Smoke Points of Various Fats

Thanks to Florian for providing the Celcius conversions!

Methinks that grapeseed oil when it can be purchased at a reasonable price can replace peanut and coconut oils for high heat uses. Your chart shows grapeseed with an adequately high smokepoint for a cooking oil. It is light and drains easily. Some say it actually lowers cholesterol -- opposite the popular deep frying oils.

Sorry to add this extra comment, but as I thought, most sites report grapeseed oil with a smoke free range from 420F to 485F -- plenty hot. It maintains its healthy properties at the highest cooking temperature (up to 485 degrees F).

No Cholesterol
No Sodium
No Trans-fatty acids
No preservatives
High in Antioxidants
Vitamin E: 11-22mg/serving
Highest concentration of monounsaturated and polyunsaturated fats of any oil
Lowest level of saturated fat of any oil
72+% Lineolic Acid (Omega 6)
May help increase HDL (good) and reduce LDL (bad) Cholesterol

There is a grapeseed oil fact sheet at http://www.deerfieldranch.com/FactSheets/GSO.Fact.sheet.html

I don;t sell it. I just have learned to use it a lot.

I welcome all comments.

A few comments on your assessment of grapeseed oil:
No Cholersterol, sodium, trans-fatty acids, preservatives - these are true for all pur vegetable oils.

High in antioxidants and vitamin E - yes, grapeseed oil is a good source for vitamin E.

Highest concentration of mono and poly of any oil - untrue. Canola and safflower are two commonly available oils with lower saturated fat. (And in my fats article I note that avoidance of saturated fats may not be a healthful choice. In fact, high consumption of polyunsaturates should be avoided.) Unlike canola oil, grapeseed oil is mostly polyunsaturated.

Almost all of the polyunsaturated fatty acids in grapeseed oil is linoleic acid which is an omega-6 fatty acid. High consumption of omega-6 oils is not recommended as it inhibits the body's ability to process alpha-linolenic acid (omega-3) fatty acids. Don't get me wrong, omega-6 is essential, but (at least in the U.S.) we get a large amount of omega-6 in our food already. Supplementing your diet with an 72% omega-6 oil may not be such a good idea.

I'm not familiar with the ability of grapeseed oil to increase HDL and reduce LDL counts. Anyway, I don't take too much stock in the cholesterol hypothesis.

Mary Enig suggests an equal parts combination of coconut oil, sesame oil, and olive oil for frying for maximum health benefits.

I use either extra light olive oil or canola oil for my frying currently as it is difficult for me to purchase other beneficial high heat oils at a price point that I am willing to spend.

I am impressed with the smoke point tables and realy the whole site.

I have recently become aware of an oil (widely available) from india called,
"Gingelly Oil" which has nice properties and is inexpensive hoowever takes some practice with getting used to mixing the taste into things. I'm looking for info on this oil if anyone has any???

Gingelly oil, according to my understanding is just sesame seed oil. It's just called by a different name in India.

Someone tell me if I understand this correctly, and comment on how this effects the "healthfulness" of otherwise healthy oils: polyunsaturates, while considered healthy, become trans-fatty at 360 F. If we agree-- and most seem to-- that trans-fat is far less healthy than even saturated fat, then this heat makes sesame, flax, et al less healthy than beef tallow. One is definitely inclined to use a low-poly oil for frying at high temperatures, but these usually don't have the highest smoke points. What then?

Can anyone shed any light on Tea Oil used for cooking? It is not very common but apparently from the reports I've read regarding its properties, it seems to be as healthy as olive oil, with an 82% mono fat content, and a low 10% sat fat content. It also boasts a high smoking point and decent levels of Omega-3's. So why is it so uncommon?

I was looking at the list for smoke points ofr certain fats, but i did not see duck fat. I was wandering if anyone knoew the smoke point ofr duck fat. I am a chef and I would like to use duck fat as a cooking medium in my deep fat fryer to cook with, especially our house made potato chips. If anyone knows the temperature I would greatly appreciate to get the information. You can contact me by email at ChefJRD@aol.com. Thank you

Very interesting info on cooking oil.
How about posting references on scientific information
in general, so it's not just like rumor which gets
so tiresome after seeing it much.
That was the nice thing about Laurel's Kitchen cookbook.

