T Nation

Canola Oil Processing


#1

Regarding the hate on Canola Oil, I have found the following:

  • Refining/Bleaching/Deodorizing of rapeseed causes oxidation of the n-3 fatty acid content (Apparently mostly the last one)

  • Canola oil gets further oxidized during heat processing (To extract oil from the rapeseeds)

  • There is a high Erucic acid content in unrefined rapeseeds (bad), but canola is also called LEAR oil (Low-erucic acid Rapeseed) oil, as this part has been processed out.

I was also reading up on Nervonic acid, which is apparently a fatty acid found in high concentrations in the brain. Canola was the most significant natural source of this oil.

My question is, are the 'evils' of canola oil solely due to processing and erucic acid? I cannot find anything to imply that erucic acid is a concern anymore, and if one could find cold-pressed canola oil then most the harm would be negated, and the Nervonic acid accrued without harm.

Also, I would imagine with an n-3 content of 10% (from estimates I have read), the deodorization process can't oxidize too much, especially since there are probably anti-oxidants in the oil to negate this.


#2

Although there is such a thing -- hard to find, though -- as high-oleic canola oil, in general canola oil is, relative to most foods and to historically-natural linoleic acid concentrations in the body, very high in linoleic acid.

That would be harmless if only small amounts were consumed, but unfortunately it and other high-linoleic oils have become staples of the American diet.

This actually has resulted in much higher linoleic acid levels in humans.

Historically, I doubt man ate much oil from corn or rapeseed, or any high linoleic source. Sunflower seeds certainly would have been eaten by some at some times, but I doubt they were ever a staple for any major percentage of humanity.


#3

This article sums up everything I think about canola...

http://www.westonaprice.org/The-Great-Con-ola.html


#4

I forgot about n-6s in Canola, thanks for that.

That 'hard to find' high oleic acid canola oil, does the increased percentage of oleic come at the cost of linoleic acid? If wikipedia is to be trusted than regular canola would be 61% oleic and 21% linoleic.

Although if 'oleic' is actually oleic rather than a more marketable 'Omega-9', then my inquiry as to a source of nervonic acid is moot. :frowning:


#5

I'm not familiar with high-oleic canola oil and have never myself seen it for sale: I mentioned it to avoid the inaccuracy of tarring all canola oil with the high-linoleic label.

Yes, the linoleic acid content is lower in the high-oleic product.


#6

I searched here:

http://www.nal.usda.gov/fnic/foodcomp/search/

Looks like standard canola oil is 60% oleic, while it lists Natreon high oleic as 70% oleic. (olive oil is like 70%, and safflower is 74%)


#7

Thank you!

I really should have done that myself.

The difference in linoleic acid content between the two is less than I had thought: about 14% vs 18%, and both are lower than I had thought.

Still higher than I prefer myself, and higher than say grass-fed beef or olive oil, but not as extreme as some other vegetable oils.


#8

I just picked some canola up at the store, here's why:

  • Olive doesn't do well at high temps. And sometimes you don't want things to taste like olives.
  • Coconut oil sometimes turns solid undesirably, and tastes like coconuts.
  • Safflower (or avocado, or macadamia, or whatever) was just too expensive, considering I'd probably be using it infrequently, but in highish quantities.

But that's from more of a cooking perspective than an agribusiness-hatin' perspective.