What are essential oils?
Essential oils are the concentrated, volatile, aromatic compounds of a plant.
The plant’s primary aromatic features (its leaves, flowers, and roots) go through a steam distillation process to extract the oil. The liquid that distills off is considered the plant’s essence, while the smaller amount of liquid that remains is the essential oil.
Essential oils are highly concentrated, very volatile, and much stronger in aroma. (It takes 250 pounds of fresh peppermint to produce one pound of peppermint essential oil!) Because essential oils are so highly concentrated, they need to be diluted in order to be safe and effective on the skin.
It’s important to note that even diluted essential oils can still be allergenic or irritating to hyper-sensitive skin types. Essential oils also tend to have potent antibacterial, antifungal, and antiviral properties because of their highly concentrated form.
What Are Extracts？
Extracts of plants through cold-pressing or soaking a plant (typically in water, oil, or alcohol) to create a tincture-type liquid. Extracts are similar to making tea, they’re infusions to reach a concentrated, liquid form of the plant.
While their benefits may not be as concentrated as essential oils, extracts can be used in higher quantities and tend to be gentler on the skin, while still providing the benefits of the plants from which they are derived.
In addition, the study Essential Oils and Herbal Extracts as Antimicrobial Agents in Cosmetic Emulsion reveals that extracts and essential oils…can be recommended as effective candidates for natural cosmetic preservatives.
Both essential oils and extracts provide wonderful aromatherapy benefits. Each is a plant extraction of some sort, and each serves wonderful (albeit different) purposes in skincare.
What’s the difference between essential oils and extracts?
First, you need to thoroughly understand that there is a difference between essential oils and extracts. Although both are used in natural skincare and mostly in aromatherapy, there are significant facts that you need to know. How are essential oils and extracts prepared, how effective are they, and do all plants have essential oils?
Essential oils VS extracts – how effective?
The preparation of essential oils is way more complicated than the preparation of Botanical Extracts. There are studies suggesting that essential oils are more potent and stronger than extracts. This is why these essential oils and Botanical Extracts do not have the same effects on your skin.
While essential oils may be stronger and more effective, this also means that sometimes essential oils can have more impact on your skin. Some essential oils need to be diluted before use as a skin care treatment due to their high potency.
However, this does not mean that extracts are not effective. In fact, extracts have a major role in keeping your skin healthy without worrying about how strong they are for the skin. At the end of the day, it is your skin type that will determine the effectiveness of these best essential oils and extracts.
Plants with no essential oils
It is important that you also understand that not all plants contain essential oils. However, this does not indicate that the plant with no essential oil has no use at all because its extracts can still be used. There are also plants that contain such a small amount of essential oil that is not cost-effective to gather it through distillation.
On the contrary, there are also other methods used in gaining essential oils from the plant with a small amount. Enfleurage, a process wherein fats are used to collect the essential oils (also called absolutes when this process is used) from these types of plants, can be done. However, this is more expensive and not a reasonable way to gain essential oils.
Several plants may not have essential oils, but some of their parts have. For instance, cucumber and watermelon are water-based fruits that do not have essential oils, but their seeds produce oils that can be valuable to one’s health.
Preparation of essential oils and extracts
The first difference between essential oils and extracts is how these are prepared. Botanical Extracts are easy to prepare and do not require a high and excessive amount of plant material during the preparation process. The process of getting Botanical Extracts is more like an infusion wherein plants are soaked in a liquid to isolate the needed plant extract.
On the other hand, the preparation of essential oils is quite complex that requires a high amount of plant materials. Essential oils are obtained through the preparation process called distillation with the help of steam.
Throughout the process, plant essence or liquid will be distilled off and only a small amount of liquid will be left behind, which is the essential oil.
Essential Oil Extraction Methods
- Solvent Extraction
This modern method implements food-grade solvents such as ethanol, benzene, dimethyl, or hexane to isolate the oils. It’s often used for extracting essential oils from delicate aromatics, such as jasmine or rose, which are generally unable to withstand the pressure of steam distillation.
