Essential oils, absolutes, resins, and hydrosols have all undergone a process for extracting the essence of plant materials while maintaining the therapeutic properties of the plant. These are not methods that commonly can be used at home or in a small shop. These methods require vast amounts of plant substances, such as flowers and leaves, which are placed in large distillers, only to produce a small amount of oil. This explains why a bad crop or a rare plant will lead to extremely high prices for an essential oil or hydrosol.
All of these “essences” of plants can be used in diluted form in various bath and beauty products. They come in liquid form and need no preparation other than dilution. You will need to familiarize yourself with the proper ratio for use in products. Most companies that cater to soap makers provide this information on their websites or in written materials.
You are probably already familiar with essential oils, whether you choose to use them or fragrance oils in your products. An essential oil is a liquid that is distilled, typically by steam distillation, from the leaves, flowers, stems, roots, bark, or other parts of a plant. The distillation process allows the “essence” of the plant and its therapeutic qualities to remain intact. Essential oils are highly concentrated and should be used sparingly. Lavender and Tea Tree oil are safe for direct skin contact, but all other essential oils must be diluted before applying to the skin. They are used for both their aroma and their medicinal qualities and can be used in most of your products.
Fragrance oils are artificially created or contain synthetic substances and do not offer the therapeutic benefits that essential oils do. Either manner of scenting your products is perfectly acceptable, but if you are looking for natural ingredients with therapeutic qualities, essential oils would be your choice.
Absolutes and Resins
Absolutes and resins are similar to essential oils. Absolute oils are extracted from flowers, leaves or bark. While essential oils are produced by steam distillation, flowers that are too delicate for this process, such as jasmine or vanilla, are extracted with a solvent, usually alcohol. Absolutes are very concentrated as well. While they do not maintain the qualities of the plant to the extent that essential oils do, they can be used to make perfumes and are soluble in alcohol.
Hydrosols (Floral Waters)
Hydrosols, or floral waters as they are sometimes called, are also produced from steam-distilling plants. They are similar to essential oils but less concentrated. Be careful when you look for hydrosols, as many companies sell essential oil diluted in water and call it a hydrosol or floral water. You want true steam-distilled hydrosols that contain all the beneficial components that essential oils possess, with less concentration. Hydrosols are usually a by-product of essential oil production, but some high quality distillers choose to specialize in making only hydrosols. Since hydrosols are not very concentrated, some can be used directly on the skin, such as rose hydrosol, which makes an excellent facial astringent. Their scent will not hold up well in cold-process soaps, but they are great in lotions and creams.