Cooking Oils and Smoking Points
Not all fats are the same. The more refined an oil, the higher the smoke point. That’s because refining removes the impurities that can cause the oil to smoke. Did you know that a fat is no longer good for consumption after it has exceeded its smoke point and has begun to break down?
Saturated fats are mainly animal fats and are solid at room temperature. These fats include butter, cheese, whole milk, ice cream, egg yolks, lard and fatty meats. Some plants fats are also high in saturated fats such as coconut oil and palm oils. Saturated fats raise blood cholesterol more than any other food you eat. By using the right oils and fats for the right reasons, you can preserve the healthful benefits. Your foods will not only taste their best, but also be healthy.
These fats can come from both animal and plant products. There are three (3) types:
Monounsaturated Fats – Usually come from seeds or nuts such as avocado, olive, peanut, and canola oils. These fats are liquid at room temperature.
Polyunsaturated Fats – Usually come from vegetables, seeds, or nuts such as corn, safflower, sunflower, soybean, cotton seed, and sesame seeds oils. These fats are liquid at room temperature.
Trans Fatty Acids – Trans fats are produced when liquid oil is made into a solid fat, such as shortening or margarine. This process is called hydrogenation. Trans fats act like saturated fats and can raise your cholesterol level.
Smoking Points of Fats and Oils:
Based on the above classification, the ideal cooking oil should contain higher amounts of monounsaturated and polyunsaturated fats, with a minimal or no saturated fats and trans fats. Different fats and oils have different uses. Each performs best within a certain range of temperature. Some are made for high heat cooking, while others have intense flavors that are best enjoyed by drizzling directly on food.
The smoke point of an oil or fat is the temperature at which it gives off smoke. The smoke point of oil depends to a very large extent on its purity and age at the time of measurement. A simple rule of thumb is that the lighter the color of the oil, the higher its smoke point. When frying, it is important to choose an oil with a very high smoking point. Most foods are fried between the temperatures of 350-450 degrees Fahrenheit so it is best to choose an oil with a smoking point above 400 degrees.
|Fats or oils||Description||Cooking Uses||Types of Fat||Smoke Point Fahrenheit||smoke Point Celsius|
|Almond Oil||Has a subtle toasted almond aroma and flavor.||Used in sauce and stir fry for Asian foods.||Monounsaturated||420||216|
|Avocado Oil||Vibrant green in color with a soft nutty taste and mild avocado aroma. This is a very healthy oil with a profile similar to olive oil. this oil can be used for very high temperature applications.||Stir frying, searing||Monounsaturated||520||271|
|Butter||Whole butter is a mix of fats, milk solids, and moisture derived by churning cream until the oil droplets stick together and can be separated out.||Baking, cooking||Saturated||350||177|
|Butter, (Ghee) clarified||Ghee has a higher smoke point than butter since clarification eliminated the milk solids (which burn at lower temps).||Frying, sautéing||Saturated||375-485 (depending on purity)||190-250 (depending on purity)|
|Canola Oil (rapeseed oil)||A light, golden-colored oil.||Good all-purpose oil . Used in salads and cooking.||Monounsaturated||400||204|
|Coconut Oil||A heavy nearly colorless oil extracted from fresh coconuts.||coatings, confectionary, shortening||Saturated||350||177|
|Corn Oil||A mild medium-yellow color refined oil. Made from the germ of the corn kernel.||Frying, salad dressings, shortening||Polyunsaturated||450||232|
|Cottonseed Oil||Pale-yellow oil that is extracted from the seed of the cotton plant.||Margarine, salad dressings, shortening. Also used for frying.||Polyunsaturated||420||216|
|Grapeseed Oil||Light, medium-yellow oil that is a by-product of wine making.||Excellent choice of cooking oil for sautéing or frying. Also used in salad dressings.||Polyunsaturated||392||200|
|Hazelnut Oil||The nuts are ground and roasted and then pressed in a hydraulic press to extract the delicate oil.||Salad dressings, marinades and baked goods.||Monounsaturated||430||221|
|Lard||The white solid or semi-solid rendered fat of a hog. This was once the most popular cooking and baking fat, but has been replaced by vegetable shortenings.||baking and frying||Saturated||370||182|
