Essential Oils: To find the specific properties and applications of individual essential oils, I recommend visiting a page like AuraCacia’s Rather than list singular properties I would like to talk a bit about using essential oils in your body- and home-products.
What are they? A saleslady at a local herb supply stores told me that all essential oils are three things:
1). Not oils. They do not contain fatty acids, and hence, they are not really oils.
2). Volatile. This is why they are also called ethereal oils.
Essential oils are typically obtained through steam distillation: the plant material is put into a distiller, steam is applied to it, and then the steam breaks down the material picks up the plants’ essential oils, rises, condenses and trickles out a chilled pipe. The liquid that trickles out is then separated (or separates on its own) into a hydrosol (the water) and the essential oils. These oils are often further concentrated and purified. It can take an enormous amount of plant material to extract just a little bit of oil – all depending on the composition of the plant and which part of it you use. Certain flowers, like jasmine, are not steam-distilled at all, but rather, their essences are obtained through a process called solvent extraction (the material is mixed with a solvent, like alcohol, and then the solvent is distilled).
In the past, tender flowers like Jasmine that don’t yield their scent well through heat would be extracted using a cold method called enfleurage. This process consists of layering petals on canvases spread with a hard fat (like tallow, lard or coconut) letting them infuse and then repeating the process until sufficient scent is obtained. The fat is then “washed” of its scent, yielding an absolute. There’s a scene showing this process in the movie (and the book) Le Parfum.
Absolutes are more expensive than essential oils, but you can often buy them diluted with vegetable oils also. So make sure you read your labels. It’s important to get quality oils, but if you don’t have oodles of cash keep that option in mind. The same saleslady advised me that if you are getting an absolute primarily for its scent, then a diluted absolute can be just as effective, because the smell is often still strong.
Where do they come from? Essential oils can be distilled from fruits (mostly citrus), herbs, flowers, trees (leaves, wood and resin), seeds pods (pepper, anise seeds etc.). I find it helpful to consider the plant origin of your essential oils, not only because of their inherent properties but also for creating a scent profile. Be aware that sometimes distributors will call a product an essential oil when it is not. The resin from the Styrax Benzoin tree is one example: often sold as an essential oil when in fact the resin is dissolved in alcohol, as a tincture. I have also mistakenly purchased benzoin “essential oil” believing it to be a tincture but finding it dissolved in a Di Propylene Glycol Base.
Why use them? Each essential oil usually has a host of medicinal properties and uses, and you can use them to complement and/or heighten the existing medicinal properties of your product. Of course, you can create a product just to carry your essential oils (carrier oils), because essential oils cannot be used on their own, or applied directly on the skin, and can never be ingested. Essential oils are naturally antiseptic and many can also be used to prolong (NOT preserve though!) the shelf-life of your product. And of course, they can be used solely for their smell.
I would also like to add that many herbalists don’t consider essential oils to be herbal medicine but drugs. Allow me to paraphrase the grande dame of American herbalism, Susun Weed, on this topic: if you take willow bark to a lab, extract a compound from it, purify and concentrate this compound, bottle it, label it Aspirin and sell it to people, is this a drug or is it herbal medicine? Susun Weed also points out that essential oils can eat through plastic (I can vouch for that) and that there has been studies showing that essential oils can modify mitochondria.
For myself, I believe that essential oils are currently overused and oversold, especially to babies and children. Children and people with sensitive noses will usually flinch when you open a bottle of essential oil, others get headaches, runny noses etc. For this reason, I have chosen to use essential oils very sparingly, and only in my soaps. I never use them in any of my baby products not even the baby soaps, and never in any salves and creams.
How to use and keep them? If you use essential oils in a product make sure to always add it in at the end, after the heating stage. Although the shelf-life of essential oils is long, they should still be kept in dark glass bottles in a dark, cool place. They can go bad. It takes a long time, but it happens. Citrus oils are photosensitive, so never use them for face creams or sunscreen, and keep your oils out of the sun (of course).
