Essential Oils: The Basics

What are essential oils?

Inside many plants, shrubs, bushes, and trees are concentrated, highly potent, natural compounds called essential oils. They can be found in a variety of parts:

• Roots
• Stems
• Leaves
• Seeds
• Fruits
• Flowers
• Bark

Essential oils give a plant its distinct aroma and are complex substances. A single essential oil may contain anywhere from 80 to 300 or more different chemical constituents.1 Essential oils help the plant itself with infection control, wound healing, protection from environmental conditions, and they even assist with pollination, among other important functions and benefits.2 

Benefits of Essential Oils

In humans, essential oils support the mind and body in many ways, too:3

• Mind: promote relaxation, calm tension and nerves, increase positive feelings, decrease stress
• Immune: support healthy immune function, protect against environmental and seasonal threats
• Cardiovascular: maintain healthy circulation, support healthy respiratory function
• Diet: promote healthy digestion, help reduce occasional stomach upset, and promote healthy metabolism
• Physical Activity: support muscle & joint function, support energy and stamina
• Body Systems: improve skin appearance, soothe occasional skin irritations, provide antioxidants, purify the body’s systems, repel insects 

Extraction Methods

Essential oils are not “made,” but instead, they are extracted from plants. They are essentially the liquefied version of a plant, and they effectively allow its beneficial compounds to reach the bloodstream faster than they would by simply consuming the plant.

There are three main ways that essential oils are extracted from plants. The method of extraction matters because essential oils extracted from the same plant, but using different methods, can result in very different products.

• Steam Distillation
• Expression
• CO2

Steam Distillation

Steam Distillation is the most popular method used to extract and isolate essential oils from plants. This happens when the steam vaporizes the plant material’s volatile compounds, which eventually go through a condensation and collection process. This process generates two products: the essential oil, which contains oil-soluble molecules, and the hydrosol, which contains water-soluble molecules.2 

Fun Fact: Rose water is one of the best known and most widely-used hydrosols worldwide, and the ingredient we use in our Rose Water Toner & Facial Mist! 

Some essential oils smell different from the flowers from which they were obtained because the heat of distillation alters some of the chemicals that give them their distinctive smell.

Expression (a.k.a. Cold-Press Extraction)

Expression is most often used to extract essential oils from citrus fruits. 

1. The whole fruit is placed in a device that mechanically pierces it to rupture the essential oil sacs, which are located on the underside of the rind. The essential oil and pigments run down into the device’s collection area.
2. The whole fruit is pressed to squeeze out the juice and the oil.
3. The oil and juice that are produced still contain solids from the fruits, such as the peel, and must be centrifuged to filter the solids from the liquids.
4. The oil separates from the juice layer and is siphoned off.

Expression does not involve heating; thus, the chemistry of citrus essential oils is not heat-altered and citrus oils smell very similar to the fruits from which they come.4

CO2 Extraction

In CO2 extraction, carbon dioxide is used as a solvent. It is added and eliminated to produce a high-grade extract that is very close to the composition of the natural raw material. C02 extracts are different from distilled oils in that they contain a wider range of the chemical molecules found in the plant material.

1. Pressurized carbon dioxide becomes liquid while remaining in a gaseous state, and is pumped into a chamber filled with plant matter.
2. Because of the liquid properties of the gas, the CO2 functions as a solvent on the natural plant matter, pulling the oils and other substances such as pigment and resin from the plant matter. The essential oil content then dissolves into the liquid CO2.
3. The CO2 is brought back to natural pressure and evaporates back into its gaseous state, while what is left is the resulting oil.

CO2 extracts are usually thicker than their essential oil counterparts and often give off more of the aroma of the natural herb, spice, or plant than distilled essential oil.4 

Quality

Essential oils must be respected. There are a number of ways in which the quality of essential oils can be compromised:2

• Plants: The quality of essential oils can be negatively impacted by the use of pesticides and other chemicals, the variability in altitude, soil conditions, rainfall, and the difficulty of differentiating plant species and varieties.
• Processing: Because of the popularity of essential oils and aromatherapy, there are many products on the market that may not be suitable for therapeutic use. These products may include pure essential oils, but sometimes they are adulterated or diluted.
• Packaging and handling: Chemical degradation can occur with exposure to heat, light, and/or oxygen. Citrus essential oils are especially prone to oxidation.
• Storage: Essential oils should be stored in tightly closed, dark glass containers in a cool place.

Our Commitment 

Please know that we are very intentional in the sourcing of the essential oils that we use in Nourish products.

• We support farmers who have the following certifications: USDA Organic, Non-GMO Verified, Earth Kosher, Fair for Life, Forest Grown, and Zero Waste
• We require that the ingredients we use are third-party tested to ensure that they are free from synthetic chemicals.
• We don't take shortcuts or compromise ingredients to save money.
• We use dark glass containers whenever possible to preserve the integrity of our ingredients, giving you the highest-quality products for the longest period of time.

Next Up
Next week, we’ll learn how to safely and effectively use essential oils.