HI
My name is chris I am a chef in Cincinnati Ohio. I was wondering if there is a chart or formula for the point when the oil lights on fire or flash points. Chris

I found the following information at http://www.diabetesincontrol.com/modules.php?name=News&file=article&sid=2385


Duck and Goose Fat – this was used in traditional Jewish cooking, even more so that chicken fat. As with any animal, the omega-3 to omega-6 ratios varies depending on their diet.

· Omega-6 to omega-3 ratio – 13:1
· Omega-3 fatty acids = 0
· Omega-6 fatty acids = 13%
· Omega- 9 fatty acids = 52%
· Saturated Fat = 35%
· Smoke Point = 375 F

Michael, trans fats are made through the process of hydrogenation. While heating an oil past its smoke point will cause it to break down and oxidize, it DOES NOT cause trans fats. Definately *avoid* shortening and partially hydrogenated vegetable oils! It's a good idea not to cook any oil under high heat circumstances.

Would you please explain to me what it means for oils to be "refined," "semirefined," and "unrefined," or none of the above, and which of these correspond to the stuff you find on the shelf at Kroger and Safeway?

There are apparently huge differences in the characteristics of the oils, depending upon whether or not they are "refined." For example, your chart shows:

Unrefined safflower oil 225°F
Semirefined safflower oil 320°F
Refined Safflower oil 450°F
Safflower oil 510°F

That's an astonishing range of temperatures!

Thanks,

-Dave
dave263 at burtonsys.com

do you know what the smokng point for unrefined grapeseed oil and refined grapeseed oil?

I have grapeseed oil's smoke point listed at 420°F. Assume refined if I don't list another version. As to unrefined grapeseed oil, I wasn't able to find this info. Anyone know?

Hey i was wonderin for my school project, does oil have the ability to preserve food? :)

Yes, oil potentially has the ability to preserve food, but this must be carefully done. Oil is used in preservation by creating a (mostly) oxygen free environment if the object to be preserved is fully submerged in the oil. However, some bacteria and spores can survive (and even thrive) in an oxygen deficient environment. Only attempt to preserve food if you are experienced in this or are learning to do it from someone who is experienced.

I'm not sure why anyone would want to A) Deep fry at a temperature higher than 375 degrees, and B) Saute at a temperature higher than about 300 degrees. So, why would one need grapeseed oil for its high smoke point? (I use it because it has a clean, neutral flavor and a light viscosity.)

stirfrying, perhaps?

true, high high on unstable oils creates lipid peroxides, which are also unhealthy.

You stated
I disagree they are not impurities, they are associated cofactors/enzymes that I consider as nutrients.
We learned in chemistry that oils can quicky go rancid if left in the light (photoreactive) as well as oxidize. Isn't it interesting that most oils at the store are in clear bottles that have a shelf life of 2 to 3 years if not longer, whereas their counter parts unrefined oils will decompose and go bad within months.
Why is that I believe it is because of the refining process, oils put under high temperatures and all "impurities as you put it" have been removed. Thus increasing shelf life so the store owners don't have to throw it away.

This same mentality has been used with Milk and Eggs, does anyone remember how Milk used to only last a week before curdling. Now it lasts twice as long. Remember when we used to crack eggs and sometimes would find alittle white thing in there along with some blood, not anymore what happened how come? eggs used to go bad in our fridge within 2 weeks, that was fun because we used to get them to have an egg war. Unfortunately not anymore, Im older now but Ive had eggs in the fridge for 3 weeks and after opening them they looked fine why is that?

sorry for the long statement, main point is that oil reacts to light but not any of the oils at the store why?

smilesalot@mindspring.com

I live in the UK, so this may not apply to where you live... but....

Over here, milk lasts longer than it used to because of the advances in pasteurisation. This (as I understand it) is treating the milk to kill any bacteria in it that cause it to go bad. This lengthens shelf life by a huge amount, although once the milk is opened, it will go off eventually due to bacteria "migrating" into the bottle. If you want an even longer shelf life, then you can buy UHT (Ultra High Temperature) milk, which is essentially boiled at high temperatures to kill virtually all bacteria.

