HOW THE ESSENTIAL OILS ARE PRODUCED
Essential oils can be extracted in a variety of ways. To obtain any of these essential oils in their purest form would require the proper equipment, and a sophisticated laboratory where the oil then, could be separated from a fresh plant.
To determine which method should be employed to separate the oil varies on the type of plant. However, the most common separation process used to extract the essential oils is called Steam Distillation. The process begins by suspending the plant over boiling water, in a closed container, until the steam is raised to reach the plant. Subsequently, the essential oils are quickly taken by steam through a long tube that is surrounded with cold water. The cold water allows the vapor to rapidly cool off and condensate. A majority of essential oils cannot be blended with water. Therefore, both follow different paths; the essential oils through a small vial collector and water into a large bucket.
Various processing techniques can produce different versions of the same essential oil. For example, Peppermint oil is constantly redistilled, and passes through the steam distillation twice to extract the oil. When peppermint oil is distilled for the first time, it smells is similar to mint, but the smell is hard as well as its taste. When distilling peppermint oil for a second time, the hardness disappears in favor of light, freshness, and flavor. As a result, this causes many people to associate types of mint with chewing gum and candy. The lighter version is considered superior and worth the extra work to distill the oil twice. Most mint oils offered today are re-distilled.
The process of expression press essentials oils from citrus peels and seeds such as orange, lemon, lime, and grapefruit. These are usually left out by manufactures of citrus juices. This technique is similar to the technique of pressured olive oil.
The “Effleurage” is an ancient oil extraction method, rarely used today, except in parts of France. It is not so popular because it is a long, delicate, and expensive process. Fragrant flowers are placed in hot solid sheets made of fat, which absorbs essential oils (originally sheets were made from animal fat or butter, but now are from solid vegetable fat).
The technique of carbon dioxide is a fairly new technique for the extraction of essential oil. Gas under high pressure must be maintained at a constant temperature. The equipment for this process is quite expensive. Therefore, only the most expensive essential oils are extracted with carbon dioxide. The oils used in this process consistently produce a smell that is similar to the plant because the extreme heat is not used during the process.
Another technique to extract essential oils is through the extraction of solvents. This process requires little heat, therefore, it is possible obtain essential oils which fragrance will not be destroyed or altered during the steam distillation process. The plant is dissolved in a liquid solvent solution such as Hexane, Heptane, or Methylene Chloride.
These chemicals then extract the essential oils from the plant. The plant must be removed and the solvent turned-off under a vacuum machine or a centrifugal force as it will help separate the essential oil. Since the solvent has a lower boiling point than the essential oils do, the solvents will evaporate before the oils do. Finally, the solvent can be cooled back into a liquid, to be reused. Together with the essential oil, the fat, wax and heavy oils can be extracted.
The field of psycho-aromatherapy focuses on the psychological potential of essentials oils as well as the primary effects of fragrances. Psychotherapeutic uses have been found to produce positive results in which the oils can be obtained more rapidly through the odor than any another method. Massages can be very beneficial especially for emotional and stress-related conditions. When it comes to this subject, our olfactory system plays a role that is worth mentioning.
Olfactory System: When we smell a rose, its sweet fragrance enters through our nose. Its scent is made up of tiny aromatic molecules or “particles of energy”, and each has a specific shape. Located at the top of both sides of the nasal cavity is the olfactory epithelium, which is covered by a thin mucus layer. Once it is in the nose, the aromatic molecules migrate through the mucus into the tissue surface, and cause about 10 million of our olfactory nerve cells to respond. Each nerve cell carries a bundle of tiny hairs or cilia, and is equipped with different receptor cells to closely match the shape of each aromatic molecule; similar to using a key for the lock. These receptors are extremely sensitive and capable of carrying vast amounts of information.
The receptors then transmit the smell through nerve fibers in the form of electrical impulses, to the olfactory bulb, which passes the stimulus to other relevant parts of the brain. This chemosensory information is then translated into physiological and behavioral effects, and finally, by comparison with the memory contents, in a conscious olfactory experience.
For example, the smell of the rose goes directly to the limbic system and the prefrontal part of the brain, where memories associated with past fragrance are evoked immediately. The limbic system is the area where feelings and instincts are recorded. This system was previously developed in our ancestors because in ancient times, humans depended on their olfactory sense for survival. It was then when the “civilized” man became dependable on the latest developments of the cerebral cortex, which filters incoming man information, as well as control of the speech and intellectual knowledge.
