighter top and heart notes. The compounds of this class of scents are typically rich and "deep" and are usually not perceived until 30 minutes after the application of the perfume or during the period of perfume dry-down. Musk, vetiver and scents of plant resins are commonly used as base notes.
Concentration
Perfumes oils, or the "juice" of a perfume composition, are diluted with a suitable solvent to make the perfume more usable. This is done because undiluted oils contain volatile components that would be too concentrated for people with sensitive skin or allergies. Although dilutions of the perfume oil can be done using solvents such as jojoba, fractionated coconut oil, and wax, the most common solvents for perfume oil dilution is ethanol or a mixture of ethanol and water. The percent of perfume oil by volume in a perfume is listed as follows:
- Perfume extract: 20%-40% aromatic compounds
- Eau de parfum: 10-30% aromatic compounds
- Eau de toilette: 5-20% aromatic compounds
- Eau de cologne: 2-3% aromatic compounds
As the percentage of aromatic compounds decreases, the intensity and longevity of the scent decrease. It should be noted that different perfumeries or perfume houses assign different amounts of oils to each of their perfumes. As such, although the oil concentration of a perfume in eau de parfum dilution will necessarily be higher than the same perfume in eau de toilette form, the same trends may not necessarily apply to different perfume compositions much less across different perfume houses.
History of perfume and perfumery
Egyptian scene depicting the preparation of Lily perfume
Perfumery, or the art of making perfumes, began in ancient Egypt but was developed and further refined by the Romans and the Arabs. Knowledge of perfumery came to Europe as early as the 14th century. During the Renaissance period, perfumes were used primarily by royalty and the wealthy to mask bodily odors resulting from the sanitary practices of the day.
In the Islamic culture, perfume usage has been documented as far back as the 6th century and its usage is considered a religious duty. The Prophet Muhammad said, "The taking of a bath on Friday is compulsory for every male Muslim who has attained the age of puberty and (also) the cleaning of his teeth with Siwak (type of twig used as a toothbrush), and the using of perfume if it is available." (Recorded in Sahih Bukhari)
Partly due to this patronage, the western perfumery industry was created. By the 18th century, aromatic plants were being grown in the Grasse region of France to provide the growing perfume industry with raw materials. Even today, France remains the centre of the European perfume design and trade.
Perfumers were also known to create poisons; for instance, a French duchess was murdered when a perfume/poison was rubbed into her gloves and was, thus, slowly absorbed into her skin.
Famous perfumes classified by year of creation
Natural and synthetic aromatics
Plant sources
Plants have long been used in perfumery as a source of essential oils and aroma compounds. These aromatics are usually secondary metabolites produced by plants as protection against herbivores as well as to attract pollinators. Plants are by far the largest source of fragrant compounds used in perfumery. The sources of these compounds may be derived from various parts of a plant. A plant can offer more than one source of aromatics, for instance the aerial portions and seeds of coriander have remarkably different odors from each other. Orange leaves, blossoms, and fruit zest are the respective sources of petit grain, neroli, and orange oils.
- Flowers and Blossoms: Undoubtably the largest source of aromatics. Includes the flowers of several species of rose and lavender, as well as jasmine, osmanthus, mimosa, tuberose, as well as the blossoms of citrus and ylang-ylang trees. Although not traditionally thought of as a flower, the unopened flower buds of the clove are also commonly used. Orchid flowers are not commercially used to produce essential oils or absolutes.
- Leaves and Twigs: Commonly used for perfumery are patchouli, sage, violets, rosemary, and citrus leaves. Sometimes leaves are valued for the "green" smell they bring to perfumes, examples of this include hay and tomato leaf.
- Roots, rhizomes and bulbs: Commonly used terrestrial portions in perfumery include iris rhizomes, vetiver roots, various rhizomes of the ginger family.
- Seeds: Commonly used seeds include tonka bean, coriander, caraway, cocoa, nutmeg, mace, cardamom, and anise.
- Fruits: Fresh fruits such as apples, strawberries, cherries unfortunately do not yield the expected odors; if you find such fragrance notes in a perfume, they're synthetic. Notable exceptions include litsea cubeba, vanilla, and juniper berry. The most commonly used fruits yield their aromatics from the rind; they include citrus such as oranges, lemons, limes, and grapefruit.
- Woods: Highly important in providing the base notes to a perfume, wood oils and distillates are indispensible in perfumery. Commonly used woods include sandalwood, rosewood, agarwood, birch, cedar, juniper, and pine.
- Bark: Commonly used barks includes cinnamon and cascarilla. The fragrant oil in sassafras root bark is also used either directly or purified for its main constituent, safrole, which is used in the synthesis of other fragrant compounds such as helional.
- Resins: Valued since antiquity, resins have been widely used in incense and perfumery. Highly fragrant and antiseptic resins and resin-containing perfumes have been used by many cultures as medicines for a large variety of ailments. Commonly used resins in perfumery include labdanum, frankincense/olibanum, myrrh, Peru balsam, gum benzoin. Pine and fir resins are a particularly valued source of terpenes used in the organic synthesis of many other synthetic or naturally occurring aromatic compounds. Some of what is called amber and copal in perfumery today is the resinous secretion of fossil conifers.
