Rapeseed has a uniquely low content of saturated fatty acids and a high content of monounsaturated fatty acids. It is also a rich source of n-3 fatty acids (linolenic acid) in the diet. Based on its nutritionally well balanced composition rapeseed oil has taken the place of soyabean or sunfl ower oil in many applications e.g. in mayonnaise, dressings and as a liquid component in margarines and spreads. The use of rapeseed oil methyl esters as a substitute for diesel fuel takes increasing volumes of rapeseed oil. Within EU 50 % of rapeseed production was used for biodiesel 2006. A small but increasing proportion is used for technical purposes, for example as lubricating oil for chain saws and in hydraulic oils for the forestry industry to offer a bio-degradable alternative to mineral oil based lubricants. A special type of rapeseed oil with high content of erucic acid (HEAR) is used in a range of non food applications.
Rapeseed has become the special oil plant of Northern Europe. Outside Europe the dominant producers are China, India, Canada and Australia. Rapeseed is planted either in the autumn (winter varieties) or in the spring (summer varieties). As the oil content of rapeseed is 40-45 % the processing is made in two steps – prepressing plus solvent extraction – or only by pressing. The rapeseed meal is an important protein source in compound feed for cattle, pigs and poultry.