Stir-frying is one of the most commonly used techniques in Chinese cooking. The key to making a really good stir-fry is using a very high cooking temperature and cooking the food really quickly. Because stir-frying involves cooking food at high heats, it’s important to choose an oil that has a high smoke point. If you don't, the oil will burn and the whole dish will be ruined.
This is because oil that is heated to its smoke point or higher will actually begin smoking and will start to impart a bitter taste to the food. Furthermore, because the oil is breaking down at a molecular level, it can produce carcinogens, which we all know are bad for you. So using the right oil for your stir-fry is an important first step to a delicious dish.
Highest Smoke Point Oils
Chinese cooks normally use soybean oil, vegetable oil, or peanut oil, all of which have a high smoke point. Peanut oil usually has a pleasant nutty flavor and is suitable not only for stir-frying but also for deep-frying. Canola oil, which has a high smoke point but a neutral flavor, is also a good choice. Other types of oil you can use are corn, soybean, and coconut oil.
Be sure to use an oil that has a smoking point at or above 400 F, including:
- Safflower oil (510 F/265 C)
- Rice bran oil (490 F/260 C)
- Light/refined olive oil (465 F/240 C)
- Soybean oil (450 F/230 C)
- Peanut oil (450 F/230 C)
- Corn oil (450 F/230 C)
- Vegetable oil (400-450 F/ 205-230 C)
- Sunflower oil (440 F/225 C)
- Grapeseed oil (420 F/195 C)
Untraditional Stir-Fry Oils
Although you may not consider it, you can also use olive oil to cook a stir-fry. Nowadays more and more families care about healthy living and thus olive oil has become very popular in their households. Just make sure you don’t confuse this with “extra virgin olive oil.” Extra virgin olive oil has a very low smoke point with a strong flavor making it completely unsuitable for stir-frying.
Another oil that is becoming more popular for stir-frying and deep-frying is grapeseed oil. Grapeseed oil is made from the seeds of grapes after the wine has been pressed. It has a clean flavor and a high smoke point (420 F or 195 C), as well as similar health benefits to olive oil but with a more neutral flavor.
Healthiest Stir-Fry Oils
So which stir-fry oils are the healthiest? Both canola oil and olive oil are low in unhealthy saturated fats and high in healthy monounsaturated fats. Scientists believe monounsaturated fats help to lower bad cholesterol (LDL) which can clog arteries and lead to heart disease or strokes, while they increase the level of good cholesterol (HDL) that removes cholesterol buildup from the arteries.
Grapeseed oil is low in saturated fat and high in polyunsaturated fat, which scientists believe can also help raise HDL levels. Grapeseed oil is also a good source of linoleic acid—a type of essential fatty acid which, like the Omega-3 fatty acids found in salmon, can’t be manufactured by our bodies and must be obtained from food.
Oils to Avoid for Stir-Fry
Besides extra-virgin olive oil, there are other oils that should not be used to stir-fry due to their low smoking points. Sesame oil has a very low smoke point, and although there are some Chinese dishes that use toasted sesame oil to fry the ingredients, such as three cup chicken, it is not recommended for high-heat cooking. You need to be very careful when you heat up toasted sesame oil in a wok—don’t overheat it, otherwise, it will burn and make your dish taste very bitter. Most of the time in Chinese cooking, sesame oil is only used for seasoning or adding to stir-fry dishes at the end of cooking.
Another oil to avoid is flax-seed oil. And don't use butter or shortening to stir-fry—you will never see any Chinese stir-fry recipe include butter, because butter, like some oils, has a much lower smoke point than most cooking oils.
More Stir-fry Tips
The final choice of oils is up to you, and of course price, availability, and personal taste will play a role in your decision. Once you've selected your oil, there are a few tips to keep in mind for a top-notch stir-fry. First, cut up all your ingredients before heating the oil. Once the oil is hot, you'll want to stir fry quickly at a high heat, so having everything ready will make this process go smoothly.
If you are adding meat or poultry, it's a good idea to cook it first and then set it aside; that way you can be sure it's cooked thoroughly. Also, add ingredients based on the amount of time they need to cook. Broccoli, for example, should go into the wok (or pan) before scallions. And make sure to keep your stir-fry moving—if you allow it to sit, you'll end up with something closer to a stew.