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Introduction Essential oils, or volatile oils, are found in many
different plants. These oils are
different from fatty oils because they evaporate or volatilize on contact
with the air and they possess a pleasant taste and strong aromatic odor. They are readily removed from plant
tissues without any change in composition.
Essential oils are very complex in their chemical nature. The two main groups are the hydrocarbon
terpenes and the oxygenated and sulphured oils. These oils do not have any obvious
physiological significance for the plant.
They may represent byproducts or metabolism rather than foods. The characteristic flavor and aroma that
they impart are probably to some advantage in attracting insects and other
animals, which play a role in pollination or in the dispersal of the fruits and
seeds. When in high concentration,
these same odors may serve to repel enemies of the plants. The oils may also have some antiseptic and
bactericidal value. There is some
evidence that they play an even more vital role as hydrogen donors in
oxidoreduction reactions, as potential sources of energy, or in affecting
transpiration and other physiological processes (Hill 1952). All the distinctly aromatic plants
contain essential oils. They occur in
over 60 families and are especially typical of the Lauraceae,
Myrtaceae, Umbelliferae, Labiatae and Compositae. The quantity of oil varies from a very
small amount to as much as 1-2 percent.
The oils are secreted by internal glands or in hair like structures. Sometimes, as in wintergreen and mustard,
the oil is not present in the plant but develops only as the result of
chemical action when the ground-up plant tissue is extracted with water. Almost any organ of a plant may be the
source of the oil. Examples are
flowers (rose), leaves (mint), fruits (lemon), bark (cinnamon), wood (cedar),
root (ginger) or seeds (cardamom), and many resinous exudations as well. These oils are extracted from the
plant tissues in different ways depending on the quantity and stability of
the compound. Three principal methods
are: expression, distillation and
extraction by solvents. The history of civilization is
directly connected with that of perfumes.
Perfumes have been in widespread use since the earliest recorded
times. The Egyptians and ancient
Hebrews used them for both personal and religious purposes. They played an important role in the life
of the Romans and Greeks, reaching such a high degree of specialization with
the Greeks that a special perfume was required for each part of the
body. Later Catherine de’ Medici knew
as much about perfumes as she did about poisons. In the time of Queen Elizabeth a gift of rare perfumes was a
definite way to win the royal favor, while the court of Louis XIV at
Versailles had a particular perfume for each day of the year, the preparation
of which was supervised by the king himself.
In those days perfumes were of hygienic as well as aesthetic value for
they acted as true antiseptics and deodorants and masked offensive odors at a
time when bathing was infrequent.
Perfumes have continued to be in great demand to the present day. The consumption of the natural products
has gradually increased in spite of the many synthetic substitutes that
chemists have placed on the market.
Synthetics are not as long lasting as those obtained directly from the
plants. The most valuable perfumes are
combinations of several essential oils.
Frangipani, for example, contains sandalwood, sage, neroli, orris
root, and musk, while one of the formulas for Eau de Cologne, which
dates from 1709, calls for neroli, rosemary, lemon and bergamot dissolved in
pure alcohol and aged. “The expert
perfumer must be able to blend the several oils at his command as an
orchestra leader combines the various instruments into a perfect whole” (Hill
1952). Perfumes also contain fixatives,
which are substances that are less volatile than the oils and which delay and
so equalize evaporation. These may be
of plant or animal origin. Musk,
ambergris, and civet are frequently used for this purpose. Balsams and oleoresins, such as benzoin,
styrax, and oak moss; essential oils with a low rate of evaporation like
orris, patchouli, elary sage, and sandalwood; and various synthetic materials
are also used. Perfume plants are cultivated for
the most part in areas bordering on the Mediterranean Sea and the Indian
Ocean. Most of the natural perfumes
are made in southern France in the region around Grasse and Cannes near the
French Riviera. Here garden flowers
are cultivated on a large scale, and from 10-12 billion pounds were being
gathered annually by the mid 1950’s.
These included over 5 million pounds of orange blossoms, over 4
million pounds of roses, 440 thousand pounds of jasmine and 330 thousand
pounds of violets. Large quantities
of tuberoses, cassie, jonquils, thyme, rosemary, lavender and geraniums are
grown and many other fragrant species to a lesser degree. Flowers are also grown for the perfume
industry to some extent in Reunion, North Africa, England and various
European, Pacific and Asiatic areas.
