Making your own essential oil

There are three things that affect the yield of essential oils you make with your copper still.

• The size of the column
• The volume of raw material
• The average oil content of the raw material to be used.

The column

The bigger the column, the better! For raw materials extracted by water distillation, the yield is determined by the size of the boiler. Although there are some exceptions to this rule, such as clove tops or coffee beans (see chart below). However, for most raw materials intended for essential oil extraction, column size is crucial to consider when choosing your copper distiller.

The volume

Since the oil content is calculated based on the weight of the commodity, the volume of 1 kg of a commodity determines how much you can put in the column at a time. For example, 1 pound/1 kg of dry eucalyptus leaves takes up 3 to 4 times more space than 1 pound/1 kg of dry rosemary leaves.
To determine the volume of a resource, take a bucket and fill it with the resource of your choice. Next, weigh the contents, the raw material, in the bucket. Once you know how much your commodity weighs, you can calculate the volume.
For example:
4 lb (15L) of lavender flowers has a weight of 6.6 lb/3 kg.
To determine the 1 lb/1 kg volume of this raw material, divide the volume by the weight.
So: 4/6.6 = 0.6 lb (15/5 = 5 kg)
So – 1 pound of lavender flowers takes up 0.6 pounds (5 liters) of volume.
If your raw material contains an average of 2% essential oil, you will get 0.6*0.02=0.012 pounds or 0.42 oz from 1 g of lavender flowers (1000 g *0.02 = 20 g of essential oil).
If you have a column of 0.53 g, you extract 0.53*0.42=0.22 oz from the raw material as in the above example.

The average percentage content of essential oils in raw materials

The essential oil content in 1 lb/1 kg of raw material can range from 350 ml to 0.08 ml – or even less! Below is a chart showing the average percentage of essential oil yield for different types of fresh raw materials. These oil levels are only approximate values. The quality of the raw material affects the exact yield in percentage of essential oil.
‘Wise’ is the preferred way to extract essential oil.

SD for steam distillation
SW for steam and water distillation
SE for solvent extraction
WD for water distillation
CE for cold expression