You alway find out something new when you do actual research. I always thought bacon grease, butter, and coconut oil were ideal for frying. The reason? Well, don't they all have rather high smoke points? And isn't that because they are predominantly composed of stable SAFA?
Actually, SAFA is not the only fat in these supposedly safe oils for frying. For example, butter and bacon grease have MUFA ranging from 30-44%. Only coconut oil is overwhelmingly SAFA at 92%.
Now, let's take olive oil. It is majority MUFA (77%), and has PUFA (9%) comparable to bacon grease (8%) and lard (12%). Wasn't the reason for olive oil not being ok for frying due to its non-SAFA content? And wasn't this specifically due to its PUFA content (if MUFA were a problem, we shouldn't be frying with butter either)? If so, perhaps we should not be frying with bacon grease nor lard either, as they're basically meat drip from pork? I've heard anecdotal accounts of bacon grease being very unstable and having a low smoke point.
Another surprise: olive oil's smoke point is 375F, higher than 350F for butter and coconut oil. How does the smoke point differential between olive oil and other fats show that olive oil isn't fit for frying?
Here're the data:
- Coconut Oil: 92% (Saturated Fat); 2% (PUFA); 6% (MUFA); smoke point (350F)
- Butter, Unsalted: 66% (Saturated Fat); 4% (PUFA); 30% (MUFA); smoke point (350F)
- Ghee / Clar Butter: 66% (Saturated Fat); 4% (PUFA); 30% (MUFA); smoke point (485F)
- Bacon Grease: 48% (Saturated Fat); 8% (PUFA); 44% (MUFA); smoke point (?)
- Lard: 41% (Saturated Fat); 12% (PUFA); 47% (MUFA); smoke point (370)
- Olive Oil: 14% (Saturated Fat); 9% (PUFA); 77% (MUFA); smoke point (375F)
- Fish Oil: 25% (Saturated Fat); 50% (PUFA); 25% (MUFA); smoke point (n/a)
Data source: [http://www.fitday.com/webfit/nutrition/All_Foods/Fats_Oils_Dressings/Bacon_grease_or_meat_drippings.html] [http://en.wikipedia.org/wiki/Smoke_point]
Shouldn't the decision whether to fry or not be based on the relative fat content of these oils?
Edit: Added data on Lard, Ghee / Clarified Butter, and Fish Oil. Some more surprises. Ghee is basically unchanged from butter -- the clarification process slightly diluted its protein and carb content (negligible) but increased the smoke point from 350F to 485F. The fat composition however did not change at all -- minimal PUFA but significant MUFA concentration.
Lard is only 41% SAFA, 47% MUFA and 12% PUFA. At 12%, lard's is higher in PUFA than olive oil. Which raises a question: is lard really safer than olive oil for frying?
So let's examine the seminal question here by appealing to science, instead of spewing some rote Paleo answer that animal fats are safe for frying no matter what. Why is lard any safer than olive oil? Lard is basically pig fat and has higher PUFA than olive oil and bacon grease. We know that PUFA is unstable because it promotes lipid peroxidation -- a process that degrades PUFA's C-C double bonds, resulting in rancidity; the same process doesn't seem to affect SAFA nor MUFA. You wouldn't think of frying anything in fish oil (50% PUFA), right? Then why fry with animal (pig) fats (bacon grease and lard) that have lower but still not-too-insignificant PUFA?
Guys, read the question. He isn't asking what you are using to fry your food in. This isn't about sharing your cooking preferences. This is about cold objective data that will contribute to understanding why there exists a contradiction in the preferring of one fat over another, while they exhibit a similar make up of unsaturated fats.
ALWAYS cook with saturated fats. Butter and coconut oil are the best cooking fats. Then look to beef tallow and then lard.
Never ever cook with olive oil.
Keep it this simple. It will do you good!
Since starting Paleo a year ago, I use butter, coconut oil, ghee, and tallow for 99% of cooking and all stovetop cooking. I bake at 350-400F using only ghee or coconut oil.
About 1-2 times a month I'll use cold pressed sesame seed oil. I now only use olive oil for cold foods like salad dressing - I NO longer cook with it.
I use macadamia nut oil for searing fish in Bengali (Indian) fish curries because anything else tastes bad (in my opinion) at high temperature.
Traditionally cold pressed mustard oil is used but since it is not easily available in the US and in the past was adulterated in India (some died), I prefer to use macadamia nut oil - which is quite neutral and has a high smoke point. I use it only about max once a week.
I use duck fat and goose fat in addition to beef tallow, bacon grease, butter, and coconut oil. Don't overlook the rendered fats from our feathered friends. For example, potatoes cooked in duck or goose fat are divine.
I consider butter a low-heat cooking fat as it browns and burns quickly otherwise. I do use it for eggs because they do best with low heat anyhow.
My high-heat fat is coconut oil; I used to use grape seed oil in the bad old days. I find my grass fed beef tallow gets pretty smoky even at medium heat.
It would be interesting to see what is in corn oil/vegetable oil/soy bean oil/safflower oil in terms of PUFA for comparison, since those are no-nos. I'm wondering if that would better ground this discussion? Maybe this level of PUFA isn't so big in comparison to some of these other fats. For instance, see this chart I found online: http://chartsbin.com/view/1961
You make a really great point. Looking at this list, it seems that (with the exception of fish oil) all of these fats have "small" amounts of PUFA in them...which is to be expected since PUFA is found naturally in the plants/animals they come from...so then is it really just about smoke point in choosing a fat to fry with? In that case, avacado oil might be a good bet. It has a high smoke point (though I think it has more PUFA than some of these other "good" fats). Other options that look good might be ghee and palm oil. But yah, it would be interesting to know what level of PUFA is just awful/what small/large amounts of PUFA can do to you.