HISTORY OF ESSENTIAL OILS
Due to the worldwide usage of essential oils for centuries, it is difficult to pinpoint exactly which culture began using them first, but the first records of essential oils allegedly come from ancient India, Persia, and Egypt. Greece and Rome also engaged in the widespread trade of aromatic oils and ointments with Eastern countries. Each culture had various uses for them ranging from health treatments to spiritual practices. Their herbal preparations included incense, perfume, clothing and fabric fresheners, medicine such as pills, powders, and suppositories, ointments, scented baths, and aromatherapy massages. In many cultures, aromatic oils were believed to create a union with the gods and were held in such high regard that they were used only by a select group of privileged people, such as priests.
Arabs were the first to develop the technique of plant distillation to extract essential oils. They were able to replace the fatty oils that were used as solvents for extraction with a new solvent that they created by distilling ethyl alcohol from fermented sugar. During the Middle Ages, this knowledge of the distillation technique spread to Europe and its pharmacies specialized in distilled products.
WHAT ARE ESSENTIAL OILS?
Essential oils are organic, concentrated, highly volatile, hydrophobic liquids that naturally occur within and are secreted by tiny structures located in a plant’s various parts – the seeds, grasses, roots, barks, stems, leaves, fruits, flowers, resins, zest and wood of plants. They are also referred to as volatile oils, ethereal oils, or aetherolea. Despite the word “oil,” they feel less viscous than oil, having more of a watery texture.
Inhaling the scent of a flower equates to experiencing its essential oil’s aroma. These oils were given the name “essential,” because they were believed to capture a plant’s essence, that is its odor and flavor. The nature of an oil depends on the plant itself and on the botanical family and species to which it belongs. An essential oil gets its name from the plant from which it is derived. For example, the essential oil from the Lavender flower would be called Lavender Oil.
The oils contained within the plants are aromatic, lending plants their distinctive fragrance while also promoting their self-protection and pollination; it is likely that oils from a plant’s wood, leaves, and roots help the plant guard itself against attacks from parasites and animals and allow them to adapt to their environments, which are sometimes harsh. A pure essential oil then is the plant’s defense mechanism and is more powerful than the botanical itself due to the concentration of healing compounds collected in the oil.
As already mentioned, an essential oil is an aromatic compound that is volatile in nature, which is to say it is a molecule that rapidly changes states from solid or liquid to a gas at room temperature. The speed with which it changes states is the reason for the name “volatile.” In chemistry, this refers to a substance’s tendency to vaporize readily. This is what quickly transports the aroma of an essential oil through the air, causing it to activate olfactory sensors in the nose. The volatile aromatic compounds also govern the physiological benefits offered by an oil – this is precisely what makes essential oils ideal for use in aromatherapy, a holistic practice that promotes a sense of well-being and harmony of body and mind through the power of scent.
COMPOSITION OF ESSENTIAL OILS
Essential oils are comprised of a complex mixture of constituents, a single essential oil sometimes containing hundreds of them. The specific ratio of the constituents gives the oil its specific wellness-enhancing and therapeutic qualities. The most commonly found classes of essential oil constituents include: Monoterpenes, Sesquiterpenes, Diterpenes, Alcohols, Phenols, Aldehydes, Ketones, Esters, and Oxides. Due to the health-supporting and cleansing properties that many of the constituents share, almost all essential oils are anti-septic and many also have anti-fungal, anti-viral and anti-bacterial activities.
The appearance of essential oils ranges from being colorless to being any color of the rainbow, and sometimes the color of the oil points to its therapeutic qualities. For example, being blue in color, Chamomile Oil is useful for aromatherapy massage on a person experiencing “red hot” emotions, as the blue represents its classic “cooling and soothing” effect and counteracts any negative physical and psychological feelings. Oils such as Patchouli, Orange, and Lemongrass are amber or yellow in color and their bright happy colors can easily help a person determine what they are best used for – as mood boosters! Younger plants yield more essential oils than older plants, but the latter produce oils that are more resinous and darker in color due to the continuous evaporation of the oil’s lighter fractions. Sometimes their colors are a result of the extraction method while at other times the color of the plant material affects the color of the final product. While Chamomile is not blue, it contains a component called Chamazulene, which turns the oil an inky blue color during the distillation process.
EXTRACTING ESSENTIAL OILS
A single drop of an essential oil can be potent enough to have powerful health benefits. Microdroplets of oils are stored within a plant’s glands. After these droplets are diffused through the gland walls, they spread out over the plant’s surface and then evaporate, filling the air with a pleasant aroma.
Plants with the strongest scents are usually found in tropical regions where there are higher temperatures, which causes plants to produce more biogenic volatile organic compounds while also extending the growing period throughout which their fragrant compounds are generated. Typically, it takes many pounds of plant material to produce a small amount of essential oil. In the case of Rose Oil, 65 pounds of rose petals are required to make only 15 mL of oil.