- Lichens: Commonly used lichen includes oakmoss and treemoss thalli.
Animal sources
- Musk: Originally derived from the musk sacs from the Asian musk deer, it has now been replaced by the use of synthetic musks due to its price and various ethical issues.
- Civet: Also call Civet Musk, this is obtained from the odorous sacs of the civets, animals in the family Viverridae, related to the Mongoose.
- Castoreum: Obtained from the odorous sacs of the North American beaver.
- Ambergris: Lumps of oxidized fatty compounds, whose precursors were secreted and expelled by the Sperm Whale. Ambergris is commonly referred as "amber" in perfumery and should not be confused with yellow amber, which is used in jewelry.
- Honeycomb: Distilled from the honeycomb of the Honeybee.
Synthetic sources
Synthetic aromatics are created through organic synthesis from various chemical compounds that are obtained from petroleum distillates, pine resins, or other relatively cheap organic feedstock. Synthetics can provide fragrances which are not found in nature. For instance, Calone, a compound of synthetic origin, imparts a fresh ozonous metallic marine scent that is widely used in contemporary perfumes. Synthetic aromatics are often used as an alternate source of compounds that are not easily obtained from natural sources. For example, linalool and coumarin are both naturally occurring compounds that can be cheaply synthesized from terpenes. Orchid scents are usually not obtained directly from the plant itself but are instead synthetically created to match the fragrant compounds found in various orchids.
The majority of the world's synthetic aromatics are created by relatively few companies. They include:
Each of these companies patent several processes for the production of aromatic synthetics annually.
See Aroma compound
Health and ethical issues
Use of Aromatics
In some cases, an excessive use of perfumes may cause allergic reactions of the skin. For instance, acetophenone, ethyl acetate and acetone while present in many perfumes, are also known or potential respiratory allergens.
It is important to note that there is no benefit from creating a perfume exclusively from natural materials. There are several reasons for this:
- Many natural aroma materials are in fact inherently toxic and are either banned or restricted by IFRA. These naturals have been replaced by safer artificial or synthetic materials.
- Many natural materials and essential oil contain the same chemicals used in perfumes that are classified as allergens, many of them at higher concentrations.
- Perfume composed only of expensive natural materials could be very expensive. Synthetic aromatics make possible perfumes at reasonable prices.
- In the distillation of natural essential oils any biocides (including pesticides, herbicides, or fungicides) that have been applied while the plant is growing may be concentrated into the essential oil making the oil toxic. Unless the essential oil is distilled from a certified organic origin, it may be dangerous.
- There are many new synthetic aromas that bear no olfactory relationship to any natural material and yet modern perfumery depends on these new odours for the infinite variety of perfumes available today. Many synthetics have very beautiful aromas not available in nature.
Natural Musk
Musk was traditionally taken from the male musk deer Moschus moschiferus. This requires the killing of the animal in the process. Although the musk pod is produced only by a young male deer in oestrus musk hunters usually did not discriminate between the age and sex of the deers. Due to the high demand of musk and indiscriminate hunting, populations were severely depleted. As a result, the deer is now protected by law and international trade of musk from Moschus moschiferus is prohibited:
"Musk deer are protected under national legislation in many countries where they are found. The musk deer populations of Afghanistan, Bhutan, India, Nepal and Pakistan are included in Appendix I of CITES, the Convention on International Trade in Endangered Species of Wild Fauna and Flora. This means that these musk deer and their derivatives are banned from international commercial trade." [1]
Due to its legality, rarity, high price, and ethical reasons, it is the policy of many perfume companies to use synthetic musk in place of natural musk for ethical reasons. Numerous synthetic musks of high quality are readily available. approved safe by IFRA.
Celebrity Endorsed Perfumes
In recent trends, celebrities whom wish to earn money, or market themselves, associate themselves with contracts that put their name with a signature scent. The scents are then heavily marketed; and with the celebrity's name often being the pinnicle of the campaign, and also the factor in the attraction of customers.
Celebrity Scents:
See also
Reference
- Arcadi Boix Camps. (2000). "Perfumery Techniques in Evolution". Allured Pub Corp. ISBN 0931710723
- Anne-Dominique Fortineau. (2004). "Chemistry Perfumes Your Daily Life". Journal of Chemical Education.81(1)
External links
- Biblioparfum An impressive personal collection of more than 600 books about perfume (mostly French)
- Fabulous Fragrances An educational perfume portal with information on perfume usage, fragrance classifications, and history. Includes books by Jan Moran (Fabulous Fragrances II) and Michael Edwards (Fragrances of the World), as well as online programs, a forum, and a Q & A column, Scents of Style, where readers can ask questions.
- A guide to natural fragrances A site with information regarding various fragrant plants used in perfumery and their active chemical odorants. Images of both plant and odorant structure.
- The sense of smell. Educational site with information regarding the sense of smell, the process of fragrance evaluation, and a bit on organic synthesis of fragrance chemicals.
- osMoz Overview of the perfume and cologne making process, fragrance classifications, and a directory of leading perfumers.