Real Food Right Now and How to Cook It: Cooking Oils

Like salt and black pepper, you probably reach for cooking oil for just about every meal you make. But have you ever wondered about the history of your canola oil, or what makes fancy extra virgin olive oil so expensive? Or what the heck margarine really is? Read on for all of this and more. 

A Little Background

Most cooking oils are pressed or extracted from fruit, vegetable seeds or nuts. The ways in which various oils taste and perform in the kitchen have a great deal to do with the way they have been produced and refined (or not refined, as the case may be). Below are a couple of buzzwords you might notice on cooking oil labels that are helpful to know. If you're interested in more nitty-gritty details of oil extraction and refinement, check out this and this.

  • Chemically extracted : Most non-organic, commercial oils (think soybean, corn, canola oils) use chemical extraction to remove the oil from the seeds. Generally, the seeds are washed, heated, pressed, flaked and then flooded with hexane, a petroleum product that is frightfully efficient at extracting oil from seeds. Unfortunately, hexane is dangerous to those who work with it and is difficult to dispose of safely. (The jury is still out as to whether consuming hexane-extracted oils is safe, but I'm personally not willing to risk it.) It should be noted that the FDA does not require that hexane extraction be listed on food labels, but it is not allowed in certified organic products.
  • Expeller-pressed : The oil is extracted via pressure by using a screw-like press. Expeller pressing is much less efficient than chemical extraction - a significant portion of the oil is not removed - and thus expeller-pressed oils tend to be more expensive than chemically extracted oils.
  • Cold-pressed : Because pressing oil can cause the oil to heat up (due to pressure and friction), some oils are pressed in cold environments or by using a cooling apparatus. Cold pressing is supposed to preserve flavor and nutrients.
  • Refined : Some oils are further refined after the chemical extraction or pressing process. Refinement removes various compounds in the oil, including color and other particles, fatty acids and other substances considered "impurities." Refined oils are extremely neutral in taste, by design.
  • Hydrogenation: Very simply explained, oils are hydrogenated via a chemical process that adds hydrogen atoms to the oil. As this article explains, the more an oil is hydrogenated, the higher the saturated fat. Fully hydrogenated oil (like shortening and margarine) is solid at room temperature. Chemistry is magic!
  • Virgin/Extra-Virgin: These are terms used to describe the pressing and refining processes of the oil, as well as the chemical composition. Generally, "extra-virgin" oils are cold pressed mechanically (i.e., without the use of chemical extraction). These terms are most frequently associated with olive oils, which are defined by the International Olive Council. They are also more recently being used to describe coconut oil.
  • Smoke point: The temperature at which smoke appears when the oil is heated. In general, the more refined the oil, the higher the smoke point. High smoke point oils are useful in high-heat cooking.

In true RFRN tradition, I've included a bit of information about the history, cultivation, environmental impact, characteristics and what to do with each of the oils below. I've stuck with the major found here in the United States.


A Brief History

Canola is a Canadian-developed-and-marketed oil pressed from the seed of a type of rape (Brassica napusor Brassica rapa), a member of the mustard family. The word "canola" is a portmanteau of "Canada" and "ola," which the Canola Council of Canada says means "oil" (in which language - I'm not sure). Canola was first developed in the 1970s as a response to the need for an oilseed crop that would perform well in Canada's prairies. Rapeseed oil, canola's forbearer, was used as a lubricant for steam engines and as a cooking oil (it still is, in some places), but developed a reputation as being "anti-nutritional" because several of its chemical components (namely erucic acid and glucosindes) have negative affects on the body. Canadian breeders developed "low erucic acid rapeseed" (LEAR) and re-branded the result as canola oil, thus eliminating the negative associations with rapeseed. Today, the oil must be less than 2 percent erucic acid to be marketed as "canola."