Eggs no longer have those spots in them because they are unfertilised. This means that there is no chance of getting chicken embryos in the eggs. Our eggs are also lion-marked, meaning that the chickens that leyed them were vaccinated against Salmonella.

It's interesting that you pointed out *exactly* what's so convenient and disturbing about current food processing. People want milk that looks the same throughout (i.e. not with cream on top and separation of fat particles) and that lasts longer than a few days. We also want eggs that don't look like little embryos. We especially don't want to risk getting sick from our food and so many of our foods today are irradiated, homogenised, pasteurised, sterilised and so on.

Brigning it back to oils, the question of why oils last so long on the shelf is a good one. And why doesn't canola oil smell like....anything? The refining process requires a lot of mechanical pressure and heat and the oils simply oxidise. Then they have to bleach and filter them to get them to look the way they do in those clear bottles on the shelf. If you can find Rapunzel oils in your local health food stores, you should splurge sometime on a bottle of their organic, unrefined canola oil. It's a rich yellow colour and has the most amazing smell and taste. I love to bake cookies with them (being sure to keep the oven below 300F) yum!

But of course, the smoke point is then so much lower with unrefined oils. I try to do the olive oil/coconut oil combo when I need to stir-fry, and then I drizzle on sesame oil at the end just for flavour.

A friend of mine and myself were having a fairly heated (haha geddit!) argument the other night (albeit after a few beers) over whether sunflower oil or olive oil burns at a higher temperature... I said sunflower oil burns hotter, and so is better for things like stir frys, sauteeing etc... I think this shows I was right, although we didnt specify the exact conditions... Going with the unrefined values... I win!

Thanks for settling this!!! :D

This is actually all wrong. I (well actually my wife) produce eggs for the local farmer's market. We don't do _anything_ to our chickens, just give them food and water and shelter, and steal their children.

The eggs we sell do occasionally have blood or meat spots. Commercial eggs don't have those because they are "candled". This originally meant that someone literally held each egg up to a candle, looking for any weird shadows that indicated something not quite right. Modern egg production uses machinery, including a contraption that rolls eggs past some sort of optical electrosensor. This is also the main reason that white eggs are so popular in the US: they're much easier to candle (which means the producer would rather deal with them) and the candling results are more certain (which means the consumer is happier with them).

We rarely get complaints about blood or meat spots, nor do we often find them in the eggs we eat. I believe this is because our chickens are healthy and active. Meat spots are literally bits of chicken meat -- bits of the hen that broke off and got incorporated into the egg while it was being produced. Imagine something similar to the colon polyps we're all told to watch out for. Blood spots are likewise bits of blood that leaked in during production. These things can happen as part of normal wear and tear in the bird. But imagine birds that live in 1x1 foot cages where they can barely turn around, fed high-energy feed full of hormones and god knows what else (probably not antibiotics -- I think that's actually illegal in the US, even for the big commercial operations). Birds that aren't healthy or physically fit. I imagine these birds probably make more blood & meat spots than ours. I have no specific facts to back this up, just the observation that we seem to have very few spots in our production. Not enough to warrant the effort of candling.

The only machine we use is a compressor to bubble air into an egg bath. We "wash" our eggs in dilute baking soda (sodium bicarbonate) solution.

Our eggs are fertilized (roosters run with the hens). We label them as such: "fertilized", not "fertile". We refrigerate our eggs (ok, I was wrong, that's a 2nd machine. The car we drive them to market in is as third.) Refrigerated eggs can sometimes be hatched, but they are not reliably fertile. If someone wants eggs for hatching, we make special arrangements to bring them un-refrigerated eggs. We are careful to label "fertilized" because this matters to certain subspecies of vegetarians.

