Methods of Essential Oil Extraction
There are many methods of essential oil extraction and the methods used depend on the type of plant as well as the type of oil that is produced. Some essential oil extraction methods are better than others and produce very pure essential oils. The purer the oil the more difficult the process is and the more expensive the resulting oil is.
Understanding the extraction process can help you determine what essential oils to buy and which ones to avoid. Some essential oil extraction methods can not only produce poor oils but also cause allergies even if the oils produced are cheaper.
Steam Distillation
This is a common method of essential oil extraction but it is currently not the best method as there are new methods that are being developed. However pure essential oils produced with this method are of a good quality. The plant, whether the leaves or roots, are placed into a still and pressurized steam goes through the plant.
The oil inside the plant reacts with the steam and bursts and evaporates. The evaporated essential oil passes through the top of the still with the steam into a water-cooled pipe and is condensed back into liquid form. This method is costly as although millions of a particular plant it results in a comparatively small amount of essential oil.
Maceration
Maceration does not really produce essential oils as it involves the use of carrier oils. Oil that results from maceration can be used directly on the skin unlike essential oils. This method involves soaking the plant in carrier oil and then heating it up. The oil is then strained and it is ready for use. Typically this method is used to produce massage oils that have been infused with a specific plant or herb.
Cold Pressing
Cold pressing is the essential oil extraction method used primarily for citrus oils and anything else that has a rind. Only the rinds of the fruit, such as lemon, orange, grapefruit and bergamot, are used in this method. The rinds are either cut up finely or ground and then pressed. Essential oil does not immediately result, instead there is a mix of essential oil and liquid that will eventually separate.
The process is longer than steam distillation. Citrus essential oils and oils produced this way are notoriously volatile and prone to oxidization. So only buy as much as you will use in the next six months or you will have bottles of useless oil.
