By Bruce Carroll:
Essential oils are concentrated, natural aromatic plant essence. They’re usually distilled, extracted by solvents, or pressed. They’re also volatile oil. They differ from fragrance oils, like perfumes, which only mimic the scent of the plant without having the medicinal benefits. Essential oils are used in a wide variety of consumer goods, like soaps, cosmetics, perfumes, detergents, pharmaceuticals, soft drinks, distilled ethanol beverages and more. It can take more than 200 pounds of a flower to make a single pound of essential oil.
The official definition of aromatherapy defines it as “the therapeutic application or the medicinal use of aromatic substances (essential oils) for holistic healing.” In 1997, the International Standards Organization determined that essential oils are a “product obtained from vegetable raw material, either by distillation with water and steam or from the epicarp of citrus fruit of a mechanical process, or by dry distillation.” Essential oils have been found to have various degrees of antimicrobial activity and are believed to also have antiviral, nematocidal, antifungal, insecticidal and antioxidant properties.
NOTE: Ingesting or swallowing essential oils is NOT RECOMMENDED as this concentrated form can damage your liver and kidneys
Distillation
Distillation is the process in which a liquid is vaporized and turned into steam, then re-condensed and turned back into a liquid and collected in a container. It’s a separation technique that can be used to either increase the concentration of a particular compound in a mixture or to obtain almost pure concentrations from the mixture. The process of distillation exploits the differences in the boiling points of the components in the liquid mixture by forcing one (or more) of them into the gaseous state.
This is not a chemical reaction but a physical separation process. The industry is mostly focused on the three types of steam distillation which include water, water and steam and direct steam, which is the most efficient method.
Types of Stills
There are several effective still designs, with the most common being the pot still or short path stills.
- Pot Still
- Reflux Still
- Short Path Still
- Retort Still
These can be operated as open-loop or closed-loop systems. For the homesteader, an open loop pot still is typically what is used, both for the distillation of essential oils in addition to ethanol production. Some stills can serve multiple functions (i.e., pot still/reflux still).
Distillation methods are better for some types of fragrant flowers such as rose petals. Solvent methods are more suitable for expensive, delicate and thermally unstable plant matter like jasmine and hyacinth. Water distillation is the most common method for citronella oil extraction. Tinctures extend useful shelf life for up to 10 years.
As steam vapor travels up the column, the essential oil vapors and the floral water vapors rise to the highest point and then are run through the condenser and cooled down. This drop in temperature converts the vapor back into liquid form and the hydrosol/floral waters are collected and then decanted (separated). In direct steam distillation, the herbs are suspended in the vapor (steam) path in a botanical basket, which is commonly referred to as a “Gin Basket.” The floral waters are collected (decanted) from the bottom outlet and the essential oils are decanted from the upper outlet.
When using any of the distillation methods, the liquid coming off the condenser is a combination of these two distinct parts consisting of the essential oils and the hydrosol or floral waters.
Simple Crock Pot Water Distillation Recipe
- Crock pot with lid
- Pure water
- Enough fresh plant material to fill the crock pot about half full (about 3-4 cups)
- Mason jars with lids (you will need at least two of these)
- Small dark-colored bottle (for storage)
Instructions
1. Chop up and place the plant material in the crock pot and cover with water. Have the water fill no more than 3/4 of the column of the crock pot, it needs some air space at the top.
2. Put the lid on upside down. The concave structure will allow any steam that forms to condense and fall back into the pot. Sometimes, you can substitute an inverted plate to accomplish the same as the crock pot’s lid.
3. After the plant material has cooked on low for at least four hours, or up to 24 to 26 hours if you wish for a better extraction rate, turn it off and let it cool down. After it has cooled, place it inside a refrigerator and leave overnight, or for a day or two.
4. Remove the pot from the refrigerator and you’ll notice that there is a thin film of oil on the top and should be hard after cooling. This is your essential oil!