When supplies were reduced during World War II, the United States
developed substitutes and initiated or increased the cultivation of several
essential oil plants in Central America.
Of the 75 essential oils regularly used in the industry only eight are
normally produced in the Western Hemisphere, and only oil of petitgrain is of
much importance. Some of
the more important essential oils used in the manufacture of perfumes are as
follows: <bot808> Apricot (Prunus armeniaca
L.) (fruit; perfumes; medicines)
[Manchuria] This is valuable oil that is also
called Attar
of Roses. It has been one of the most favorite
perfumes either in combination with other oils or alone. Bulgaria supplied most the commercial supply
in the 20th Century. The Damask
rose, Rosa damascena,
was the main source. By the mid
1900’s over 12,000 acres on the southern slopes of the Balkans were devoted
to its cultivation. The harvest
period covers about three weeks during May-June. Flowers are picked in the early morning just as they are
opening and are distilled immediately.
In the beginning of this industry peasant farmers utilized their own
primitive stills, but this gave way to larger modern distilleries. The oil is colorless at first but
gradually turns a yellowish or greenish color. More than 20,000 lbs of the flowers are required to make one
pound of the essence, which was valued at $200.00 in 1952. Very little pure Otto reaches the markets
because it is almost always diluted with geranium or palmarosa oil or
geraniol, which also have a rose like odor.
Otto of Roses is also manufactured in France, Italy, North Africa,
Asia Minor and India. In France the Cabbage
rose, R. centifolia
was used and the perfume was obtained both by hot and cold enfleurage as well
as by distillation. Large quantities
of rose water are also made. This
consists mainly of the water left after distillation, which still contains
some of the essence. Dissolving a
small amount of Otto in water sometimes makes it. Pelargonium
spp. leaves yield an
essential oil after distillation.
Geranium oil is widely used as an adulterant of or a substitute for
Otto of Roses in making perfumes and soap.
Pelargonium graveolens is most frequently
grown especially in Algeria and Reunion and to a lesser extent in southern
France and Spain. Cultural
experiments have been made in Florida, Texas and California with P. odoratissimum, the rose
geranium. The plants are easy to
propagate from slips and are productive for 5-6 years after reaching
maturity. They must be grown in
minimum frost areas. A good grade of
oil is obtained from the leaves of this species. A very valuable oil in the perfume
industry, it is added to almost every perfume. The name translates as “flower of flowers.” The ylang-ylang
tree is an Eastern Asiatic species, Canaya odorata. Its yellowish-green, bell shaped flowers
have an exceedingly delicate and evanescent fragrance. The oil is also known as Canaga Oil and is derived by simple
distillation or extraction from the petals of fully opened blossoms. Most production was originally in The
Philippines, but later French colonies in the Indian Ocean dominated the
cultivation. This tree grows wild or
cultivated in various parts of Southern Asia and the East Indies. The oil first arrived in Europe around
1864 and since that time it has been in great demand despite its high cost. Flowers of the Sweet
acacia, Acacia farnesiana,
yield an essential oil that is almost as valuable as Ylang-Ylang or Otto of
Roses. It is a thorny small tree of
the West Indies, but has spread to many tropical and subtropical areas. It is extensively cultivated in southern
France, Algeria, Egypt, Syria and India as a source of perfume. The oil is removed from the petals by
maceration with cocoa butter or coconut oil, or by extraction. It is similar to the odor of violets and
is widely used for sachets, powders and pomades. This oil, obtained from orange
blossoms, is extensively used in blends and for mixing with synthetic
perfumes. True oil of Neroli, or
Neroli Bigarade, is distilled from flowers of the Bitter
orange, Citrus aurantium. Neroli Portugal is from the Sweet
orange, Citrus sinensis. Leading production has been in southern
France, surrounding Mediterranean areas and in the West Indies, particularly
in Haiti. Other essential oils are also derived
from Oranges and used in making perfumes.
