Rapeseed (Canola) Oil
The seed oil of Brassica napus or B. campestris (previously described as colza oil) was typically rich in erucic acid (22:1), and the seed meal had an undesirably high level of glucosinolates. These components reduced the value of both the oil and the protein meal but both have been bred out of modern rapeseed, which is now known as canola, double zero rapeseed oil, or low-erucic rapeseed oil. There is still a limited demand for high-erucic rapeseed oil, generally grown under contract as an identity-preserved crop, and used for production of erucamide, which is an essential component of polythene wrapping film. Rapeseed (of all kinds) is now the third largest source of oil, at ~24 million tonnes a year, after soybean oil and palm oil. It is grown mainly in Western Europe, China, Canada (where the canola varieties were developed), and India. Typically it contains palmitic (4%), stearic (2%), oleic (62%), linoleic (22%), and linolenic (10%) acids and has less total saturated acid than any other commodity oil. In one example its major triacylglycerols were: OOO (22%), LOO (22%), LnOO (10%), LLO (9%), and LnLO (8%).
Rapeseed oil lends itself to genetic modification and several rapeseed varieties having oils with modified fatty acid composition have been developed though it is still not clear how many of these will be economically viable. Rapeseed oils with less linolenic acid, with enhanced levels of lauric acid, stearic acid, oleic acid, or with unusual acids such as γ-linolenic acid, ricinoleic acid, or vernolic acid have all been developed for commercial exploitation. An oleic-rich variety developed in Australia, called Monola, contains about 78% oleic acid.