The rapeseed plant, Brassica napus, is a member of the mustard and cabbage family, Brassicaceae, and one of the world’s most significant oilseed crops. Recognized for its yellow flowers that bloom in vast fields, the plant can reach heights of up to five feet. It has smooth, bluish-green leaves and develops elongated pods containing oil-rich seeds.
From Rapeseed to Canola
The distinction between rapeseed and canola comes from agricultural science. Traditional rapeseed oil contains high levels of erucic acid, which raised health concerns. The plant also contains glucosinolates, compounds that gave the leftover meal a bitter taste, making it unsuitable for animal feed. These traits limited the original plant’s use for consumption.
In the 1960s and 1970s, Canadian scientists Drs. Keith Downey and Baldur Stefansson addressed this through selective breeding. Their work lowered the concentrations of both erucic acid and glucosinolates, creating a more versatile and palatable product.
To differentiate this improved crop, the name “canola” was created in 1978 as a portmanteau of “Canadian oil, low acid”. International standards define canola as containing less than 2% erucic acid and minimal glucosinolates. While all canola is a type of rapeseed, only rapeseed varieties meeting these criteria can be called canola.
Agricultural Cultivation
Rapeseed is cultivated worldwide, with Canada, the European Union, and China as the largest producers. The plant is adaptable to a range of well-drained soils and grows well in temperate climates, making it a viable crop across many agricultural zones.
Farmers cultivate two main types: winter and spring varieties. Winter rapeseed is sown in autumn and develops a leafy rosette that stays low to the ground through winter, a process called vernalization that is necessary for flowering. Spring varieties are planted in spring and complete their life cycle in one growing season. This allows for flexible planting schedules based on regional climates.
Diverse Applications of Rapeseed
The uses of the rapeseed plant are varied, based on the chemical profiles of traditional and canola-grade varieties. Canola oil is a staple in kitchens due to its neutral flavor and high smoke point, making it suitable for frying and baking. It is a common source for cooking oils, margarines, and salad dressings.
Industrial rapeseed oil is used for non-food applications. This traditional oil is used to manufacture biodiesel, a renewable energy source. It is also used as a lubricant for machinery and jet engines and in the production of soap and hydraulic fluids.
After oil is extracted from the seeds, the remaining solid material is called seed meal. Canola meal is a high-protein byproduct used as animal feed for livestock, poultry, and fish. The meal from industrial rapeseed has more limited use in feed due to its higher glucosinolate content.