Plus, solvent extraction typically produces a finer fragrance than most other extraction methods which further adds to its appeal for certain applications.
Solvent-based extraction can use ethanol, methanol, or any of several petroleum-based hydrocarbon solvents, including Hexane, Pentane, and Acetone.
The solvent, selected for its affinity with the desired plant compounds, flows through the prepared biomass to penetrate the plant structures and release the essential oils.
The resulting mixture of solvent, plant oils, and botanical solids is typically filtered and vacuum distilled to remove as much solvent as possible, especially when petroleum-based hydrocarbons are used. A small percentage of chemical solvent residue can remain in the final product.
- Steam Distillation
Steam distillation is the most commonly implemented method of essential oil extraction. Simply put, steam distillation of essential oils works by passing hot steam through raw plant materials. The heat from the steam serves to vaporize the plant material’s volatile compounds.
The vaporized compounds rise and enter a cooling chamber, known as a condenser unit. As the vapors cool, they’re condensed from steam back into a liquid form.
After being condensed, the essential oil and water from the water-soluble parts of the plant—known as hydrosols or floral water—are collected into a receiver with two separate outflows. Because oil and water don’t mix, the essential oil floats above the water. As such, the lower outflow will draw out the water and the upper outflow will draw out the essential oil.
Part of the reason why steam distillation is such a popular process of extracting essential oils is that the volatile compounds can be distilled at temperatures that are lower than their boiling points.
As such, the natural qualities of the plant material are less likely to become altered or diminished during the process. For this reason, essential oil distillation is often regarded as the only extraction method that allows for purity.
- Expression (Cold-Press Extraction)
Expression, or cold-press extraction, is typically used for isolating oils from citrus peels. This ancient essential oil extraction process originally involved soaking citrus peels in warm water and then hand-squeezing them with a sponge until the oil glands burst.
Once the oil was released, it was collected in the sponge and squeezed into a collection container where the juice and oils would separate over time. Today, the process of expression is a bit more technical and involves the use of machinery.
The modern expression process involves the use of a device that punctures the citrus peels so the oil sacs on the underside of the rind rupture. Once this happens, the oil runs down into the device’s collection area.
Then, the peels are mechanically pressed to squeeze out all of the oils and juices. At this point, resulting oils and juices will still contain the peel and other solid elements of the fruit which must be centrifuged to separate the liquids from the solids. The oil will then separate from the juice layer to create the final essential oil product.
- CO₂ Extraction
CO₂ extraction is a type of essential oil extraction that uses carbon dioxide as the solvent. Unlike traditional solvent extraction, however, no residue is left behind which generally makes the resulting oils purer and safer for use.
The process of CO₂ extraction starts by pressurizing the CO₂ until it liquefies. The liquid CO₂ is used as the solvent to extract the oils from the plant material. Once the CO₂ has absorbed the essential oil, the extract is returned to regular pressure which causes the CO₂ to revert back into a gas.
As a result, there isn’t any residual solvent that gets left behind in the extracted oil. Plus, CO₂ is colorless, odorless, flavorless, and non-toxic; it won’t impact the resulting oil.
However, because CO₂ extraction takes place in a completely sealed chamber, it recovers the whole oil from the plant material—including any pesticide residue. Thus, the resulting oil may have a greater amount of pesticides in it than other conventional extraction methods.
Extract preparation method
At present, the common methods for extracting Botanical Extracts include solvent extraction, ultrasonic extraction, microwave extraction, and enzyme extraction.
- Solvent extraction method
Use solvents to extract active ingredients from solid raw materials, and the solvents used must have the characteristics of miscibility with the extracted solutes. After crushing the plant material, put it into a suitable container, add several times the amount of solvent, and extract it by dipping, percolating, decocting, refluxing, and continuous extraction.
During the extraction process of the solvent extraction method, the concentration of the solvent, the ratio of solid to liquid, the extraction temperature, and the extraction time will directly affect the extraction rate of the active ingredient.