The following methods are the ways to extract essential oils: Enfleurage, Expression, Steam Distillation, Solvent Extraction, Carbon Dioxide Extraction, Fractional Distillation and Percolation, Phytonic Process, Maceration, Mechanical Pressing, and Distillation.
|Enfleurage||Delicate plant parts like flowers, roots, and leaves are soaked in fatty oils to extract their essential oils|
|Expression||A rotating mechanical device with spikes punctures the fruit rind to release its essential oils. This method is also called “Cold Pressing.” It is specifically meant for citrus essential oils (Lemon, Bergamot, Orange, etc).|
|Steam Distillation||A current of steam is injected into the still containing botanical material, usually at high pressures and temperatures.|
|Solvent Extraction||One of the components of botanical material dissolves in a particular liquid (solvent) and the non-volatile components, such as waxes and pigments, are separated/removed by filtration. This method is also called “Liquid-liquid Extraction.” It emcompasses Enfleurage, Maceration, and Carbon Dioxide Extraction.|
|Carbon Dioxide (CO2) Extraction||Pressurized CO2 turns into a “supercritical” liquid that is pumped into a chamber containing plant material. Despite being a gas it has liquid properties, which allows it to act as a solvent that pulls out the plant matter’s essential oils.|
|Hydro-Diffusion (Hydrofusion) Extraction||This method is similar to steam distillation except that the steam enters through the top of the chamber rather than the bottom. The plant material lies on top of a grill, so the steam “percolates” down through the plant material, much like coffee passes through a filter. This method is also called “Percolation.”|
|Phytonic Process||This method uses non-chlorofluorocarbons (non-CFCs) as a solvent. The oils produced are called Phytols. The extraction occurs at or below room temperature, which means the oil is not degraded by high temperatures. These oils are pure and as close to the natural plant properties as possible. This method is also called “Florasol Extraction.”|
|Maceration||A solvent (Menstruum) is added to cut/ground/crushed plant material and the mixture is allowed to stand for a certain period of time. The liquid is strained and the solid residue is pressed for any remaining liquid. Both strained and expressed liquids are mixed then filtered.|
|Oil Soak||Plant material is soaked in a carrier oil. After 2 weeks, the solids are strained the remaining infused oil is the final product.|
|Water Distillation||Plant material is submerged in water that is heated until the plant material becomes soft. The oil vapors rise, enter a condensation chamber, and cool off. Here, the steam becomes water again, but the vapors become the oil. The oil is then separated from the water component, which becomes the “floral water” (hydrosol).|
The most popular extraction method for essential oils is steam or water distillation of the roots, bark, stems, leaves, flowers or other parts of a plant. With the aid of steam, this process separates the plant’s healing oil-based compounds from the water-based compounds to produce a single, concentrated aromatic oil.
ESSENTIAL OIL CONTRAINDICATIONS
Generally, when aromatherapy is approached with the proper cautions it does not lead to any adverse side effects and can promote well-being both physically and mentally. On the other hand, due to their powerful potency and their capacity to act as natural medicine, essential oils are best avoided under the following circumstances: when uninformed about essential oil properties, when undiluted, when pregnant or when pregnancy is suspected, while on medication, near open flames, near eyes, when exposed to sunlight or tanning booths, near children and pets, if prone to allergies or sensitivities, when room lacks proper ventilation.
ESSENTIAL OILS VS. FRAGRANCES
The terms “essential oil” and “perfume (oil)” are often used in place of each other due to their aromatic qualities, but there are significant differences between them. Essential oils are natural, volatile, aromatic compounds extracted from botanicals. Fragrance oils are artificial and synthetically created by chemists, who reproduce the chemical composition of a plant’s components; however, they do not contain the same therapeutic benefits as essential oils, and thus they are not used in aromatherapy, as the body does not absorb the structures of the synthetic molecules in the same way it absorbs natural molecules. The similarity between essential oils and fragrance oils is that both types of oils can be found in cosmetics such as moisturizers, soaps, and of course perfumes as well as odorant products used around the house, such as scented candles, diffusers, and sachets for laundry.
Sometimes the term “fragrance oil” or “perfume oil” is used to refer to essential oil blends, which are combinations of several essential oils even though essential oils are not artificially made. The advantage of using essential oil blends is that money will not be spent on purchasing individual oils, but the downside is that the oils contained in a blend will not be customized to the individual’s preference.
WHAT AFFECTS ESSENTIAL OIL QUALITY?
It is beneficial and advisable to purchase quality essential oils from a reputable source that specializes in supplying essential oils that are therapeutically active in order to receive their health benefits. Because the purpose of an essential oil is aromatherapy, it is best to avoid using commercial grade oils, which are usually better suited to the industries of perfumery or flavoring. For an essential oil that is 100% pure and natural, and ready to be used in aromatherapy, it should not have anything added to it, as this will compromise its therapeutic properties.
Regardless of how pure an oil claims to be, its composition can vary and is determined by the following factors, all of which impact the final quality of the oil: the scarcity of the botanical, the country of origin, the year the crop is grown, the season, the weather, the geography of the land, the method and duration of distillation, the distiller’s quality standards and how much oil the botanical yields.