The leaves and twigs and sometimes immature fruits, supply Petitgrain
Oil. This adds a pleasant bouquet to
scents, cosmetics and soap. Paraguay
has been the main producer. Bitter or
sweet oranges are used and the oil is extracted by distillation. Oil of Orange is obtained by expressing
the ripe orange peel, but it results in an inferior grade. This is greenish oil that is expressed
from the rind of the Bergamot
(Citrus aurantium subsp. bergamia). It has a soft sweet odor and has been
widely used in the United States for adding scent to toilet soaps and in
mixed perfumes. Italy and Sicily have
been the chief exporters. Rhizomes of Iris pallida, I. florentina
and allied species contain an essential oil
that has the odor of violets.
Tincture of Orrisroot has been used to adulterate pure extract of
violets and the powdered root is the basis of violet powder. Cultivation is in Southern Europe, Iran
and northern India. Italian orrisroot
is superior to other sources. The
rhizomes are peeled and dried in the sun, and the odor gradually
develops. Orris is also used as a
flavoring substance. The roots of Calamus are the sweet
and aromatic rhizomes of the Sweet flag, Acorus calamus. It is a common plant of marshy ground in
Europe, Asia and America. In powdered
form Calamus is used for sachet and toilet powders, while the distilled oil
is used in making perfumes. It has
also been used for medicinal and flavoring purposes. The candied root was once a popular
confection. Several important essential oils
are derived from grasses and used in the perfume industry. The genus Cymbopogon
(formerly Andropogon)
is especially rich in perfume species.
The oil is
distilled from the leaves of Cymbopogon nardus. Java and Sri-Lanka have produced most of
the world supply. The pale-yellow oil
is inexpensive and used for making soaps and perfumes and as an insect
repellent. The oil contains 80-90
percent geraniol, and is therefore an important substitute for Otto of
Roses. Citronella was also introduced
into Central America where a considerable industry developed in Guatemala and
Honduras with over 4,500 acres under cultivation by 1952. The crop is harvested by hand. Cutting stimulates growth and a new crop
is available in three months. The oil
is extracted by steam distillation. Leaves of Cymbopogon citratus yield
reddish-yellow oil with a strong odor and taste of lemons upon
distillation. There is a very high
content of citral in the leaves (70-80%).
It is used in soaps and medicine.
Citral is extensively used in perfumes, bath salts, cosmetics and
toilet soaps and as a food flavoring.
It is also the source of the aromatic substances known as ionones,
which have many uses. One of the
ionones is required in the synthesis of Vitamin A; another is the raw
material for synthetic violet. Lemon grass is common in the
eastern tropics and is cultivated in Sri-Lanka, East Africa, India, the Congo
and Madagascar. It was successfully
introduced in the Western Hemisphere where large quantities of the oil were
exported from Haiti, Brazil, Guatemala, El Salvador and other Neotropical
areas. Palmarosa / Ginger-grass Oils These are nearly identical oils that
have been used as adulterants of Otto of Roses. They contain a high amount of Geraniol. Cymbopogon
martinii and
related species are cultivated in India as a source and have been exported in
large quantities. The roots and rhizomes of the Khuskhus
plant, Vetiveria zizanioides,
supply this oil. It is a native of
Bengal and India, but has been grown throughout the tropics and
subtropics. The roots have a very
sweet scent and are made into mats, fans, screens, awnings, sunshades,
baskets, sachet bags and pillows. The
leaves are odorless. The plant was
introduced into the West Indies and Louisiana and is widely used as an
ornamental plant. It has escaped
cultivation and become naturalized in many areas. On distillation the roots yield oil that is similar to
citronella and which has been used for making expensive perfumes, soaps and
in medicine. It is one of the best
fixatives. Leaves of Pimenta racemosa yield
oil on distillation, which is used in perfumery and in the preparation of bay
rum. The plant is native to the West
Indies where the industry is located.
Originally the leaves were distilled in rum and water, but now the oil
is dissolved in alcohol and various aromatic substances are mixed in. Bay rum has soothing and antiseptic
properties. Lavender perfumes are very old and
were used by the Romans in their baths.