Our eggs never look like embryos because bird eggs do not begin to develop until they have been held consistently warm for about 48 hours. This is a natural mechanism to prevent a nest full of eggs from hatching one by one (which results in mama hen wandering off to care for the first hatchling, and the rest of the eggs dying of cold). Mama bird lays an egg, sits on it for an hour or so, wanders off to eat, has a normal day. That night she sits on the eggs and keeps them warm all night. Repeat the next 6-10 days. Eventually there are enough eggs, she decides to seriously sit. That first egg has been sat on (brought up to body temperature) many times, possibly 10 times for 8-12 hours each time, but it has not progressed any farther in development than the last one laid. All the eggs in this nest will develop at the same rate and hatch within 12-24 hours of each other (21 days later, for chicken eggs).

Eggs do not go bad in 14 days in the fridge. Eggs don't go bad in 14 days on the counter, even a sunny counter. Before we started selling at the market, we often ate our own eggs that had been refrigerated for five months. By then they were starting to get runny, but still perfectly edible. If your mom gave you the eggs after 14 days, it was because she believed they were too old, not because they were actually going bad.

The USDA currently requires eggs to be labeled with their pack date and an expiration date 30 days later. Note that it is the pack date (which could be arbitrarily later), not their lay date. We label with the lay date, which is technically in violation, but always earlier or the same as the pack date (so at worst we are making our eggs "seem" older than they are, by their standards).

It may be that the USDA (equivalent agency back then?) used to require a 14-day expiration stamp. So your mom believed it and gave you eggs to throw. Now you're in charge of the fridge and you believe the 30 days stamped by today's standards.

Note that you cannot reliably expect store-bought eggs to last for 5 months in the fridge. Because the USDA has producers label by pack date, you really have no idea how old your eggs are. There's actually a reason that producers might deliberately age eggs: truly fresh eggs don't hard boil well. Well, they boil just fine, but they're really hard to peel. Bits of egg white stick firmly to the shell; you end up shredding the white pretty badly. If one brand of eggs had that property and the next one didn't, which one would still be on the market 6 months later? So there's a strong incentive for egg producers to age their eggs a few weeks, despite the inventory management costs. Once you have the necessary warehouse space to handle this rotating inventory stream, the exact age of eggs making it to store shelves is going to ebb and flow according to how the chickens are producing and how many eggs people are buying.

We don't do anything specific to combat this. If a customer mentions they intend to hard-boil, we steer them to an older dozen (we go to market every 1-2 weeks, so we have eggs at least a week old). We tell them to save the eggs a couple weeks before using them for that purpose. And we tell about a couple tricks: lightly crack the egg before boiling (it will leak a bit but may be easier to peel); themally shock them after boiling (drop into cold water until cool, drop back into the still-hot boiling pan). We haven't actually experimented enough with these techniques ourselves, we just use old eggs for hard boiling.

Signed,

Part-time chicken engineer.

Oh yes it does! :P

Here's the chemistry. "trans" and "cis" refer to the shape of otherwise identical molecules. In an unsaturated fat, there are occasional double bonds. This leaves two adjacent carbon atoms with only a single hydrogen attached to each instead of the usual two. This produces a slight push on one side of the chain. Hence the molecule can take either of two shapes: if the hydrogens are on the same side, the chain gets a (double) kink, if they are opposite, there is just a tiny zig-zag and the chain remains pretty well straight.

So we have:

[code:1:a14ae8a3ca]

H H H H H H
| | | | | |
-C-C-C -C-C-C H H
| | \\ | | \\ | |
H H C-H H H C-C-C-
| | | |
H-C-H H H H
|
H-C-H
|

cis trans

[/code:1:a14ae8a3ca]

The natural form of most fats is the kinked "cis" isomer, the straighter "trans" form is unnatural and harmful. Both forms are stable at room temperature. However, when oil is heated the thermal vibration can wrench the double bond around into the other position. This occurs below the smoke point, so high temperature cooking transforms some of the natural cis fat into the harmful trans variety. It is not entirely negligible - this is one of the reasons they recommend not using cooking oil over and over again.

Regards, Derek Potter

One more off-subject comments on the eggs -- I also have had chickens and raised my own eggs, and one of the first things I noticed was how much thicker the shells were on my home grown eggs.

