Methyl ester of rapeseed is a methyl ester mixture made up of saturated and unsaturated C16 to C22 fatty acids. Technically, methyl esters of rapeseed are produced by chemical conversion of rapeseed oil (colza oil), using methanol.

Chemical conversion of refined rapeseed oil (colza oil) with methanol yields methyl esters of rapeseed in the form of a clear, thin, combustible, non water-soluble liquid that gives off a faint smell. It is used as a substitute for diesel fuel (Biodiesel) but methyl ester of rapeseed is also used as a solvent in the specialist industries (adhesives). The principal constituents of methyl ester of rapeseed are oleic (55-65%), linoleic (18-25%), linolenic (5-11%) and palmitic acids (5-8%). Other fatty acids account for <1% of the product.