It is still one of the most important scents. The True
lavender plant, Lavandula officinalis,
is native to Southern Europe, where it occurs on dry, barren soil. It is a low shrub with terminal spikes of
very fragrant bluish flowers. There
are many horticultural forms and hybrids occur. Lavender is grown in southern France at altitudes of 1500-1800
ft. Large amounts are also raised in
England. Lavender has a clean odor
and the dried flowers are used in sachets and for scenting chests and
drawers. The oil is important in the
manufacture of Eau de Cologne and other perfumes and is also used in soaps,
cosmetics and medicine as a mild stimulant.
Lavender water, a mixture of the oil in water and alcohol, is popular
in England (Yardley brand). <bot461> Wild Lavender (Lavandula officinalis Chaix.) [S. Europe], north coast Jamaica This lavender, Lavandula latifolia, is coarser and
yields an inferior grade of oil. It
can be grown at lower altitudes than true lavender and is extensively
cultivated in France and Spain. It is
used in perfumes and cosmetics and to flavor meat sauces known as aspic. One of the most popular perfumes
is made from violets. Blue and pur0le
double varieties of Viola odorata,
native to Europe, are grown mainly in the vicinity of Nice. Solvents or
maceration with hot fats extracts the oil.
It occurs in such minute amounts that 15 tons of flowers are required
to obtain only one pound of oil.
Genuine violet perfume is rare and expensive, and it has been almost
entirely replaced by synthetic products derived from ionone. A highly esteemed perfume, Jasmine
is cultivated in southern France and surrounding areas. The main source is Jasminum officinarum var. grandiflorum,
which is usually grafted on a less desirable variety. The flowers are picked as soon as they are
open and the oil is extracted by enfleurage. There are thousands of
horticultural varieties of carnation all derived from Dianthus caryophyllus, a species of
southern Europe, Northern Africa and tropical Asia. The most conspicuous blossoms and color give the least
odor. Therefore, for the perfume
industry varieties with less conspicuous blossoms are used. Solvents extract the oil. Synthetic carnation oil predominates in
world markets. Rosemary, Rosmarinus officinalis, is a native of
the Mediterranean region. It has long
been a favored sweet-scented plant and has been important in the folklore of
many countries. It is one of the
least expensive and most refreshing odors.
The plant is a small evergreen shrub that is cultivated in Europe and
the United States. The oil is
extracted by distillation of the leaves and fresh flowering tops or by
extraction. It is used in Eau de
Cologne, toilet soap and medicine.
The leaves are valuable as a spice. Hyacinthus
orientalis is
native to Western Asia and Asia Minor.
It was introduced into Europe in the 16th Century where it was grown
as an ornamental plant especially in The Netherlands. It is also a familiar species in North
America. Hyacinths are grown for
perfume in southern France. The odor
is heavy, sweet and quite overpowering.
Solvents are used to obtain the oil, which is generally greatly diluted. Oak Moss,
also called Mousse de Chene,
is a valuable addition to the raw materials of the perfume industry. It comprises various lichens that grow on
the bark of trees. The main sources
are European species of Ramelina
and Evernia,
particularly R. calicaris, E.
furfuracea and
E. prunastri. These lichens contain oleoresins that are
extracted by means of solvents. After
they have been collected, the lichens are dried. Then the perfume develops in storage. Oak moss not only has a heavy, penetrating odor and blends
well, but also has a high fixative value.
It is an essential element in lavender perfumes and soap and in the
better grades of cosmetics. Linaloe or Bois de Rose Several sources of this very
aromatic substance occur. Mexican
linloe is distilled from wood
chips of two species, Bursera penicillata
and B. glabrifolia. Cayenne linaloe
or Bois de Rose is derived from Aniba panurensis of the Guianas,
while Brazilian Bois de Rose
is from A. rosacodora var.
amazonia, a tree in the lower
Amazon basin. The product is widely
used in perfumes, soaps, and cosmetics and for flavoring of foods and
beverages. The oil is obtained by
distillation from the wood of Santalum album and related
species. The tree grows wild in India
and other parts of Southeastern Asia and is cultivated in many other
areas. The oil is used throughout the
Orient as a perfume and also in medicine.
