Distillation
A master distiller must oversee the entire process by harvesting at just the right time for the plant maturity and distilling with the proper temperature, pressure, and time, which varies with different plant material.
Distillation converts the volatile liquid (the essential oils) into a vapor and then condenses the vapor back into a liquid. This method is more commonly used in essential oil extraction than any other extraction method. In addition to its popularity it is also the most cost effective.
Traditional Steam Distillation
Steam distillation is a separation process for materials that are temperature sensitive like essential oils. Today, the traditional method of steam distillation is still used around the world. Plant material is loaded into the extraction chamber and tightly compacted. As the boiler heats the water, steam is released into the bottom of the chamber and starts to travel upward, saturating the material.
The steam impregnates the plant fiber, causing it to release the oil molecule as a gas from the molecule pocked or channel. Then the steam carries the gas to the condenser where it goes through a phase-change condensation as it passes through the cooling process in the swan neck and liquefies into water and oil.
The water and oil mixture then flows into the separator where the oil can rise to the top of the water to be poured off into containers.
In each of these processes as the steam rises, it carries the released oil vapor into the condenser where the water and oil vapor convert to a liquid and flow into the separator so that the oil can rise to the top of the water and be drained off. There are many variables in steam distillation. Subtle differences in equipment design and processing conditions can translate into huge differences in essential oil quality. The size and material of the extraction chamber, the type of condenser and separator, and the temperature and pressure can all have a huge impact on the oil quality.
Distillation is as much a science as it is an art. If the pressure or temperatures is too high, or if the cooking chambers are constructed from reactive materials, all may not be therapeutic or genuine essential oils Water Distillation/Simple Distillation The plant material is loaded into the extraction chamber filed with water, which is heated to soften the plant fiber so that the oil molecules can be released. As steam begins to rise, the oil molecules are released as vapors, which are carried with the steam into the condenser. The cooling water in the condenser converts the steam to water and the vapors to oil.
The oil and water mixture continues to flow into the separator where the oil rises to the top of the water so that it can be drained off into containers. Clove and nutmeg are distilled this way.
Hydro Diffusion
When essential oils are extracted using hydro diffusion it is a type of steam distillation, and only varies in the actual way in which the steam is introduced into the still. The steam is fed in from the top onto the botanical material instead of from the bottom as in normal steam distillation.
At the bottom of the still is a grill that holds the botanical material in place. The condensation of the oil containing steam mixture occurs below the grill. The main advantage of this method is that less steam is used, shorter processing time and a higher oil yield.
Hydro Distillation
Resinous material like frankincense and myrrh are extracted through this method of hydrodistillation. The resin is immersed in boiling water that is in constant motion while steam is injected into the chamber. The resinous gas is then released into the steam, which carries it to the condenser where the steam and vapor are gradually cooled to a liquefied form.
The water and oil mixture travel into the separator so the oil can flow to the top of the water and be poured off into containers. Resinous materials such as frankincense and myrrh are distilled in this manner.
First things first. Essential oils should be packaged in dark coloured glass, since this filters out the suns ultra-violet light. Until quite recently, dark amber was always the colour of choice in glass bottles as can be seen from old-style medicine bottles. Today, dark shades of blue, green and violet have become more popular and they all offer some protection to your oils.
However, no matter what the colour of bottle is, you should never leave oils in a place where the sun will shine directly on them – like on a window shelf in the bathroom, for example. Over a period of months this will dramatically speed up the process of oxidation (deterioration) due to them continually heating up and cooling down. Choose a cool, dark place to keep them safely away from heat and also inquisitive children.
When using a new essential oil on the skin, it is recommended that you first do a sampling test to see if you have allergies or sensitivities to it. Before you begin, check to be sure the label of the essential oil you’re using says that it’s 100% pure essential oil. If it doesn’t say it, chances are it is not and it should not be used on the skin or in aromatherapy applications.
To do a skin test:
Dampen a cotton ball slightly with a carrier oil such as sweet almond oil or olive oil.
Add a drop of the essential oil you’re wishing to test onto the cotton ball. Touch the moistened cotton bud to a small patch of skin on the inside of the elbow, back of the wrist, or under the arm Cover the spot with a bandaid and protect the area from water for 24 hours. If irritation occurs, generously apply olive oil or aloe vera gel to the area then wash it thoroughly with soap and water. If there is itching, redness, or other signs of an allergy or sensitivity to the sample testing, these are indications that you shouldn’t use that oil.
You may wish to test the carrier oil separately first if you have not used it topically before. Many references will suggest just applying a drop of the essential oil directly to the skin. Most essential oils should not be used undiluted -aka “neat”- on the skin and testing them in that manner shouldn’t be required to see if you have a reaction.
The use of essential oils is not recommended for the very young or aged, or pregnant/nursing women. It is the belief of this site that essential oils should not be used internally. A qualified aromatherapist will be able to guide you in the proper use of oils including how to dilute them properly before use. Consult a reputable and experienced aromatherapist for guidance. It is also recommended that you seek professional medical advice before using essential oils. The information provided on this site is for documentation purposes only and is not guaranteed to be accurate or complete.