- Ultrasonic extraction method
The strong vibration and cavitation effect generated by ultrasonic waves accelerate the release, diffusion, and dissolution of substances in plant cells into the solvent while keeping the structure and biological activity of the extracted substances unchanged.
For most components, the ultrasonic extraction method can greatly shorten the extraction time compared with the conventional solvent extraction, consume less solvent, and have a high extraction rate, so it has a higher extraction efficiency. In the ultrasonic extraction process, the selection and concentration of solvent, the ratio of solid to liquid, the extraction temperature, and the extraction time will directly affect the extraction rate.
Compared with the commonly used organic solvent extraction method, the ultrasonic extraction method not only has a high extraction rate, fast speed, and high efficiency but also extracts at room temperature without heating and saves energy.
- Microwave extraction method
Microwave-assisted extraction is a method of selectively extracting the target components in the material by using the characteristics of microwave heating. By adjusting the parameters of the microwave, the target components can be effectively heated to facilitate the extraction and separation of the target components.
The extraction speed of the microwave-assisted extraction method is much faster than that of the traditional method, and the valuable Botanical Extracts are avoided from being damaged and degraded while reducing the extraction time. However, the microwave-assisted extraction method is selectively internally heated and requires treatment.
The material has good water absorption, in other words, the position where the product is separated is easy to absorb water, otherwise, it is difficult for the cells to absorb enough microwaves to destroy themselves, and the product is difficult to release quickly.
For liquid extraction systems, solvent substances are required to be polar, and non-polar solvents are not sensitive to the action of microwaves.
- Enzyme extraction method
The cell walls of natural plants are composed of cellulose, and the active ingredients of plants are often wrapped in the cell walls. Enzyme extraction is a method that uses cellulase, pectinase, protease, etc. (mainly cellulase) to destroy the cell walls of plants, so as to promote the maximum dissolution and separation of plant active ingredients.
In the extraction process of enzyme extraction, the selection of enzyme, enzyme concentration, pH value, enzymatic hydrolysis temperature, and enzymatic hydrolysis time will all affect the extraction rate of Botanical Extracts.
Common Skin Care Essential Oils and Extracts
Frankincense Oil
Research has shown that this ancient oil can reduce the appearance of scars and stretch marks, and it seems to have the same effect on wrinkles and fine lines, according to a paper in Dermatologic Therapy.
In that study, researchers instructed study subjects to apply frankincense oil to one side of their face for thirty days. The treated side showed significant improvement in sun damage, skin texture, and fine lines as well as an increase in skin elasticity.
The secret behind its effectiveness is likely its inflammation-fighting ability. Mix two to three drops of the oil with equal parts coconut or jojoba oil and apply it to your skin.
Rose Essential Oil and Extracts
Let us start with the ever-famous flower rose. It is no secret that a rose, with its beauty and fragrance, brings “joy” and “love” to people. Little did you know; the rose is more than just the flower to celebrate love, but is also the flower that can celebrate skin.
Both the essential oils and the extracts produced from roses are beneficial to the skin. Rose oil and rose extract contain healing properties. A recent study suggests that rose essential oil can destroy acne-causing bacteria. Another study backed this when they discovered that rose essential oil can improve skin permeation.
Rose extracts, on the other hand, are known for their intense hydrating properties. With the help of antioxidants, minerals, and vitamin components, rose extracts bring hydration to the skin and soothe any irritation.
Lavender essential oil
When you think of the aroma of calmness, lavender might be the plant that you have in mind. Luckily, lavender flowers produce a large amount of lavender essential oil that can help in skin restoration.
For skincare, lavender essential oil plays a great part in treating acne and inflammation, just like rose essential oil. The lavender essential oil can prevent and hinder the growth of the bacteria that caused the initial infection. Because of its antimicrobial properties, the lavender essential oil can also be used in cleaning cuts and scrapes on the skin.
In addition to its ability to hinder the growth of bacteria and stop infection, a lavender essential oil also plays an important role in healing and lightening scars. Aside from that, the scent of lavender is known for yielding a calm feeling and lavender essential oil can also calm down stressed skin.