Cultivation and Environmental Impact

Canola is cultivated on a large scale in Canada and parts of the US. In North America, canola is usually planted in the spring. As might be expected, Canada leads the world in canola cultivation, followed by China, India and Germany. The canola industry is growing in the US; North Dakota produces the bulk of the American crop. According to the Canola Oil Council of Canada, 99 percent of canola planting in Canada is Monsanto-created seed, genetically engineered to be resistant to Round-Up (aka, glyphosate). (We've talked about GE seed and Round-Up before here, and you can read up on the ins-and-outs of genetic engineering here.) As you might expect, there has been a great deal of controversy surrounding GE canola in the US. First, the plant seems to have "escaped" its bounds - it's been found by scientists growing in the wild in North Dakota. There is also legal controversy: Monsanto sued a Canadian farmer, Percy Schmeiser, for patent infringement after Schmeiser saved seed from Round-Up ready canola that grew in his field. Schmeiser lost in Canadian court, but his battle with Monsanto highlighted issues with the escape of GE crops and the rights of companies like Monsanto to patent seeds. If you love canola but are concerned about these issues, organic canola oil is readily available. (Genetically engineered ingredients are not allowed in USDA-certified organic products.)

Characteristics, What to Do with It and Nutrition

Most canola oil is refined, meaning that it has a high smoke point, and is useful for frying, sautéing and stir-frying. It is also widely used in baking, as a component of salad dressings and to make margarine. It is a light, neutral-tasting oil, meaning that it doesn't add additional flavor to your dish or baked good. Canola oil is low in saturated fat - the least saturated of all cooking oils, according to the US Canola Association - and high in omega-3 fatty acids and monounsaturated fat - the good kind of fat. It's also a good source of vitamins E and K.


A Brief History

Coconut oil, unsurprisingly, comes from fruit of the coconut palm, a tropical plant that food historian Alan Davidson calls "the most useful tree in the world." There is some debate in botanic circles about where the coconut palm originated - with some arguing and Indo-Pacific origin, and others a tropical American origin. Either way, the coconut palm now grows across the globe in tropical climates.

Cultivation and Environmental Impact

Coconuts are grown on plantations across the tropics, but Indonesia, the Philippines, India, Brazil and Sri Lanka are the top global producers. As Maddie Oatman in Mother Jones pointed out, coconut farmers are frequently paid very little and exposed to dangerous pesticides. (Coconuts can also be dangerous to harvest.) A Stanford study done in 2010 found that coconut palms decrease soil nutrients, which may alter the feeding habits of animals and birds.

Characteristics, What to Do with It and Nutrition

Virgin (or extra virgin) coconut oil can be extracted from fresh coconuts, called "wet milling," or expeller pressed from dried coconut meat. Most commercial coconut oil, which is frequently referred to as RBD (refined, bleached, deodorized) coconut oil, is made from copra, the dried meat of the coconut. Virgin coconut oil is 92 percent saturated fat and is solid at room temperature, and white in color. Depending on how it is processed, it can have a mild to strong coconut flavor. Refined coconut oil is odorless and has a much higher smoke point than virgin oil. Here is a nice guide to selecting a good coconut oil. Virgin coconut oil has, of late, become the darling of the natural food world, purported to help with weight loss, oral health and even Alzheimer's disease.


A Brief History

Margarine (aka, oleomargarine or oleo, as my grandma used to call it), a solid or semi-solid substitute for butter, was invented in 1869 in France. According to the Oxford Companion to Food, Napoleon III, concerned about the scarcity and expense of butter prior to the Franco-Prussian war, devised a contest to invent a substitute. The winner, a man named Hippolyte Mège Mouriès, combined beef fat oil (called oleo), milk and water, and worked the mixture until it formed a white mass with the approximate consistency of butter. This he named "margarine." In the US and elsewhere, margarine was seen as a threat to the dairy industry because it was significantly cheaper than butter. Dairy farmers even lobbied to ensure that artificial colors, which would make the white mixture more butter-like, were not allowed. Margarine makers originally circumvented this rule by selling packs of yellow dye along with their margarine, to be mixed together to form a butter-like spread. Most states had repealed margarine restrictions by World War II. "Shortening" is a term used for any oil or fat that makes a baked product "short," or tender. Butter, lard, margarine and even oils can be considered shortening. However, in the US, vegetable shortening usually refers to a product like Crisco - a solid mass of hydrogenated vegetable oil, white in color and used in baking and frying. Crisco was invented by Proctor and Gamble in 1911 as a substitute for butter and lard.