5. Quickly and carefully, lift the oil off of the water, and place it in a small, dark-colored glass jar. There may be a small amount of water-based liquid on the bottom after it melts which can be removed by simmering overheat for a short time. Don’t heat the oil for too long as it will lose some potency if it’s left too long. You can also leave the lid off for a while, letting some of the water evaporate.
From this recipe, you will only get a teaspoon or 2 of essential oil from the 3 to 4 cups of plant materials.
As an alternative, you can do this above procedure on your stovetop using a large pot with a lid. Place the plant material in a mesh bag and simmer for at least 24 hours, adding more water if needed. Repeat the above instructions for separating the essential oil. Make sure the lid is inverted so the steam vapors can condense and drip back into the pot.
Freezing Extraction Recipe
This method uses ethanol as the solvent to first make a tincture, and then the ethanol is removed by freezing, leaving behind just the plant’s essence as an essential oil. When using ethanol to extract the medicinal properties from the plant material, you first macerate the herbs for three to six weeks. Then the mixture is frozen.
You will be left with a frozen layer of essential oils and plant material, and a layer of ethanol that doesn’t freeze when it is greater than 80 proof at normal freezer temperatures. Remove the jar from the freezer and skim off the top of anything that is floating and quickly strain off the liquid ethanol into a receiving container or jar for reuse. This needs to be done quickly, as the frozen mixture starts to warm up it will carry some of the essential oils off.
- 1-plus cup dried flowers and/or plant parts
- 80-120 proof ethanol (vodka, rum, etc.)
- Mason jars with lids (you will need at least two of these)
- Cheesecloth
- Small glass or stainless steel bowls (you will need at least two of these)
- Spoon
- Medicine eyedropper, pipette, turkey baster or a drinking straw
- Small dark-colored bottle (for storage)
1. Dry out the plant material that you intend to use. If using flowers, dry them out until they look like they are starting to wilt.
2. Fill jar with the dried herbal material.
3. Pour the ethanol into the jar until the plant material is completely submerged, and leave about 1/2 inch to 1 inch of air space on top.
4. Replace the cover securely, then give the jar a good shake and store it in a dark place, like the corner of a cabinet or a closet.
5. Shake the jars at least one time a day and let this tincture age up to six weeks.
6. Strain off the plant material through the cheesecloth, which you can place in a strainer to support it and make it easier to press out the remaining liquid with a wooden spoon. Avoid spilling any, as this is what now contains the plant’s essence. Squeeze the cheesecloth to get the last drops out. You can also use a fruit press to squeeze out the remaining amount of ethanol.
7. If you wish for a stronger and more potent final product, you can repeat this process several times using new and/or different herbs with the same ethanol increasing the final amount of essential oils extracted.
8. Once you have completed the soaking/straining process, strain it off one final time into a clean quart Mason jar. Replace the cover tightly and store again in a dark spot for two to five days undisturbed. You’ll notice the ethanol will start to separate from the essential oils and other plant matter.
9. Place this jar into the freezer and wait until you are left with a frozen layer of essential oils and plant material and a layer of ethanol, which doesn’t freeze when it is above 80 proof.
10. Now you will need an additional bowl, a second Mason jar, a stainless steel spoon, the medicine eye dropper and a small dark-colored glass to store the essential oils.
11. Remove the jar from the freezer, uncover and skim off anything floating on top and place on the cheesecloth that is laying on the bottom of the first bowl.
12. Secure a piece of cheesecloth to the top of the Mason jar. You can use the Mason jar’s screw-on outer ring to hold in its place.
13. Quickly pour off the ethanol that didn’t freeze through another piece of cheesecloth into another Mason jar.
14. Pick out any frozen bits and place them into the small, colored glass bottle. These are the essential oils and at room temperature will return to their liquid state.
NOTE: If you cannot get access to an eyedropper, pipette or turkey baster, you can use a common household drinking straw. Place one end of the straw into the essential oil layer and then placed your thumb on the other end of the straw, lift and place in the receiving container. Let go with your thumb and the essential oils will drop into the collecting container.
