Re: How do you extract oil from plants?

There are two general ways to extract oils from plant sources: pressing and 
solvent extraction. Since olive and other seeds are often extracted by pressing, 
it may be possible to identify devices that would let you do this in the privacy 
of your own home. However, my search of the WWW has not turned up such a source. 
You may want to contact one of the producer associations (eg, olive farmers) to 
see if they can give you more specific information. You may have more technical 
challenge in extracting oils which are volatile, but they would have the 
advantage that they could be released from the source material simply by 
heating.

Plant oils are generally used by plants to store energy and provide protection 
from evaporative water loss. In general they are more unsaturated (have one or 
more double carbon bonds) than animal oils which tend to be unsaturated.
 
There is an active business in processing vegetable oils and seed oils. I have 
included several links:

Interesting question. Oils and similar substances have fascinating chemistry. 
The chemistry is closely related to cell membrane chemistry.

David Winsemius, MD