|Macadamia Nut Oil||This oil is cold pressed from the decadent macadamia nut, extracting a light oil similar in quality to the finest extra virgin olive oil.||Sauté, pan fry, sear, deep fry, stir fry, grill, broil, baking.||Monounsaturated||390||199|
|Olive Oil||Oils varying weight and may be pale yellow to deep green depending on fruit used and processing.||Cooking, salad dressings, sauté, pan fry, sear, deep fry, stir fry, grill, broil, baking||Monounsaturated||Extra Virgin-320
Virgin – 420
Pomace – 460
Extra Light – 468
|Palm Oil||A yellowish-orange fatty oil obtained especially from the crushed nuts of an African palm.||Cooking, flavoring||Saturated||466||230|
|Peanut Oil||Pale yellow refined oil with a very subtle scent and flavor. Made from pressed steam-cooked peanuts. used primarily Asian cooking.||Frying, cooking, salad dressings||Monounsaturated||450||232|
|Rice Bran Oil||Produced from the rice bran, which is removed from the grain of rice as it is processed.||Frying, sauté, salad dressings, baking, dipping oil||Monounsaturated||490||254|
|Safflower Oil||A golden color with a light texture. Made from the seeds of safflowers.||Margarine, mayonnaise, salad dressings||Polyunsaturated||450||232|
|Sesame Oil||Comes in two types – a light very mild Middle Eastern type and a darker Asian type pressed from toasted sesame seeds.||Cooking, salad dressings||Polyunsaturated||410||232|
|Shortening, Vegetable||Blended oil solidified using various processes, including whipping in air and hydrogenation. May have real or artificial butter flavor added.||Baking, frying||Saturated||360||182|
|Soybean Oil||A fairly heavy oil with a pronounced flavor and aroma.||Margarine, salad dressings, shortening||Polyunsaturated||450||232|
|Sunflower Oil||A light odorless and nearly flavorless oil pressed from sunflower seeds. Pale yellow.||Cooking, margarine, salad dressings, shortening||Polyunsaturated||450||232|
|Vegetable Oil||Made by blending several different refined oils. Designed to have a mild flavor and a high smoke point.||Cooking, salad dressings||Polyunsaturated|
|Walnut Oil||Medium-yellow oil with a nutty flavor and aroma. More perishable than most other oils||Sauté, pan fry, sear, deep fry, stir fry, grill, broil||Monounsaturated||400||204|
Re-using Cooking Oils
I, personally, never reuse cooking oils. The foods you cook the oils in will cause the oils to go rancid faster.
A recent study found that a toxin called 4-hydroxy-trans-2-nonenal (HNE) forms when such oils as canola, corn, soybean and sunflower oils are reheated. Consumption of foods containing HNE from cooking oils has been associated with increased risks of cardiovascular disease, stroke, Parkinson’?s disease, Alzheimer’s disease, Huntington’s disease, various liver disorders, and cancer. Once absorbed in the body, HNE reacts with DNA, RNA and proteins affecting basic cellular processes.
That being said:
Reusing cooking oil has been done for ages. There really isn’t a problem, if done properly. The greatest hazard is allowing the fat to become rancid (spoiled) and deteriorated to the point it produces undesirable flavors and odors. Besides ruining what would have been a perfectly good meal, rancid oils also contain free radicals that are potentially carcinogenic. Rancid oil has fewer antioxidants but is not poisonous.
To re-use oil safely, use these tips:
- Strain it through a few layers of cheesecloth to catch any food particles. Be careful with hot oil, though, because you can easily get burned.
- Shake off excess batter from food before frying it.
- Use a good thermometer to fry foods at 190°C.
- Turn off the heat after you are done cooking. Exposing oil to prolonged heat accelerates rancidity.
- Don’t mix different types of oil.
- Store oil in a cool, dark place.
- Avoid iron or copper pots or pans for frying oil that is to be reused. These metals also accelerate rancidity.
Signs of Deteriorated Oil:
- Oil darkens with use because the oil and food molecules burn when subjected to high/prolonged heat.
- The more you use an oil, the more slowly it will pour. Its viscosity changes because of changes to the oil’s molecular structure.
- Loose absorbent particles accumulate as sediment at the bottom of the storage container or are suspended in the oil.
- When smoke appears on the oils’ surface before the temperature reaches 190 degrees C (375 degrees F), your oil will no longer deep-fry effectively.
- If the oil has a rancid or “off” smell or if it smells like the foods you’ve cooked in it, it should be discarded.
Harvard School of Public Health.
The Culinary Institute of America (1996). The New Professional Chef, 6th edition, John Wiley & Sons