How come Seed Oils have higher smoke point?

[organicblood]

Quick question, that I couldn‘t find a direct, logical answer to:

How come high-PUFA seed oils (e.g. Canola/Rapeseed or Sunflower) are recommended for frying due to their higher smoke point, as opposed to saturated fats like coconut or even butter?

I thought the entire issue with PUFAs stems from their fragility and propensity to quickly and easily oxidize in the body. But at the same time, they can endure higher temperatures whilst cooking? This seems contradictory to me. Can anyone explain this?

 

[xeliex]

Hi there and welcome. It's a good question and one that I asked myself few years ago. Upon researching the topic further, I found out that smoking point and oxidation vs rancidity are very different things. Smoking point is not an indicator of an oil's stability as commonly thought. If you leave high polyunsaturated oils at room temperature while exposed to oxygen, they will oxidize. A saturated fat on the other hand will not.

What You Need to Know About Cooking With Oils | Yogitrition

web.archive.org

 

[organicblood]

Thank you for the article and response!

TBQH it‘s still confusing to me, esp. since all I have on this topic is this one resource of yours, which does indeed link to some studies. But AFAIK there‘s no single publication mentioned in there, that specifically proves this seemingly paradoxical constellation of high smoke point vs heavy oxidation and rancidness at room temperature...

From what I understand, the article makes the case that one is already cooking with rancid seed oils by the time they‘re heated up, since they‘re so prone to oxidation already at room temperature.

In effect, this would mean that the high smoke point is reached by essentially rancid oil, which by then is already mostly composed of toxins.

EDIT:
I did find another article on the matter for anyone interested: smoke point and oxidation

It goes into great detail explaining the difference of smoke points being attributed to the Glycerol subunit of Triglycerides being broken apart, and the oxidation happening at the unsaturated free fatty acids.