Here is my hypothesis -- grocery store eggs come from chickens fed the bare minimum to get the product to market and maximize profitability. Thin shells are the result of less availability of minerals in the chicken's system to produce a thicker shell. Thin shells also allow the eggs to be "candled" or optically inspected more efficiently (for all of us consumers that value predictability in our egg cracking experience). Thin shells also allow oxidation of the eggs (the process that causes spoilage as evidenced by that little bubble of air you find between the membrane and the shell in older eggs, and allows you to do the "float test" to determine an egg's freshness before you are unpleasantly surprised). So, grocery store eggs spoil faster IMHO, and are less nutritious (because that same programming principle of garbage in -- garbage out also works for food processing)

Am I far off the mark, anyone with more knowledge and less experience in this area?

mualpha@alltel.net

Is it more harmful to deep fry something or styr fry something lets say chicken for instance and about how much harmful is one over the other.

Improvement of cholesterol levels is attributed to all unsaturated fats : http://www.hsph.harvard.edu/nutritionsource/fats.html

i did not realize that soybean, safflower and avocado oils have very high smoke points. the oil that is not on the list but is getting a lot of attention is rice bran oil - smoke point 490 f /254 c. i use it to coat barbecue grills before grilling and it does a great job in preventing the meat from sticking to the grill :)

However, another source for similar information (admittedly less objective by nature) is Spectrum Organic's 1-2-3 guide to cooking oils. They offer a bunch of different oils at reasonable prices and their guide is written for their oils, so at least you know what product they refer to. (NOW oils seems to process their products in a similar fashion, FWIW).

It is a PDF file, but otherwise it is about perfect.

http://www.spectrumorganics.com/index.php?id=182&findall=smoke+point

Sorry, failed to preview the link before posting...

Use this direct link to the PDF file of the 1-2-3 cooking guide to avoid having to click through.

It does not cover rice bran oil, of which I bought a 16oz. bottle for $5 and used for a bo luc lac yesterday evening. It worked well at high heat, so there are some oils worth exploring which are not in the 1-2-3 guide. But the guide is more specific and less confusing than Mr. Chu's (great!) table, above.

Hope this helps others to choose wisely.

B) How about rice bran oil-HOT-HOT-smoke point 490 degrees and of course you want to fry at a high heat- why not with a good trans fat free cooking oil.

You can always find rice oil at www.californiariceoil.com. It is a good value.

Lots of people keen on their cooking. I have taken to using beef dripping or lard as approriate when cooking meats, a much more suitable flavour, of course.

What brought me to the site however is my seach for a heat transfer oil, anybody know some flash and fire points of high temperature oils. also why do manufactures bother to make synthetic ois for heat transfer when these veg oils have such higher smoke/flash points?

John.

Does anyone have any recommendations for an oil to use in seasoning cast iron cookware? Most of what I have always been told to use was either vegetable shortening or liquefied bacon fat. I'm about to re-season mine and wonder if a something with a higher smoke point would last any longer or if any are more resistant to acid attack (such as tomato based sauces).

I like to cook with Grapeseed oil. It has a high smoke point-around 420F and has VERY little taste. To season cast iron with it, you need to coat the pan well and "cook" the pan above its smoke point so the oil carbonizes. I'd bake it at 450F in an oven for an hour. When you take the pan out, let it cool and it must be smooth and NOT tacky to the touch. If the pan is sticky, all you have is a dirty pan. Put it back and cook it longer or if your oven never got to 450, check the temperature with an oven thermometer and cook it again.

Also, take a look at this thread. Jorg's technique works.

http://www.cookingforengineers.com/forums/viewtopic.php?t=372&highlight=seasoning+cast+iron

Well I tried the grapeseed oil technique.

I poured some grapeseed oil inside the pan, then used a paper towel to spread it around the rest of the pan (bottom, handle, and sides), baked at 400 F for 45 minutes, spread another layer on and baked at 450 for 45 minutes and 500 for 45 minutes (since I've seen the smokepoint of the oil varied here between 420-485 F).

