| |
|
Perfume is a mixture of fragrant
essential oils and aroma compounds, a fixative, and
alcohol used to give parts of the human body and sometimes
other objects a long-lasting and pleasant smell.
Shelves of perfumesThe essential oils are obtained
by distillation of flowers, plants, and grasses, such
as orange blossom and roses. Extraction by enfleurage
is used if distillation is not possible, for example
in the case of Jasmin Absolute. Enfleurage is basically
extraction by absorption of aroma materials into wax
and then extracting the odorous oil with alcohol.
Aromatic chemicals are also used. 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 amount of alcohol added depends on whether
perfumes, Eaux de toilette, or Eaux de Cologne are
required. The mixture is normally aged for one year.
Perfumes types and properties
As the percentage of aromatic
compounds decreases, the intensity and longevity of
the scent decreases, also.
- Perfume extract: 20%-40%
aromatic compounds
- Eau de parfum: 10-20% aromatic
compounds
- Eau de toilette: 5-10% aromatic
compounds
- Eau de cologne: 2-3% aromatic
compounds
A mixture of alcohol and water
are used as the solvent for the aromatics. On application,
body heat causes the solvent to evaporate quickly,
leaving the fragrance to evaporate gradually over
several hours. The rate of evaporation(vapor pressure)
and the odor strength of the compound partly determines
the tenaciousness of the compound and determines it
perfume note classification.
Top notes: Scents that are
perceived a few minutes after the application of a
perfume. Top notes create the scents that forms 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 wear-down. The heart note compounds form the
"heart" or main body of a perfume and acts
to smooth the sharpness from the initial impression
of perfume that caused by the top notes. Not surprisingly,
the scent of heart note compounds are 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.
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 booster the strength of the lighter
top and heart notes. The compounds of this class of
scents are typically rich and "deep" and
are usally not perceived until 30 minutes after the
application of the perfume or during the period perfume
dry-down. Musk, vetiver and scents of plant resins
are commonly used as base notes.
History of perfume and perfumery
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.
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.
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 herbivory
as well as to attract pollinators. Plants are by far
the largest source of fragrant compounds used in perfumery.
The sources of the these compounds may be derived
from various parts of a plant. A plant will often
be more than one source of aromatics, for instance
coriander aerial portions and seeds have remarkably
different odors from each other. Orange leaves, blossoms,
and fruit zest or the respective sources of petit
grain, neroli oil, and orange oil.
Flowers: Undoubtably the largest
source of aromatics. Includes the flowers of many
species of roses and orchids, as well as jasmine,
osmanthus, mimosa, and tuberose. Although not traditionally
thought of as a flower, the unopened flower buds of
the clove are also a commonly used flower. Orchids
are not commercially used to produce essential oils
or absolutes.
Leaves: Leaves commonly used
for perfumery include patchouli, sage, violets, rosemary,
and citrus leaves. Sometimes leaves are valued for
the "green" smell it brings 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 plant
seeds include coriander, caraway, cocoa, tonka, nutmeg,
mace, cardamom, and anise.
Fruits: Commonly used fruits
include raspberry, strawberry, apple, citrus zests
such as those of oranges, lemons, limes, and grapefruit.
However, fruits do not always impart the expected
"fruity" odors to perfumes. Notable exceptions
include vanilla pods, star anise, pepper, allspice
and durian.
Woods: Highly important in
providing the base notes to a perfume, wood oils and
distillates are indespensible in perfumery. Commonly
used woods include birch, cedar, sandalwood, juniper,
larch, and pine.
Bark: Commonly used bark includes
cinnamon bark.
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, agarwood, and various
copals. 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.
Animal sources
- Musk: Originally derived
from the musk sacs from the Asian musk deer, it
has now been replaced through 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: A fatty substance
obtained from the Sperm Whale.
- Honeycomb: As it name implies,
honey or honeycomb aromatics are distilled from
the honeycomb of the honey bee.
Synthetic sources
Synthetic aromatics are created
through organic synthesis from various chemical compounds
that are obtained from petroleum distillates or pine
resins. 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.
Health and ethical issues
Use of Aromatics
In some cases, an excessive
use of perfumes may cause allergic reactions of the
skin (specifically, acetophenone is a well-known allergen
present in many perfumes).
It is important
to note that there is no benefit from creating a perfume
exclusively from natural materials. There are several
reasons for this:
"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."
It is the policy
of many perfume companies to use synthetic musk in
place of natural musk for ethical reasons. Many synthetic
musks are available and those used are all approved
safe by IFRA.
|