Production and Environmental Impact

Both margarine and vegetable shortening can be made from any number of vegetable oils. Margarine in the US is most commonly made with soybean and cottonseed oils, while shortening is commonly made with palm, soybean and cottonseed oils. Production of both is a highly industrial process involving oil refinement, which includes degumming, flavor neutralization, bleaching and washing; the product then undergoes hydrogenation to make it saturated (and thus to harden it so that it does not melt at room temperature). In the case of margarine, water or skim milk is also added, along with colorings, flavoring agents and vitamins.

Characteristics, What to Do with It and Nutrition

If you're down with it, margarine can be used as a substitute for butter in most dishes and in some baked goods. Vegetable shortening is classically used in pie dough and for deep-frying. After a byproduct of hydrogenation, trans fats, were shown to increase "bad" cholesterol, many margarine and shortening manufacturers devised ways to advertise their products as "trans fat free" by switching oil types used in the manufacturing process.


A Brief History

Olives have a rich and interesting history, which we discussed in our recent RFRN post on the fruit. Native to the Western Asia, where there is archeological evidence that the fruit was gathered from wild trees as many as 10,000 years ago, olives were first cultivated in the Middle East. From there, they spread across the Mediterranean. According to food historian Alan Davidson, stone crushing olive mills and presses and oil storage jars have been found all over the Mediterranean by archeologists - the ancient Romans perfected olive oil extraction technology as far back as 2,200 years ago.

Cultivation and Environmental Impact

Olives (Olea europaea)grow on beautiful little trees with silvery green leaves. Olives must be harvested ripe and undamaged, and crushed without breaking the hard stones inside the fruit, to produce superior olive oil. As you might guess, Spain, Italy, Greece, Turkey and Morocco lead the way in global olive production; in the US, California produces the bulk of the olive crop. There is also a burgeoning olive industry in Georgia, where chefs like Sean Brock are championing Georgia olive oils in their local cuisines. Katie Sweetman discussed the environmental impacts of olive production here, but the bottom line is that water management and runoff is a problem in some olive-producing countries.

Characteristics, What to Do with It and Nutrition

As we discussed above, the International Olive Council classifies olive oils based on method of processing and chemical composition; here is their guide to the various types of olive oils. The most highly prized olive oil is designated "extra virgin," and is extracted mechanically. It is fruity and peppery, with a low smoke point, and can range in color from yellow to green. The jury is out as to whether you should fry with extra virgin olive oil (or do anything aside from drizzle it raw onto salads and the like), but I follow my Italian food idol Marcella Hazan and use extra virgin olive oil just about everywhere - I love the rich flavor it imparts to savory dishes of all types. Oils marked simply "olive oil" are a blend of extra virgin and refined olive oils. Refined olive oil is made much like other refined oils - it's fairly neutral in taste and has a much higher smoke point than extra virgin olive oils. Here's a nice roundup of olive oil recipes.

Recently, the olive oil industry has come under fire for high-profile arrests of oil dealers adulterating their oil with inferior oils, like safflower. Here's a great guide to avoid being duped. (And apparently it is soon going to be even harder to find real olive oil - Tom Philpott over at Mother Jones has the scoop on this impending "Olive Oil Apocalypse.") Olive oil is low in saturated fat, and high in vitamins E and K. The oil is high in monounsaturated fatty acids, which have been linked to heart health and lowered cholesterol levels.