What turned out was mostly perfect. The inside of the pan was as smooth as could be (not gummy anywhere) but also appeared somewhat striated. To explain, it looked as if some of it had carbonized at different rates in little pools or bubbles, but being that I put it on the rack upside down, this could not be the case. The rims of the pan, on the other hand, appeared almost powder coated in some spots and had raised areas of carbonization. These were easily scraped off with a thumbnail and revealed what looks like *rust* on the underside of these raised areas. This, too, came off with a fingernail, but it certainly looks a lot like rust.

I have decided that I will put more oil on the inside and the rim and try this again at no more than 450 F.

When reading Michael's comments on Polyunsaturated fat, I am unsure of how he comes to the conclusion they are bad and should be avoided. I am studying nutrition and I have learned they are good fats- in fact, the best fats. He is right in saying too much Omega-6 fatty acids are bad, and we do get enough or too much in our diets, but it is the ratio of Omega-3 to Omega-6 fatty acids that is important. Omega-3's are polyunsaturated and are the most beneficial to your health when you are getting Omega-6's. Michael says a diet high in polyunsaturates should be resricted, and I don't know how he can come to that conclusion. When he says, "And in my fats article I note that avoidance of saturated fats may not be a healthful choice. In fact, high consumption of polyunsaturates should be avoided" he is giving people false information. Saturated fats are much worse for blood cholesterol levels and overall heart health, and I don't think these claims that 'polyunsaturated are bad' is accurate. This is misleading people, and they need to know the full story- they need a ratio between 2:1 and 4:1 (Omega-6 to Omega-3) for optimal health benefits.
As well, do people really heat an oil past 100 degrees celsius? Most oils high in polyunsaturated fat won't be forming trans fats because most people don't heat their oil to a very high temperature. If they are using it for deep frying, they can use a high stability variety. This is by far the better alternative to saturated fats.

There is merit to what you say, but over the last couple years I've been reading more and more about the research conducted in this area and am leaning towards agreeing with Michael and his views on fats. It is true that a healthy ratio of n-6 and n-3 fatty acids should be maintained, but in the Western world we consume so much more n-6 than n-3 it's obscene (ratios of 6:1 or 10:1 are not uncommon). He doesn't say (I wouldn't back him up on this if he did) to cut out poly, just to limit consumption. This is because poly has a tendency to break down easily (not just through overheating, repeated use, but also in the stomach during digestion) and release free radicals. It's not an issue of poly turning into trans, but an issue of cancer causing agents being released into the body. Once way to combat this is to add an oil stabilizer such as acetic acid to your oil, another is to eat a lot of antioxidants. (Or, as Michael suggests, simply focus more on monounsaturated and saturated fats which do not have this problem.) Avoiding trans should drastically reduce your chances of heart disease; reducing consumption of poly should reduce your chances of certian types of cancer.

Also, on a different subject, Michael may be right about saturated fats. Experiments have to be performed again on saturated fats (not a mixutre of trans and sat fats as was previously done) to demonstrate if they are harmful to the body. The whole cholesterol consumption thing is bullshit as well (apologies for the language Michael)

Do you cook anything with oil? The pan barely sizzles with water when you heat oil to 100...

I'm not disputing the fact that too much Omega-6 is bad, and we already get too much in our diets. I completely agree with that.
The major issue I have is over the saturated fat. Saturated fat DOES raise cholesterol levels and clog arteries - unless I'm wasting my tuition studying nutrition. The american heart association has a section on trans fats you may want to look over.
http://www.americanheart.org/presenter.jhtml?identifier=3045790

Here is a study by professionals:
"Influence of n-6 versus n-3 polyunsaturated fatty acids in diets low in saturated fatty acids on plasma lipoproteins and hemostatic factors"
Author(s): Sanders TAB, Oakley FR, Miller GJ, Mitropoulos KA, Crook D, Oliver MF
Source: ARTERIOSCLEROSIS THROMBOSIS AND VASCULAR BIOLOGY 17 (12): 3449-3460 DEC 1997

In which they conclude "This study shows that in a group of healthy young men with an average plasma cholesterol concentration of 4.2 mmol/l (163 mg/dl) when consuming a diet in which fat supplies only about 30% of energy requirements, removal of saturated fatty acid leads to a reduction in their plasma cholesterol concentration."

