Nowadays there’s a plethora of options when it comes to selecting fats and oils for cooking. And with each offering having its own nutritional content, it’s not just a matter of choosing oils that are healthy but also oils that remain healthy after cooking with them.
Oil Oxidation
When choosing cooking oils, especially when you intend to cook in high heat – it is best to use oils that are stable and don’t oxidize easily. Oil oxidation is an undesirable chemical reaction that degrades the quality of an oil eventually producing rancidity thus causing changes in its flavor and smell.
Th oxidation effect of heating oils to their smoke point doesn’t stop with the release of harmful chemicals. It continues as the fatty acids in the oil also become oxidized forming even more free radicals which raises our risk for heart attack, stroke, cancer and other problems.
Made of carbon and hydrogen atoms, the fatty acids in oil are the building blocks for the fat within our bodies and the food we eat. When we digest food, the body breaks down fats into fatty acids which can then be absorbed into the bloodstream to support many important functions in the body among them energy storage.
Fatty acids are divided into 3 types: saturated, monounsaturated, and polyunsaturated. Each type of fatty acid having a single or a double bond of carbon to hydrogen atoms. It is the way these bonds are created that determine how chemically reactive and sensitive to heat the oil is. Therefore, one of the most important criteria to consider when choosing an oil is to know its oxidation point both at high and low heat.
For instance, in a saturated fatty acid, one (1) carbon atom bonds with two (2) hydrogen atoms (1C→2H). In other words, the carbon is “saturated” with hydrogen. This saturation makes the fatty acid very stable and as such can withstand high heat temperatures before becoming rancid.
On the other hand, the bond of a monounsaturated fatty acid has two (2) carbon atoms bonding with one (1) hydrogen atom (2C→1H). So the carbon is said to be “unsaturated.” Therefore, oils containing monounsaturated fatty acids are less stable than oils containing saturated fatty acids.
Lastly, polyunsaturated fatty acids have two (2) or more carbon pairs bonding to a hydrogen atom (2C2C→1H) which makes this type of fatty acid quite unstable at high temperatures.
In summary, saturated and monounsaturated fats are both better alternatives to use when cooking at high temperatures. Conversely, oils that are high in polyunsaturated fats are the least recommended for cooking.
The rest of this article, we will dedicate to discussing different types of oil based on their oxidation point profile and fat content as well as provide any supplementary nutritional benefits.
Avocado Oil (Smoke Point 520° F)
Avocado Oil has the highest smoke point of any plant oil. Reaching to about 520 degrees, the extremely versatile avocado oil can be used in most high heat cuisine. Containing huge amounts of monosaturated fat, it improves cholesterol numbers which is very beneficial for the heart. Avocado oil also contains lutein, an antioxidant that improves general eye health and improves the absorption of fat–soluble anti-oxidants.
Rice Bran Oil (Smoke Point 490° F)
Rice Bran Oil contains 32% polyunsaturates and 40% monounsaturated which helps lowers cholesterol. It is also free of trans fat and low in saturated fat. Unlike other oils, Rice Bran Oil features 2 unusual components, oryzanol, which blocks absorption of cholesterol in the body, and tocotrienols, a group of related fat-soluble compounds that are converted into vitamin E which is a well-researched antioxidant for the heart. In the kitchen, rice bran oil is very stable and makes it good option for pan-frying.
Extra Virgin Olive Oil (Smoke Point 450° F)
Extra virgin olive oil is the only cooking oil that is made without the use of chemicals and/or industrial refining. It’s simply the juice of fresh, healthy olives which contain antioxidants and healthy fats.
According to the FDA the monounsaturated fat content of olive oil helps reduce the risk of heart disease. The oil also contains polyphenols which act as antioxidants that helps reduce stress in your body.
Olive oil also contains Vitamin E and small amounts of Omega-3 and Omega-6 fatty acids which are all beneficial to the body. Vitamin E is great for the skin while Omega -3 and 6 are essential for brain health.
Almond Oil (Smoke Point 420° F)
Almond oil is not only good for your skin but it is also edible and makes as a great alternative to other cooking oils.
Boasting as one of the best sources of Vitamin E, adding one tablespoon of food grade almond oil into our diet is equivalent to 5 milligrams of vitamin E or about 26% of your daily dietary need.
Almond oil is best for medium heat recipes and features a nutty flavor that adds richness to any recipe you can think of.
Macadamia Oil (Smoke Point 390° F)
Offering a smooth buttery flavor, macadamia oil is one of the most versatile oil there is in the market. It can also be used as a substitute for butter when baking, deep-frying, roasting and as a base for salad dressing.