The quality of an oil may be identifiable by its label, but it is important to keep in mind that Health Canada and the Food and Drug Administration do not regulate essential oils, thus there is no way to validate the truth of the claims on the bottle label. One hint that points toward an essential oil possessing a good quality is the printed Latin name of the botanical from which the oil was extracted. Also, despite the chance that a label could mislead with the claim of being a “pure” or “100%” essential oil if a label claims this there is a better chance that it is of high quality. Oils with the terms “fragrant oil” or “potpourri oil” on their labels are synthetic, so while they may smell like essential oils, their effects will not be therapeutic and may instead cause an allergic reaction.
To ensure that an essential oil can be used for therapeutic purposes, check for a “Canada Organic,” “United States Department of Agriculture (USDA) Certified,” or “Organic Certified” seal. For more information about the quality that these seals guarantee, have a look at our article titled “Safe Cosmetics.” All of the Organic Essential Oils at New Directions Aromatics are NOP/USDA certified. This means they are 100% pure, natural, and free of herbicidal residue, pesticides, and synthetic fertilizers.
STORING ESSENTIAL OILS
Essential oils are typically sold individually in small, dark individual glass bottles that prevent exposure to light, which would cause them to oxidize and diminish their fragrances as well as their therapeutic properties. The oils may even evaporate. The most common bottle colors are amber and cobalt blue. Oils will cause plastic bottles of any color to deteriorate if they are not PET AND HDPE plastics.
The bottles must be tightly sealed by their caps, as exposure to air will also lead to oil oxidization. The caps should only be taken off when the oil is in use and then it should be recapped immediately afterward. Screw-on bottle caps are recommended over lids with droppers and bulb because despite the rubber droppers making application easier, the rubber will eventually deteriorate and possibly leak into the oil. Oils should not be stored on surfaces that are easily damaged such as paper, plastic, or painted or polished surfaces, as oils can stain these materials.
The ideal spot for storing essential oils is in a cool, dry place with a stable temperature away from direct sunlight, as sunlight will cause oxidization. Oils may be stored inside a refrigerator to prevent exposure to air, direct sunlight, and fluctuating temperatures, and in this case, the optimal temperature is between 5 and 10 áµ’C (41 and 50 áµ’F). Although the oil might coagulate, this will not have an unfavorable effect on the quality of the oil, which should return to its liquid state after thawing outside the refrigerator and returning to room temperature. Oils should not be kept in the freezer, as freezing may damage the oil quality. Due to their flash points – temperatures at which a liquid’s flammable vapors mix with air and ignite when exposed to heat – essential oils should be kept away from heat sources such as stovetops and candles or they may catch fire.
To ensure safe usage of an essential oil so that it will not cause a reaction, it is important to check the “best before” date.
TYPES OF ESSENTIAL OILS & CONSTITUENT CONCENTRATIONS
The following chart highlights the various essential oil concentrations along with a few examples of the numerous oils that fall into the category of the specified oil type:
|OIL TYPE/MAIN CONSTITUENT||BENEFITS||ESSENTIAL OILS|
|Citrus Oils||These oils are believed to be uplifting and thus supportive of the immune system.||Lemon|
|Monoterpene-rich Oils||These oils are known to be airborne deodorizers.||Frankincense|
|Aldehyde-rich Oils||These oils are believed to combat fungus and to soothe and cool the skin.||Lemongrass|
|Ester-rich Oils||These oils are sedative, promoting a sense of relaxation and stress-relief.||Clary Sage|
|Oxide-rich Oils||These oils are reputed to be decongestive and mentally motivating.||Eucalyptus|
|Monoterpenol-rich Oils||These oils have traditionally been used to nourish the skin and to soothe inflamed skin.||Geranium|
|Ketone-rich Oils||These oils are believed to be mucolytic and, when applied topically, are known to be cooling.||Dill|
|Phenol-rich Oils||These oils are reputed to be anti-infectious.||Oregano|
|Sesquiterpene-rich Oils||These oils are ideal for inflammation and pain issues. They are believed to promote a sense of calm and focus.||Cedarwood,|
|Sesquiterpenol-rich Oils||These oils are believed to show sedative and anti-inflammatory activities.||Carrot Seed|
PRICING OF ESSENTIAL OILS
Essential oil prices depend on crop and growing conditions and both the suppliers’ and each company’s resources, and their process and production practices, which give insight into their quality and control standards. A buyer should be cautious about avoiding buying only the cheapest oils, as they may not necessarily have the same therapeutic properties as more expensive oils. One company’s high prices might be due to the care given to their distillation, shipment, and storage of their oils. Certified organic oils are also more expensive than non-organic or “conventional” oils. The prices for fragrance oils tend to remain steadily reasonable. Though there are some essential oils with lower prices than their synthetic versions, they are also more volatile. These oils include Lemon, Orange, Pine, and some varieties of Lavender.