A Brief History

Native to the West African coast, the oil palm, from which palm oil and palm kernel oil are made, is now grown in tropical areas across the globe, originally spread to far-flung locales by Portuguese traders in the fifteenth century. In Africa, palm oil was (and still is) made the traditional way by pounding and boiling the fruit, then skimming off the resulting oil. The Oxford Companion to Food explains that in the later part of the 19th century, Europeans began to extract palm oil themselves (rather than buying the extracted oil from Africans), and around the same time the first oil palm was brought to Indonesia, where production of the oil took off dramatically. By the 20th century, palm oil was in high demand as the margarine industry ramped up. Palm oil is has since become persona non grata in the cooking oil world, as it has been justifiably linked to rainforest deforestation and resultant habitat destruction. Palm oil is now the most used vegetable oil in the world.

Cultivation and Environmental Impact

African oil palms (Elaeis guineensis) are beautiful trees on which grow large clusters of reddish-orange fruit. Palm fruit oil is extracted from the pulp of these fruits, while palm kernel oil is made from the inner, harder kernel. Indonesia, Malaysia, Nigeria, Thailand and Cambodia account for most of the world's production of palm oil. Unfortunately, oil palm plantations are wreaking serious environmental havoc in these places. The situation is quite dire in Indonesia and Malaysia, where tropical forests, home to orangutans and Sumatran tigers (along with many other less sexy, but nevertheless important species), are being degraded at a truly heartbreaking rate - even outstripping deforestation rates in the Brazilian rainforest. (And two species of orangutans in Borneo are listed as endangered or critically endangered.) Not only does rainforest destruction cause habitat loss, but slash-and-burn clearing also releases greenhouse gasses, which contributes to climate change. Check out this interactive guide to the issues with palm oil from The Guardian.

Characteristics, What to Do with It and Nutrition

Palm oil and palm kernel oil are ubiquitous in processed foods, especially commercial baked goods and snacks. (Yes, even in Girl Scout Cookies, despite a by Girl Scouts to stop.) Unlike most other vegetable oils, they are both highly saturated and solid or semi-solid at room temperature. Unrefined palm oil is generally reddish or dark orange, and can have a mild carrot-y flavor from the carotenes that cause its coloration. Organic, sustainably grown red palm oil is available. If you can find sustainably produced red palm oil, here are a few recipes to try out its distinct flavor. More common is refined palm oil, which is much more neutral-tasting after refinement (which includes bleaching, degumming and deodorizing) and has a higher smoke point. Unrefined palm oil contains a great deal of vitamins A and E. Palm oil is a common cooking oil in the cuisines of Brazil, Southeast Asia and West Africa. Palm kernel oil is even more saturated than palm oil; it, too, is used extensively in commercial cooking and processed foods.


A Brief History

We discussed the fascinating history of goober peas (aka, peanuts) in our RFRN installment on the legumes. The upshot is this: peanuts hail from South America, where they were "discovered" by the Spanish and the Portuguese, and subsequently introduced all over the world. They flourished (and still do) in the US South, parts of Africa and all over Asia. According to the weirdly fascinating book Vegetable Oils in Food Technology , the French and the British began importing peanuts for oil pressing in the middle of the 19th century. Globally, over 50 percent of the world's peanuts are crushed for oil processing.

Cultivation and Environmental Impact

Peanuts grow just like other legumes, with one critical difference: after their blossoms drop off, the stalks elongate and push themselves underground, where the peanuts form. The plants require a long, warm growing season and lots and lots of water. As we mentioned in our peanut post, in the US they are infrequently grown organically and are frequently intercropped with cotton, 96 percent of which is genetically engineered to be herbicide tolerant. (Which means lots and lots of herbicides on the crop.)

Characteristics, What to Do with It and Nutrition

Organic unrefined peanut oil is available, and is quite delightful. Far more common is refined peanut oil, which is a neutral-tasting oil and has a very high smoke point. It is commonly used for deep and stir-frying and in salad dressings. Peanut is a popular oil in Chinese, Southeast Asian and South Asian cuisines. It is high in vitamin E and omega-6 fatty acids.


