Did you think there was a canola plant? I never gave it much thought.
I mentioned in my biodiesel tutorial that oils which contain tocopherol (Vitamin E) have a longer shelf life than oils that do not contain this natural preservative. I noted that rapeseed oil contains tocopherol... what I didn't say was that canola oil is made from rapeseed. So why don't we just call it rapeseed oil? Blame Canada! I'm joking, but seriously, the word 'canola' was coined in 1978 from 'Canadian oil, low acid'. Canola oil comes from select rapeseed cultivars that produce low erucic acid rapeseed oil and low glucosinolate meal. These cultivars were developed in Canada in the 1970s by Keith Downey and Baldur Stefansson.
Though canola oil is derived from a type of rapeseed, there are some chemical differences. Your basic rapeseed oil is green-colored and has an undesirable flavor, so it isn't used for cooking. Since one of the potential negative health effects which might be associated with canola oil is vitamin E deficiency, I am going to guess either canola oil contains less tocopherol than rapeseed oil or else the tocopherol has a lower bioavailability. However, erucic acid also is associated with rancidity and canola oil contains less erucic acid than normal rapeseed oil.
So, in summary... canola oil is a type of rapeseed oil. Rapeseed oil and biodiesel derived from rapeseed oil have a relatively long shelf life. I do not know for sure whether or not biodiesel from canola oil has a long shelf life.