Brassica species are cultivated since historic times, particularly in Asian countries. According to ancient Indian literature, cultivation of B. rapa was practiced since 1500 BC and seed of B. juncea was believed to be found in archaeological sites dating back to 2300 BC. On the other hand, the Chinese word for rapeseed was first recorded 2500 years ago, and the oldest archaeological discoveries reported to be dated back to 5000 BC.
Rapeseed oil reported to be used as a marine and industrial lubricant during World War II and consequently, the market for rapeseed oil plummeted in the post war period. Production of rapeseed has been rising rather steeply during the past two decades and has outpaced the production of other oilseeds including peanut, cottonseed and sunflower.
Composition
Well-developed rapeseed seed contains 40 to 44 per cent oil. Present day cultivated varieties contain only traces of erucic acid, 5 to 8 per cent of saturated fat, 60 to 65 per cent of monounsaturated fats, and 30 to 35 per cent of polyunsaturated fats. Recently developed strains, several lines were identified having high oleic acid (60 to 70 per cent), moderate to high linoleic (9 to 38 per cent) and low linolenic acid (4 to 7 per cent) content.