Ylang Ylang Essential Oil
Aside from the sweet scent of ylang-ylang, you will never guess how many health benefits its essential oil can give. However, let us set our focus on how it helps in skin care and treatments. Just like lavender essential oil, ylang-ylang essential oil lifts mood through its calming effect, which has even been noted to lower blood pressure.
Just like any other essential oil with healing properties, ylang-ylang essential oil is used in steam facials to refresh the skin and give a healthy glow. Aside from treating acne, it also balances oily-prone skin. Ylang-ylang stimulates cell growth that enables the user to avoid wrinkles and other effects of skin aging.
Chamomile Essential Oil
Chamomile is used in aromatherapy as a way of fighting anxiety, depression, and sleep disorders. You may already know that chamomile flowers are used to produce stress-reducing teas that can give you comfort and calm whenever you feel stress and pressure. Since chamomile is a natural herb, its uses do not just stop in teas.
Essential oils can also be gained from the chamomile plant. In fact, chamomile essential oil brings numerous health benefits, more than you can imagine. Deep skin care is possible with this essential oil. Studies indicate that chamomile contains inflammation-fighting flavonoids that can reduce inflammation in the skin.
Chamomile essential oil is also used in fighting free radicals, which are responsible for skin aging. On top of that, it is also proven that products containing chamomile essential oil and extract can treat eczema and other skin diseases.
Green Tea Extract
Green tea has long been known for its anti-inflammatory properties. Owing to its high catechins content, green tea extract is able to soothe and calm the skin. It is also chock full of antioxidants, each of which offers its own benefit to the skin.
First, there’s vitamin B, which promotes collagen production, keeping skin youthful and firm. Next, there’s vitamin E, which hydrates and nourishes the skin. Finally, green tea extract contains another unique antioxidant known as epigallocatechin gallate or EGCG.
Research has shown that EGCG stimulates the production of skin cells and even has the power to rejuvenate dying skin cells.
Cucumber Fruit Extract
The first and most important benefit of cucumber fruit extract is its ability to hydrate the skin because of its polysaccharides component. Polysaccharides are responsible for attracting and keeping moisture in the skin and reinforcing the skin’s own moisture barrier.
Just like how cucumber fruit cools, soothes, and tightens whenever you use slices of the fruit over your eyes, cucumber fruit extract is also responsible for calming the skin.
The cooling effect (which comes from the combination of astringent and anti-inflammatory properties) can help contract large pores, which helps to reduce bacteria building up inside those pores, and as such, can help prevent acne breakouts.
Watermelon Extract
Although only watermelon seeds have oils, watermelon also produces extracts that are beneficial to the skin. More than just a delicious fruit that almost everybody loves, watermelon extract can moisturize, cleanse, exfoliate the skin, and promote cell regeneration. Watermelon extract is rich in vitamin C, amino acids, and other important nutrients that can help treat sunburned skin.
The components of watermelon extract can also treat other skin problems and irritations, such as but not limited to eczema, atopic dermatitis, and premature wrinkles. Watermelon is so nutritious that it is helpful for preventing acne, promoting elasticity of the skin, and slowing down skin aging.
Benefits of Using Skin Oils and Extracts
Benefits of Using Skin Oils
Oils, in general, can be considered more potent than extracts, which can deliver more results when compared to the same ingredient in an extract form.
According to Joshua Ross, a celebrity esthetician and founder of SkinLab, oils can treat a variety of concerns because they mimic the skin’s natural oils. Some of the benefits of plant oils are they can help reduce dryness, redness, eczema, psoriasis, and scalp issues, and improve the skin’s lipid barrier. In general, most oils are safe on the skin and all skin types.
Benefits of Using Extracts
Plant-derived extracts are primarily used in skin care for their antioxidant, anti-inflammatory, and antimicrobial properties. Botanical Extracts have the additional benefit of smelling great and feeling good on the skin.
For example, aloe extract is soothing when applied to irritated or abraded skin, and other extracts such as green tea, chamomile, and soy extracts are popular ingredients in many major brands because they may have medicinal effects.
