I haven't tried the safflower oil yet. I'm waiting to try it in a recipe that calls for neutral oil. I figure that other people will notice the flavour of the EVOO more than me, since I use it so much. A lot of people don't think you can fry with it, so they use EVOO a lot less than I do.
I read an article that listed the healthiest fats for frying: ghee, lard, suet or maybe they wrote tallow, EVOO, and coconut oil (or was it palm oil?). I think there were another two animal based fat that I am forgetting. (I vaguely remember it being 7 fats and they made a point of the two veggie based fats being the odd balls.). It discussed how how much better those fats hold up to heat without creating free radicals, than the fats that most people seem to think are better for frying. At least I think it was free radicals. It might have been some other problematic chemical compound. I wish I could remember where I found that article. I have tried looking for it, but haven't been able to find it again.
It's nice to see you taking an interest. Right, yeah there's so many types of evoo and some are more flavorful than others, that for sure. Personally I use evoo a fair amount of the time but only made the mistake of making mayonnaise once with evoo, way too powerful and overbearing.
As far as free radicals go, yeah, seed oils especially the ones high in polyunsaturated fats do that more so than seed oils that have less polyunsaturated fats and oils or fats higher in monounsaturated and saturated fats are the least likely to create free radicals hence less oxidation. For example preserving meat has historically used the fat of the animal sealing out all contaminants like duck in confit generally stored in cellars. Bacon fat can be left out as well as butter, although butter not as long because of the milk solids, but you get the picture, right?
I'll go into more detail for the people that might be interested.
Think of a fat as a chain with links and each link represents a specific type of fatty acid with around 22 or more links and are attached or bonded to a hydrogen atom and are determined by the way these carbon atoms are bonded within the chain.
For example saturated fats are always single-bonded where a monounsaturated fat has one space, hense mono, which creates a kink in the chain and a polyunsaturated fat have 2 or more creating extra kinks, basically it's the loss of electrons that are missing that creates this situation. Because saturated fats have no kinks they lay tightly packed and why they're solid at room temp. The unsaturated fats, the mono and poly fats can't do that and why they are liquid at room temp. The kinks allow for what's called oxidation because these kinks (gaps, kinda) allow exposure to outside forces, them being oxygen, light and heat. We really don't want to be cooking with poly fats.
It's oxidation that forms lipid peroxides, free radicals, and other compounds like aldehydes that are toxic and cause cell damage and are associated with various health issues, including inflammation and vascular diseases. The other issue with consuming too much polyunsaturated fats is inflammation from the imbalance it creates with our omega 6 to our omega 3's.