Having a high smoke point at 390°F, it can be used as a primary oil to have at home. It also contains a high monounsaturated fat content, which are good fats that helps lower cholesterol levels and help the body burn fat more easily.
Coconut Oil (Smoke Point 350° F)
Coconut Oil is one of the best cooking oils there is for high heat cooking. With over 90% of saturated fatty acids, this oil is quite resistant to heat. It also has a long shelf life and you can store it for months and years without it getting spoiled.
Coconut oil also contains Lauric Acid, a form of fatty acid, that can improve cholesterol and help kill bacteria, viruses and fungi. It also helps in slightly boosting metabolism and helps you feel “full” compared to other fats.
Oils to Use With Caution
Not all oils are created equal. While some oils feature health boosting benefits, others oils should be used with caution. Here are some oils we recommend to use sparingly.
Vegetable Shortening (Smoke Point 360° F)
Often used in baking to add more flavor and texture to crust and shells, vegetable shorteners are actually made through a process called hydrogenation. The process transforms liquid vegetable into solid vegetable fat. Although vegetable shortening contains two essential vitamins (vitamin E and K) and unsaturated fat, it doesn’t supply other essential nutrients; its main drawback.
A study done by Harvard School of Public Health suggests that decreasing your saturated fat intake to 7% or less can drastically cut your risk of heart disease. Depending on the calories you consume each day, adding vegetable shortening to your diet can significantly increase saturated fat content in your body. A tablespoon of shortening contains 3.2 grams of saturated fat, which can take huge chunk of the daily recommended intake.
In addition, a tablespoon of vegetable shortening also contains 1.7 grams of trans fats which can raise bad cholesterol levels (LDL) and increase you risk of heart disease. Trans fat, also known as trans fatty acid, is an unhealthy substance produced when oils goes through the chemical process of hydrogenation. Trans fat disrupts the body’s ability to regulate cholesterol.
Unrefined (Smoke Point 320° F) and Refined Soybean Oil (Smoke Point 450° F)
Soybeans are a good source of protein, especially amongst all other plant proteins. However, processing soy at a high temperature can modify some of the proteins and reduce their quality. In the US alone, 90% of the soy produced is genetically modified (GMO) and these crops are regularly sprayed with the herbicide Roundup, which has been linked with everything from cancer to celiac disease to autism.
Moreover, the fatty acids found in soybeans are mostly Omega-6 polyunsaturated fats which we need in certain amounts but should consume in moderation. The source of omega-6 is also highly processed and therefore damaged which promotes chronic inflammation in your body. This in itself can trigger all manner of chronic disease related issues.
Corn Oil Refined (Smoke Point 450° F) Unrefined (Smoke Point 320° F)
Corn oil contains huge amounts of polyunsaturated fatty acids and offers stability against oxidation. When the oil is produced, the process includes removal of free fatty acids in order to create excellent frying qualities, discoloration, digestibility, resistance to smoking and flavor retention.
Most of the corn grown worldwide is genetically modified and as such the consequences of genetically modified corn are not entirely known. Genetically modified corn is relatively new to human and animal diets. However, research by Joel Spiroux de Vendomois published in the “International Journal of Biological Science” in 2009 suggests that consumption of genetically modified corn causes toxicity of the liver, kidneys, adrenal glands, spleen and heart in rats.
Canola Oil (Smoke Point 400° F)
The canola plant is a hybrid version of the rapeseed. Debuting during the Industrial Revolution, rapeseed oil was used to serve as a lubricant to machinery, ships and engines. The use of rapeseed in food has been restricted as it features huge amounts of euric acid. In fact, two –thirds of the omega-9 (monounsaturated) fats in this oil is euric acid.
Some studies have shown that consumption of rapeseed oil in children may increases their risk of Keshan’s disease while animal test have shown signs of cardiotoxicity, renal toxicity or hematological toxicity as well. In addition, most of the Canola oil is genetically modified and heavily processed.
Read the study here: https://www.karger.com/Article/PDF/446704
How to Take Care of Your Cooking Oils
Here’s some of the things you can do to make sure that your cooking oil doesn’t go rancid.
- Don’t buy in bulk. Unless there’s a large family gathering or event, there’s no need to buy large quantities of oil. Buying small quantities ensures you’ll use the oil before it gets spoiled.
- Oils that contain unsaturated fats such as olive, canola and avocado oil should be stored in a cool dry dark place.
- Lids should be kept tightly closed soon after using the oil to avoid rancidity.