Thursday, March 09, 2006

Carrier Oils, Essential Oils, Hydrosols (Aromatherapy/Natural Skin Care)

One thing that confuses people about aromatherapy and natural skin care is some of the terminology. Since I've posted a lot about carrier oils, essential oils, and hydrosols, I've finally decided to distinguish them below.

What is a carrier oil?

Carrier oils are just another name for any vegetable, nut, or seed (fatty) oil that is used in aromatherapy and natural skin care. They are called "carrier" oils because they are the oils that are used to dilute essential oils; the "carriers" or base of the blend. They are also sometimes called base oils. Examples include: olive, jojoba, and apricot oils.

A good, in depth explanation may be found at Aromaweb.

What are essential oils?

Though they are termed "oils", they are not greasy, "oily", or fatty, but are highly volatile substances. I've read many definitions from almost 30 books and there is no perfect definition on exactly what they are. What is agreed upon is that they are volatile substances, and that they are generally made of hundreds of chemical components that are responsible for a plant's fragrance as well as disease prevention and insect attraction/repelling activities.

Within the plant, essential oils are stored in special plant cells. Depending on the plant species, these cells can be found in either the leaves, flowers, roots, bark, fruit peel, or seed (fruit). One plant may yield up to several different types of essential oil. For example, neroli (flowers), petitgrain (leaves), and bitter orange (peel) essential oil all come from the same plant: Citrus aurantium, the orange tree. Not all plants have essential oils.

Plant matter is typically steam distilled to produce essential oils, though some (mainly citrus peels) are obtained by expression (pressing), and others (in particularly delicate and expensive flowers) may be extracted by solvents. There is also a new extraction method that involves CO2 that some people consider produces the purest product, though CO2 extracts contain many of the plant's waxes and constitutes not found in other types of essential oils. Since CO2 extraction is such a new method, all of the medicinal and cosmetic benefits of CO2 extracts are not yet known.

Aromaweb also has a great article describing essential oils in detail.

What is a hydrosol?

In the process of creating essential oils (steam distillation), two end products are created: essential oils and hydrosols. Hydrosols, also called flower waters or hydrolates, can be thought of as a distilled herbal water--kind of a fancy way of producing an herbal tea that has many more components than a regular herbal tea, and also contains trace amounts of essential oils. They also have one up on regular herbal teas in that they have a shelf life of 3-4 months rather than days. Popular hydrosols that you may have heard of are rose water and orange flower (neroli) water that are often used in many cosmetic recipes as well in Indian and many Middle Eastern cuisines.

Please note when buying hydrosols that there are two products that are called "flower waters". The other is basically essential oil mixed with distilled water; which is a different product. This type of flower water makes a wonderful all purpose aromatherapy spray, but should NOT be used in cooking. Though I've used the essential oil type of flower water in skin care, I much prefer the true hydrosol for use as a skin toner.

No comments: