astor seed oil is extracted by prepressing followed by solvent extraction.

Composition
It is a non-siccative oil and mainly contains :

* 80-87% of ricinoleic acid
* 5-9% of oleic acid
* 6-7% of linoleic acid
* 1-2% of stearic acid
* iodine value : 81-91
* saponification value : 167-187
* melting point : -10 to -12°C
* titer : 2-5°C
* unsaponifiables : < 1%
* density (high) : 0.95-0.97 at 15°C
* viscosity at 20°C : 1000 cps
* viscosity at 100°C : 20 cps

The castor oil plant, Ricinus communis, is a species of flowering plant in the spurge family, Euphorbiaceae. It belongs to a monotypic genus, Ricinus, and subtribe, Ricininae. The evolution of castor and its relation to other species is currently being studied.[1]

Its seed is the castor bean which, despite its name, is not a true bean. Castor is indigenous to the southeastern Mediterranean Basin, Eastern Africa, and India, but is widespread throughout tropical regions (and widely grown elsewhere as an ornamental plant).[2]

Castor seed is the source of castor oil, which has a wide variety of uses. The seeds contain between 40% and 60% oil that is rich in triglycerides, mainly ricinolein. The seed contains ricin, a toxin, which is also present in lower concentrations throughout the plant.