Seeds, sometimes reduced in size, or cake remaining after pressing are extracted with industrial hexane (a mixture of hexane and methylpentane). Solvent is recovered for re-use but some is lost in the oil (~ 2 litres/tonne) and in the meal (~ 8–10 litres/tonne).
M.A. Williams, Lipid Technologies and Applications (ed. F.D. Gunstone and F.B. Padley) Marcel Dekker, New York (1997), pp.113-135. J.-M. Fils, Edible Oil Processing (eds W. Hamm and R.J. Hamilton), Sheffield Academic Press, Sheffield (2000), pp.47-78.