This article, in my opinion, is unbiased and talks about some of the concerns you presented on omega-3's, however, it also seems to me that it supports Omega-3's as a better choice. There are so many factors you have to look at before you can make claims, I just don't agree with presenting people with misleading ideas that only present one side of the story.

But, hey, I guess a degree in computer engineering gives you the authority to influence what people eat.

If there is a peer-reviewed, scientific article published by a professional that says saturated fat is good and should be consumed instead of polyunsaturated fat, then I will take it all back.

And by the way:

Q. I was told that canola oil changed to trans fatty acids when it is heated, as in cooking. Is this true?

The phenomenon that occurs is vegetable oils is known as lipid oxidation or rancidity. Lipid oxidation involves the breakdown of fatty acids in the oil to produce secondary compounds that reduce the nutritive value and produce off-flavors and odors. Only under the most severe frying circumstances will the fatty acid composition of an oil be significantly altered. It is very rare for either the consumer or food processor to fry with an oil under the conditions necessary for the formation of trans fatty acids. The production of trans fatty acids to any significant degree in an oil without the use of hydrogenation is extremely rare. It is important to note that foods prepared in rancid fats are likely to be inedible due to the development of off-flavor and odors as well as deterioration in the appearance of the oil. The oil would likely be discarded before it could be subjected to the levels of light, heat and oxygen necessary to produce trans fatty acids

Source:
Canola Oil: Effects of Processing & Frying on Fatty Acid Composition, Canola Information Service.

http://www.westonaprice.org/knowyourfats/index.html

read "The oiling of america" as well as the other articles here on fats.

I am trying to choose a good healthy frying oil and dont care much for any of the olive oils, what are some of the pros and cons to sunflower oil?

What about cooking in a Wok? Proper technique with wok cooking usually involves very, very high temperatures -- using amazingly high heat output burners (I've read pro wok burners are up to 100k BTUs). Yet the Chinese use oil, how does this work? How do they not consume trans-fats, and damage the oil past the smoke point?[/quote]

I can't even imagine using a burner putting out 100K btu's of energy under a wok. I have burners running off high pressure gas valves that will put out 60K and 170K btu's, and I would never use even the 60K burner on full output for a wok. I use those biggies for boiling 40-80 quart pots with water for seafood fests and cooking massive amounts of corn on the cob at BBQ's for 100 people, and I still don't use them at full blast. For deep frying turkeys I use either of the big burners, but still never on high, even to get the oil up to my starting temperature.

A 100K burner used full tilt with a wok would simply turn the wok red hot and the food would just burn after a very short period of time--and I don't mean cooking time, it would just burn on the outside and the inside would just be raw. 30K btu for a wok is way more than enough, and once up to temperature, even that can be lowered. Basically, a good stove with 15-20K btu gas burners will do a fine job with a 14-16" wok.

Yes, Chinese wok cooking involves heating the oil way past its smoke or even (I've seen this in "open kitchen" Chinese restuarants) its flash point.
This may be a factor in China having the highest rate of stomach cancer of any country in the world.

Michael....you said..." The refined nature of extra light olive oil mainly affects taste and smoke point, but does not reduce the nutritional benefits of olive oil." :unsure:

this is completely contrary to anything i have read. CAn you please provide a source? It is my understanding that only Extra Virgin Olive oil is healthy. All 'light' and 'pure' olive oils, in my understanding, have been extracted with high heats or solvents.

Nutritionally, light olive oil and extra virgin olive oil are practically the same in terms of percentages of fatty acids. I haven't actually read a study that shows light olive oil is not as "healthy" as extra virgin - in fact, I haven't been able to find a real study showing why EVOO is considered to be a healthful oil. Most of that seems to be based around the anecdotal evidence that Mediterranean cultures consume a lot of EVOO and they appear to be healthy. There are some studies centered around the fatty acids proportions in EVOO, but if that's the case, then light olive oil is the same nutritionally. Healthfulness of a food is harder to define (especially when the other food - EVOO - isn't clear why it's healthful).

Wow! Thank you so much for the information and the chart!
I love your blog and hope you'll keep blogging for a long time.