Classification: essential oils exist in almost all plants, but in varying degrees and in different parts. Not all plant leaves are fragrant, but sometimes the more fragrant parts can be found elsewhere. One way to find out if a plant produces a lot of essential oils is to rub it between your fingers. With some herbs like rosemary and lavender just brushing up against them will release a cloud of fragrance.
A plant can have medicinal value without having essential oils: the more nutritive and mucilaginous plants are excellent examples. You can also extract plant properties including their essential oils without using extracted purified essential oils. Some examples most people know through cooking, are flavored olive oil, like lemon, rosemary or pepper oil. This method of extraction is called maceration. It will not be as potent as the essential oil, but it will be milder, and of course, also carry other properties of the plant, not just the essential oils, as well as the properties of the carrier oil. In other cases, like floral scents, a better alternative to essential oils might be to buy the hydrosol, also known as distillate.
Usually essential oils are categorized by their chemotype. An essential oil contains the various components of the plant’s chemical composition. Together these components create the plant’s (and consequentially its essential oil) distinctive smell or its perfume if you will. The dominant component determines the oil’s chemotype, and is usually responsible for its smell. The chemotype should be indicated on the bottle. For example, the chemotype of lemon-oil is limonene; the chemotype of lavender is linalool. Limonene is described as smelling strongly of lemon, or citrus, and linalool is described as a spicy floral. Lush uses both of these molecular components heavily in their products and labels them as “existing naturally in essential oils,” which is true. But they are not essential oils, and they have also been identified as possible skin irritants. Just FYI…
Preservatives: When making all-natural body-care products it can be wise to consider adding some type of preservative. Especially if you want to sell your products. Luckily there are lots of preservatives out there now that don’t include formaldehyde or parabens. Vitamin E is often considered a preservative, because it can extend the shelf-life of oils. Because it has its own beneficial properties for the skin, it is a popular additive. But remember, it is not a preservative – it simply keeps your oils from going rancid too quickly. I have had creams go moldy on me after a week, with vitamin E, so keep that in mind.
Grapefruit seed extract (GSE) is an all-natural additive, extracted from the seed of the grapefruit, usually used in combination with other things to prolong the shelf life of a product. Some say it is about as effective as praying… But I’ve had good experiences with it. That said, I would not use as a preservative in any product I mean to sell. The way I understand it, the general shelf life of all-natural products containing water and/or organic matter is about a week, if you keep it in the fridge. Balms and salves that do not contain water will last much, much longer. Think about your food: how long does your olive oil last in the fridge, and how long does homemade fresh basil pesto last? How long does a cup of tea last if you leave it on the counter?
Just like GSE, which is a citrus fruit extraction, citrus oils have antimicrobial properties. As, I mentioned above, limonene is added to almost all of Lush’s products, the ones that don’t contain parabens. This is why I am starting to think that it functions a bit like a preservative. I would just stick to GSE if you are looking for a preservative. If you add lemon oil for its antimicrobial properties, just remember, it is photosensitive, so don’t put it in a day-time face cream, or a body lotion. (the same reason your hair bleaches when sprayed with lemon juice).
Tea tree oil is often used as a preservative due to its antibacterial and anti-fungal properties, but it is not a preservative or an alternative to preservatives. While common uses for tea tree include healing skin problems, like dandruff, eczema, psoriasis etc. tea tree oil is a potential skin sensitizer, so keep this in mind. As a person who suffers from psoriasis I can tell you that topical applications aren’t usually the answer. Life style adjustments tend to work better for wide spread skin issues (less sugar, less processed wheat, kefir, are some of the things that have helped me in the past).
Production: the best way to make sure your product lasts to its full ability, is to work clean. If you are making lotion for yourself, I see no need to go out an buy a whole set of kitchen ware to whip up some body butter. Just clean your workspace, your hands and your tools well. And when your product is done, avoid putting unclean hands in it. Easy! If you are making product for others or to sell, I would suggest getting tools exclusively for your body products.
Storage. A great way to make sure your homemade cosmetic products stay fresh is to store them properly: sealed in clean sterile containers, in a cool, dark place. The fridge might be a good place for surplus creams and lotions.