Depression and anxiety: The potential therapeutic of odor has been recognized for thousands of years, in the West, without being used completely. Recently in this century a systematic research has been conducted into this area, with promising results.
In the beginning of 1920, two doctors, Giovanni Gatti and Renato Cayola, published a report called, “Action of the odors in our nervous system”, in which they explored the effects of essential oils in two opposing states of anxiety and depression. The experiment was conducted using a piece of cotton infused with essential oil. The cotton was then lightly pressed on the face, and the aromatic solution was then sprayed in the environment to be inhaled. The doctors measured changes in pulse rate, blood-circulation, and deep breathing apparatus.
The results showed that odors can quickly influence the brain because the inhalation method produced almost an immediate effect. This is in contrast to oral administration in which essential oils would be slowly absorbed via the digestive tract. Essential oils used to treat individuals in anxiety states are called sedatives and included the following: Chamomile, Melissa, Neroli, Petit Grain, Opoponax, Asafoetida, and Valerian. On the other hand, stimulating oils were efficient in the treatment of depression. These oils include: Angelica, Cardamom, Lemon, Fennel, Cinnamon, Clove, and Ylang Ylang (an aphrodisiac). The researchers also noticed that some odors were stimulating in small doses, but sedatives when were used in large doses. They concluded that “The olfactory sense has, by reflex action, a huge influence on the functioning of the central nervous system.”
Of course other books have been published, such as “Aromathérapie” by Gattefosse, explaining the action of essential oils on the nervous system. Some of the oils mentioned were Hawthorn, Heliotropine, Vanilla, Cajeput, Bay Laurel, Neroli, Melissa, and Valerian as incidents tranquilizing effects. Dr. Jean Valnet published his excellent book “The practice of Aromatherapy” suggesting that many essences are stimulants such as Pine, Borneo, Geranium, Basil, Sage, Savory, Rosemary, and Lemon. Other leading researchers are doing studies in this area, such as Paolo Rovesti, professor at the University of Milan. Rovesti measured the restorative effects of pure essential oils in patients suffering from hysteria or nervous depression. Also, the University of Cambridge along with the University of Wales made recent studies showing the effects of Chamomile Oil to the psychological system.
The Response to the Brain
The first study of the effects of fragrances on the brain was made by Moncrieff using an electroencephalogram (EEG) machine. This machine measures alpha brain waves, when the alpha waves incremented indicate relaxation, while the increase of beta waves showed stimulation. John Steele conducted experiments using the method “mind-mirror” a portable EEG machine with multiple channels to evaluate effects of various essential oils on patterns of rhythms in the brain. The method “mind-mirror” is beneficial to the study of altered states of consciousness. Torii professor of Toho University of Japan, initialized a program to distinguish those essential oils having sedative effects on the nervous system and those who have simulative effects. Recently Dr. Knasko showed that in environments mock odors can affect the mood and levels of stimulation, in other words, a mental idea can override a physical phenomenon. Researchers Van Toller and Kobal, studied brain function during the stimulation olfactory of effects of fragrances on both sides of the brain, the results were more than amazing. It is, therefore, true to say that certain smells tend to produce specific physical effects which are common to everyone – stimulating or relaxing, pleasant or unpleasant – subjective psychological factors can override the most objective physiological response or at least emphasize the individual reaction. Physiological and psycho-chemical responses may be predicted, while the emotional or physio-chemical reaction cannot.
Emotions and the olfactory sense
It is said to be that many diseases have their roots in the mind, due to a negative picture of the person or underlying fears. The mental states like anxiety, irritation, or anger cause physical changes in the body such as the increment of the heartbeat, breathing, and muscle volume. The influence of one’s emotions and mood is significant because “the way you feel can determine what you think, perceive, remember, and ultimately how to behave.” Since the body and mind are inextricably linked, a change in the psychological or emotional disposition of a person can have dramatic health outcomes, as a whole. Professor Howard Ehrlichmam at the University of the City of New York found that smells of almonds stimulated pleasant memories on the individual, while pyridine smells (like urine) creates unhappy memories. The psycho-biologist of Yale University, Gary Schwartz, found how the effects of the fragrances work on stress, using a variety of methods, including biofeedback, he concluded “The smells that enter through our nose can be absorbed by our blood stream, causing a chemical effect. At psycho- biological level, when we smell a pleasant fragrance, taking slow and deep breaths, the effect creates relaxing and breathing patterns, as much as we do it while meditating. The olfactory input can also be used as a distraction, focusing our attention on odors or inducing positive memories and emotions.