It is an excellent fixative and is used in blends. The sweet-scented wood is made into chests
and boxes. Demand for sandalwood has
been very great, resulting in the eradication of the species in many
areas. Several substitutes have been
used. This oil is obtained from the
flesh leaves and young buds of Pogostemon cablin. The plant is a small shrub that grows wild
in Southeastern Asia and is cultivated in China. The leaves are fermented in piles and are then distilled. The dark-brown oil has a powerful odor,
resembling that of sandalwood. It is
one of the best fixatives for heavy perfumes. It is also used in soaps, tobacco and hair tonics. It imparts the characteristic odor to
cashmere shawls, which are shipped in patchouli-scented containers. This oil constitutes one of the
most famous perfumes of India and other oriental countries. It is obtained from Michelia champaca, a large tree
of the eastern tropics. The
conspicuous yellow flowers are very fragrant and are frequently worn by the
natives. The oil is removed from the
flowers by maceration or extraction and rivals ylang-ylang in its delicious
fragrance. Misc
Perfume Sources Some of the gum resins, mainly
frankincense and myrrh, have been used in perfumery for thousands of years. Other garden flowers that are
cultivated for their perfume include Heliotrope
(Heliotropium arborescensj), Lily
of the Valley (Convallaria majalis), Jonquil
(Narcissus jonquilla),
Mignonette (Reseda odorata), Narcissus
(Narcissus tazetta),
Clary Sage (Salvia sclarea)
and Tuberrose (Polianthes tuberosa). Oils from caraway, anise, cassia,
cinnamon, clove, peppermint, lemon, thyme wintergreen and zedoary have also
been used in the perfume industry, but these are discussed under other categories. <bot787> Red Coondoo (Mimusops
elengi L.) (fruit; dysentery
treatment; perfumes; paint oil) [India] Makrut Lime <bot745> Makrut Lime (Kaffir Lime) (Citrus
hystrix DC) (fruit; perfumes) [Sunda Islands] Essential Oils Used in Other Industries Camphor is an important essential
that is used in industry. Commercial camphor,
called camphor gum, consists of tough, white translucent masses or granules
with a penetrating odor and pungent aromatic taste. It is solid at room temperature, thus bearing the same relation
to the other essential oils that vegetable fats do to the fatty oils. It volatilizes very slowly. The oil is obtained by
distillation of the wood of the camphor tree, Cinnamomum camphora, and
native to China, Taiwan and Japan.
This is a very tall and striking tree with shiny, dark evergreen leaves. The tree has been widely introduced into
tropical and subtropical regions, mainly as an ornamental plant. The camphor industry is centered in
Taiwan. Earlier crude methods of
obtaining camphor were very destructive and the existence of the tree was threatened. Finally only trees 50 years of age or
older were used and every stages in the process was carefully regulated. The wood is reduced to chips or ground to
a fine powder and the leaves are also ground up. This is then distilled with steam for several hours and the
crude camphor crystallizes on the walls of the still. This is removed and must be purified
before it is ready for market.
Synthetic camphor from pinene, a turpentine derivative, gradually
dominated the market. The principal use of camphor has
been in the manufacture of celluloid and various nitrocellulose
compounds. It also has a wide range
of medicinal uses, both internally and externally. It is also used in perfumery. Borneo camphor,
obtained from Dryobalanops aromatica
of the east Indies, has been used as a
substitute. Cedarwood oil, along with clove
and bergamot oils, is one of several of the essential oils have a high refractive
index and are valuable as clearing agents in the preparation of permanent
microscopic mounts and for use with oill-immersion lenses. This inexpensive oil is obtained by steam
distillation from the heartwood of the Eastern red
cedar, Juniperus virginiana,
and related species. Wood chips,
sawdust, waste from the lead pencil and other industries, old stumps, roots
and even fence rails have been utilized.
Cedarwood oil is also used in perfumery, soaps, deodorants, liniments,
cleaning and polishing preparations and as an adulterant of expensive
sandalwood and geranium oils. It has
insecticidal properties and is used as a moth repellent and in fly
sprays. Essential oils are also useful as
solvents for paints and varnishes.
The most important of these is oil of turpentine. Various other oils, mainly eucalyptus oil
from Eucalyptus dives,
are employed in the flotation process for the separation of minerals from
their ores. Still other volatile oils
have been used in the preparation of cleaning materials and other industrial
purposes. |