If you’ve ever wondered how essential oils are made, you’re not alone. Most people have heard about the different ways that they can be produced, but very few understand exactly what they are made from. It’s important to know what they are, and why they’re used in order to make an informed decision about what you’re buying.
Steam distillation
Steam distillation is one of the most common methods used to produce essential oils. It is a relatively inexpensive method of generating organic solvent free oil.
The process begins with plant material that is immersed in water in a Still. During the heating process, volatile aromatic compounds from the plants escape. These compounds are then collected and separated into two liquids. A liquid called hydrosol is produced, while the remaining water is known as floral water or herbal water.
Steam distillation is the most popular way of extracting essential oils. However, it is not the only method available. Other methods of extraction include expression and solvent extraction.
Essential oils are multi-component chemicals that contain polar and non-polar molecules. In order to separate an essential oil, the polar constituents are separated from the non-polar ones.
Steam distillation is a fairly straightforward process, but it requires careful attention to detail and careful control of temperature and time. It also uses equipment that is relatively inexpensive.
Typical temperatures for steam distillation are 140 to 212 degrees Fahrenheit. This low temperature reduces the potential damage to heat-sensitive components. Depending on the type of plant being distilled, the final product may be either a water-insoluble liquid or a water-soluble hydrosol.
Steam distillation is a highly effective and scalable method of producing essential oils. It is ideal for the production of heat-sensitive essential oils.
Expression
The expression process is a method of producing pure essential oils. It involves a machine-controlled technique that uses the outer skin of a citrus fruit.
After the peel has been cut, a rasping cylinder runs across the surface, breaking open small oil sacs. These are then collected in a device. Oil is then sucked out and the juice is separated.
Essential oils are an aromatic volatile substance produced by plants. They contain hundreds of organic constituents. Many of these molecules have beneficial properties when ingested. In addition, they also have a strong antimicrobial activity. This characteristic odor enables essential oils to repel predators and discourage competitive species from growing near the plant.
The expression method can be used to extract many different base oils. However, it’s best for extracting citrus peel oils. Other types of plants can be extracted by one of several other methods.
Another way to produce pure essential oils is with a process called solvent extraction. During this process, the oils are filtered through food-grade solvents.
Steam distillation is another common method for extracting essential oils. This method is often used for delicate aromatics. During steam distillation, volatile compounds in plant materials are vaporized. These vapors are then condensed in a cooling chamber known as a condenser unit.
In contrast to distillation, the expression method does not involve a heat source. Instead, it uses high mechanical pressure to squeeze out the oil from the material.
Hexane/dimethyl ether
One of the best ways to extract essential oils from plants is through the use of liquid dimethyl ether (DME). This relatively inexpensive solvent has been used in a number of industries, including cosmetics and pharmaceuticals. The DME-enhanced extraction process is comparatively less toxic than its classical counterparts.
Liquid dimethyl ether, the liquid form of n-hexane, is a biodegradable aqueous solvent. It is relatively free from the deleterious properties that plague its solvent cousins, and is readily available in light weight canisters. Dimethyl ether is easily liquefied and has an affinity for water that allows for a high degree of extraction efficiency. Moreover, it has an appealing design that makes it an ideal candidate for a green chemistry lab.
Hexane/dimethyl ether has been found to be the key to unlocking the secrets of plant-derived essential oils. Amongst other things, this solvent is relatively resistant to auto-oxidation and is capable of capturing the non-polar lipids and carbohydrates that are vital to the plant’s health. Another important aspect is that it is synthesized from biomass, thus making it an environmentally friendly option for the extraction of valuable plant chemicals.
A more modern method of extraction using subcritical carbon dioxide has also been embraced, albeit with a caveat. Compared to the DME-enhanced extraction process, the supercritical CO2 method requires a higher initial investment, but yields a larger payoff. In fact, it can be considered the most environmentally responsible alternative to the more expensive classical methods.
Concretes, resinoids, and absolutes
If you are interested in the scent industry, you will most likely be familiar with the terms concretes, resinoids, and absolutes. These are the products of different methods of extraction, and their chemical compositions may vary depending on climate, growing conditions, and season.
Concretes are a mixture of waxes and oil, and are typically semi-solid. They are ideal for producing solid perfumes. Their wax content helps to hold the aroma. However, they are less volatile than essential oils.
Absolutes are a highly concentrated form of aromatic oil derived from the volatile fluids extracted from plants. They have a higher concentration than essential oils and are often thicker.
Resinoid are similar to concretes, but they are produced by extracting resinous materials. They can be either semi-solid or liquid, and differ in their applications.
In order to obtain an essential oil, the plant material must be treated with a solvent. Common solvents include hexane, ethanol, and petroleum ether. Steam distillation is a common method for extracting fragrances, but it is not suitable for some raw materials. Some materials cannot be steam distilled due to their delicate nature.
The two main ways of obtaining an essential oil are by distillation and by extraction with solvents. The process of distillation is the most common way. It is also the easiest and most economical. Various types of essential oils are produced using a number of different techniques, but all involve the use of a solvent.
Chemical make-up of volatile aromatic compounds
There are a large number of essential oils available on the market. They are commonly used in perfumes, soaps and fragrances. Some of them are even used in medical aromatherapy.
The make-up of these volatile aromatic compounds is determined by many factors. Plant type, extraction method and physical conditions are among them.
Often, they are composed of two biosynthetic groups: phenylpropanoids and phloroglucinols. Phloroglucinols are a family of compounds built around a central aromatic ring. Usually they are substituted with an aldehyde or acetyl group.
Phloroglucinols are the most common terpenes found in essential oils. However, they are less common than phenylpropanoids.
The biosynthesis of phenylpropanoids and phenylpropane is known to occur by two routes. One is the glycolytic pathway, and the other is the shikimic acid pathway. Similarly, the biosynthesis of isothiocyanates is accomplished by the glycolytic and shikimic acid pathways.
There are other compounds in essential oils that are classified as volatile organic compounds (VOCs) but not as phenylpropanoids. This class of compounds includes short chain fatty acid esters, but they are rare in essential oils.
Phloroglucinols have been grouped into several subclasses, according to the oxidation character of the hydroxyl groups. These include aldehydes, alcohols, phenols, ethers, methylene dioxides and acids.
Another subclass of phenylpropanoids is the benzene moiety. Most essential oils contain at least some phenylpropanoids, but they are not always in a homogenous group.
Safeness for inhalation and application to the skin
There are a multitude of safety measures that are recommended when it comes to inhaling and applying essential oils. These include observing the label directions and storing your product in a child-resistant container.
Essential oils are quite concentrated, and can be absorbed through the skin. As a result, a single drop can cause toxicity in some people. If applied to the skin, the oil may be able to enter the bloodstream, causing a number of adverse reactions including respiratory problems, pneumonia, and dermatitis.
A good rule of thumb is to avoid applying essential oils directly to the skin, unless the company recommends it. Doing so can be harmful to your health, especially if you’re pregnant or have a weak immune system.
The best way to go about this is to select a high-quality, pure essential oil and dilute it properly. Alternatively, you can try mixing a few drops of the stuff with a carrier oil. Using a carrier oil allows the active compounds in the oil to be absorbed into the body.
The best way to determine the appropriate dosage is to read the label closely. You can also check the manufacturer’s website or talk to a company representative. This information may be limited to specific products, but it can provide a solid foundation for your decision making process.
For example, the CPTG Certified Pure Tested Grade is a great way to go. It’s composed of only natural aromatic compounds from plants, and doesn’t contain protein molecules. In addition, the oil is rigorously tested for potential contaminants and other substances that might prove harmful.