Our memory and mood
We know that certain smells can evoke powerful emotional memories and often tend to lead to personal meanings connected with individual experiences of our childhood. The French psychoanalyst André Virel uses scents to help bring memories neglected by their patients. The odors can also be associated with specific feelings of people and places. The word ‘atmosphere’ is derived from the Greek word ‘atmos’, meaning ‘steam’, showing the connection between smell and mood. The phenomenon ‘evoked olfactory memory’ of a particular odor brings memories of the past, often with a vivid visual image and a positive mood. The “International Flavors & Fragrances Inc.” instituted a program aimed to evaluate the aromatic effects on subjective states of mind, using both psychologic and physiological stimuli. The physiological reactions were measured using a galvanic skin response, skin temperature, muscle tension, heart palpitations, breathing, and especially blood pressure. The psychological response, to specific odors, was recorded by self-reported subjective. In a series of experiments that were made, where several ‘living flowers’ (thrush, Osman thus, Douglas fir, hyacinth) were given to 40 women to measure the ‘mood profile’ and the following was found: the mood varied according to the flowers, creating happiness, relaxation, irritation, depression. Through this experiment was proven the effects of how odors can influence moods, as stimulating or relaxation.
The future of Aromatherapy
The science of Aromatherapy promises to revolutionize our workplace and households. In the short future, ventilation systems of offices will release scents to positively shape the moods of its employees, and also improve the interaction of human relationships. The Aromatherapy revolution is already underway, as shown in hotels, airplanes, and hospitals. Specific mixes of essential oils are being used in gyms (sauna) to improve the atmosphere and encourage clients. Also in the cinemas and theaters, its use will be meaningful.
Psychologist Susan Schiffman of Duke University has developed ideas on the utility of essential oils. For example, the essence of chocolate spray when applied, on the back of the tongue, can help curb a craving. Also, Schiffman found that the smell of pears helps relieve pain. Schiffman’s research found that the wiring of the nose receptors travels to specific sites in the brain, and portends tremendous advances in the therapeutic use of scents.
These possibilities are of tremendous value because of the limitations imposed by the blood-brain barrier. This is the lipid membrane covering the capillaries carrying blood to the brain. So far it has been impossible to point that the mental illness known as Alzheimer can be eradicated using conventional drugs simply because the molecules are large enough to penetrate the blood barrier-brain. On the other hand, our olfactory nerves have evolved after the brain neurons, and they are the only ones not protected by the sheath. As a result, they offer unique and natural means of direct treatment to the brain.
Soon the fragrance will be able to directly influence the mind and treat areas of the brain involved with diseases, emotions, and even our though process. The more we moderate investigations using the proper ‘dynamic suggestion’, the more we can evoke subconscious strata with the intention to work on behavior modification, cognitive enhancement, and even research in controlling criminal behaviors.
We hope that this short article may have helped you gain an insight into the vast field of Aromatherapy. For those interested to know more about this science, we have included some useful sources to allow you to explore the enormous potential of the Aromatherapy that frankly Ladies and Gentlemen, is already here.
PLEASE, YOUR COMMENTS ARE VERY WELCOME.
Part 2 of 2
The Aromatherapy companion, Victoria H. Edwards
The Encyclopedia of Essential Oils, Julia Lawless
Aromatherapy for Dummies, Kathi Keville
Aromatherapy and the Mind, Julia Lawless
The Essential Oils, Guenther E
Herbs and Aromatherapy, Metcalfe, J
Purdue University, www.newcrop.hort.edu/newcrop/default.html
Information about Aromatherapy, www.geocities.com/~aromaWeb
Database about aromatic and medicinal plants, www.scs.leeds.ac.uk/pfaf/D_intro.html
Frontier Herb Company, www.fragant.demon.co.uk