Azulene and Chamomile
Éva Marie Lind,
One of the finest examples of
the transformation of how an essence changes its color through the
processes of distillation, as well as extraction, would be a short
introduction and a brief discussion to the Chamomiles and the
primary component, azulene.
“The term “azulene” was introduced by Piesse, who suggested
the name for the blue-colored constituent of Chamomile Oil” and related
plants, in the 1800’s. * It is interesting that the name was chosen for
color, rather than aroma. [Also Piesse is credited with classifying
fragrance to musical notes. Piesse discovered that perfumes were altered
and transformed from their initial aroma profiles when they were applied
to the skin.] In similar manner, through distillation, molecules can also
be combined, or even, in the case of azulene, created, to also alter an
essential oil’s fragrance.
are the compound group of which the constituent chamazulene, from
chamomile (cham for the plant, azulene
the compound group) resides. It is most frequently found within the
essential oil bearing plants of the Asteraceae family and is directly
responsible for the beautiful variables of blue we see within these oils
and extracts. These include Artemisia
arborescens (dihydrochamazulene) and A.
douglasiana, Tanacetum annuum, Achillea
nobile and Matricaria,
as well as the Elecampane (Inula
also reside in an assembly of oils beyond this grouping of oils
distinguished by the name "blue oils". These include many other
plants as well, Elemi (elemazulene), Eucalyptus (eucazulene) and
even Vetivert (vetivazulene). The quantity of azulene in the essential oil
will determine the percentage of color intensity within the oil; some
plants produce a plentiful composition of azulene, such as chamomile, that
has brilliant color, while others do not.
although linked to the color hues of blue, can also be green, violet,
blue/violet and red/violet. The brilliancy of this rainbow is
thought to be a result of the parent skeleton’s, a 5-member ring with 2
double bonds and a 7-member ring with 3 double bonds and a superb ability
to absorb light. As a whole, azulenes reside in the chemical
classification group of bicyclic unsaturated hydrocarbons, sesquiterpene
derivatives, with C15H18 as their empirical formula.
addition, some essential oils will have more than one azulene within its
chemistry profile, in which case the first will be labeled after it's
botanical and the second after it's color. I.e.: Vetivert contains both
vetivazulene (veti for genus)
and verdazulene (verd for
green). In addition, some oils may share the same azulene, such as with
yarrow, which is comprised of chamazulene, again, named such because it
was first discovered in chamomile.
are generally considered latent components, "present but not evident
or active" (Webster’s definition), within a number of aromatic and
herbal plants. Some azulenes occur naturally, within the plant, or the
oil, while others, such as chamazulene classically a component of German
chamomile, are created from a precursor within the steam distillation
process. The synergy of heat and pressure required for the distillation of
this plant, (constituents are what would be termed "high boiling,
requiring extreme and lengthy charge) and the inherent precursor within
Matricaria of matricin, combine to produce the azulene based constituent
of chamazulene. Once distilled over, it will both alter the color and odor
profile of the resultant oil and the longer the oil is distilled, the
brighter the blue the hue and the more diffusive the aroma.
amount of azulene within an essential oil, the percentile, will oftentimes
determine color composition. Some oils have quite a bit of azulene, such
as Chamomile and this profoundly alters its color.
In other essential oils, the azulene content is fractional and does
not affect the oil’s color scheme. It is interesting to note, that with
Roman chamomile, Chamaemelum nobile, the color profile preferred in the aromatic
industry, is that of pale golden amber. However, it has been shown,
that if distillation time is extended on this plant, its color hue will
also begin to change, as residues of azulene blend to the mix. In
addition, the time of day when your azulene rich plants are distilled will
affect the resultant azulene proportions. In general these plants are
distilled in the morning or evening, and with the plants needing an
extended charge, a long distillation, of between 7-13 hours is needed.
Distillation generally begins in the morning or evening, due to
preferred climatic harvest and "cooking" temperature hours and
oftentimes, as in the case of Blue Chamomile (Matricaria recutita), will require additional cohobation, (the
re-distillation of the waters). Maintaining these guidelines, not only
ensures a nice proportion of chamazulene, but as well, the azulene
derivative of bisabolol, which in combination, affords chamomile its
wonderful reputation as an anti-inflammatory. Also it is important
to note that the age, the plant’s origin and the storage conditions,
will often affect the percentage range of azulene a distiller can expect
to recover, or "pull over" in their oil.
an interesting perfumery note, Arctander relays an experience where the
method of extraction, not distillation, used to acquire the absolute of
chamomile, could actually capture an "extraordinarily high"
level of azulene. Not much relationship to the uses for clinical
therapy, as extracted oils are generally not applicable, however, for
fragrance and natural perfumery, which chamomile absolute is sought after
for, it is indeed a viable factor. He continues with the notary
remark that it is the content of azulene in combination with other
hydrocarbons contained in chamomile that can influence a
"rubber-like" note, the fragrance influencing associated to this
compound group. It is also interesting to note, as we move to the
time when we are desiring less man-made tampering of natural perfumery
elements, that the absolute of chamomile is being met with more
adulteration, with the entry of the modern synthesized version of
The beauty of oils rich
in azulene components at large enough percentages to influence their color
profile, as the blue oils, is that you can easily determine when an oil
has reached it's prime, has oxidized (subjected to air and light), through
it's color changes. Your more yellow oils will turn muddy with tinged with
brown and your blue oils will meld into a black green - like dirty moss.
For this reason, when you receive your essences rich in azulene, it is
terribly important to use a professional/perfume blotting stick (pbs) to
test the oils as soon as they arrive - and return if it is not fresh. Dark
bottles are going to obscure this until you do. You must also keep your
bottles tightly capped, cool and stored in an area with reduced light.
This is essential to keep your oils fresh. One of the prime challenges
with oils rich in azulene, is keeping it "fresh", but the
beauty, is that in its "look and "temperament" it lets you
know not only aromatically, but visibly, when it has gone off.
SOURCES OF REFERENCE:
Arctander, Steffen, PERFUME &
FLAVOR MATERIALS OF NATURAL ORIGIN, ©1961
the introduction of the term azulene in Volume II, Page127, referring to Compt.rend.
57 (1863). Chem News 8
(1863), 245, 273.
College for Aromatherapy Medical Professionals, C.A.P.M
Guenther, Ernest , THE ESSENTIAL
OILS, VOL 2. Krieger Publishing, ©1952
Kerr, John. Editor,
ON AZULENES, Aromatherapy Today, ©?
Price, Shirley, AROMATHERAPY FOR
HEALTH PROFESSIONALS, CH 1-2, Essential Oil Science, Churchill
Rose, Jeanne. THE BLUE OILS, AROMATHERAPY QUARTERLY, ISSUE 46, ©1995
9. PERSONAL RESEARCH - PAPERS ASSEMBLED FOR ADVANCED AROMACHEMISTRY CURRICULUM MODEL ©2002, BY EM LIND, BASED ON THE ABOVE RESOURCES - NAMES REQ. TO BE ANONYMOUS.
Bio: Éva-Marie Lind-Shiveley has specialized in holistic aromatherapy for
15 years. She has practiced as a clinical aromatologist and held the
position of program lead and department dean at private career colleges in
natural health. She has also worked in research, marketing and
design for aromatherapy product-based companies. A resident of
rights reserved 2004 for The Aromatic Plant Project.
No part of this article may
be used without the prior permission of Eva-Marie Lind.
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