A Brief History

We talked about soybean history in our edamame post from last year - but here's the skinny: soybeans are native to China, where they have been used for millennia. According to the Soy Info Center, the first appearance of the Chinese term for soybean oil appeared in the 11th century.

Cultivation and Environmental Impact

Soybeans (Glycine max) are legumes that grow much like other bush beans. There are different soy varieties used for oil, for edamame and for other soybean products, like tofu. For oil production, the bean is allowed to mature on the plant, after which it is harvested and prepared for processing into oil. The Soy Info Center says that over 90 percent of the world's soybean oil is processed via chemical extraction, using hexane. The US, Brazil, Argentina and China are the top producers of soybeans, and soy represents 65 percent of the oil market here in the US. As of 2012, over 90 percent of US-grown soy was genetically engineered (GE) to be herbicide resistant, which translates to lots of herbicides used on US soy crops. Globally, the demand for soybean oil and other soy products is affecting the rainforest in South America, as large tracts of land are clear cut to make way for soy plantations. Read more about soy's environmental impact here and here.

Characteristics, What to Do with It and Nutrition

Soybean oil is neutral tasting, highly refined and has a high smoke point, making it useful for deep and stir-frying and for baking. It is also used in commercial processed food. Many oils marketed as "vegetable oil" are, in fact, soybean oil (but sometimes also safflower oil). Soybean oil is very high in Vitamin K, has some Vitamin E and is rich in omega-6 fatty acids, and to a lesser extent, omega-3 fatty acids.


Cooking oil can be made from many different nuts and seeds. Some other oils of importance in the US and globally include:

  • Corn oil is extracted from the germ of field corn kernels. It was first produced in 1889. (We went over the history of corn in our RFRN post on corn if you want to learn more.) Most corn oil is chemically extracted and highly refined. Refined corn oil has a high smoke point.
  • Cottonseed oil, pressed from - you guessed it - the seeds of the cotton plant, and usually highly refined. It is frequently turned into margarine and shortening, and used in processed foods and for frying. China, India and the US are the top producers of the oil.
  • Grapeseed oil, a byproduct of the wine industry, has a neutral taste and high smoke point, and is useful as an alternative to canola for frying and baking and in salad dressings.
  • Safflower seed oil, which is made from the seeds of a lovely yellow flower related to the sunflower (and used since antiquity for a natural yellow dye). Safflower seed oil is neutral tasting, usually highly refined, and can be used for deep-frying and in baking. Mexico, Kazakhstan and India are the top global producers of safflower seeds.
  • Sunflower seed oil, pressed from the seeds of a type of sunflower, is also usually highly refined and used in processed foods and baked goods. Like safflower seed oil, refined sunflower seed oil has a high smoke point, is neutral tasting and can be used for deep-frying and for baking.
  • Sesame oil is an important cooking oil in Chinese, Japanese, Korean and Indian cuisines. It is less commonly refined than the other cooking oils on this list, and has a nice nutty flavor. Toasted sesame oil, made from the toasted seeds, has a very strong sesame flavor and is most commonly used as an oil for drizzling and in sauces.
  • Other nut and seed oils include argan, walnut, almond, pistachio, pumpkin and avocado oils. These are usually unrefined, quite pricy and used for drizzling and dipping.


High-quality cooking oils should come in a dark glass bottle, as light increases the possibility of rancidity. However, the more refined the oil, the less likely it is to go rancid. Keep cooking oils in a dark, cool place to prolong their life. I keep my fancy nut and seed oils (like walnut, toasted sesame and pumpkin seed) in the fridge to prolong their life even further, especially since I don't reach for them as often I do olive, grapeseed or organic canola.

This post was originally published in December 2014.

Responses to "Real Food Right Now and How to Cook It: Cooking Oils"
The views and opinions expressed by contributors do not necessarily reflect those of the Ecocentric Blog or GRACE Communications Foundation.

  1. sue wiley

    thanks for indepth info re oils.

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