Every time I walk into the supermarket cooking oil section, I hesitate! With so many oils on the shelves—some expensive, some cheap, some dark-colored, some light-colored—which one should I choose? Have you ever been as indecisive as I am? Today, I'll walk you through the dazzling array of cooking oils and how to use them.
Peanut Oil—Stir-frying
"A white house, a red curtain, inside lives a white fatty fellow." "Shandong peanuts" have always enjoyed a high reputation at home and abroad, so the oil pressed from them naturally became one of the main cooking oils for people in Shandong.
Advantages: The fatty acids in peanut oil are relatively well-balanced, and it is also rich in vitamin E, which can reduce the oxidation of unsaturated fatty acids. Overall, peanut oil has a good flavor and decent heat resistance.
Disadvantages: Peanut oil has a relatively high content of omega-6 fatty acids, reaching 37%, but it basically contains no omega-3 fatty acids. Peanuts can easily be contaminated with aflatoxin, which is particularly soluble in oil.
Usage Advice: When buying peanut oil, be sure to choose high-quality products from major brands; try not to buy products from small workshops to prevent excessive aflatoxin. From a cooking perspective, peanut oil is relatively stable and can be used for daily stir-frying, but it is not suitable for high-heat stir-frying or deep-frying. It's worth noting that consuming peanut oil with oils rich in omega-3 fatty acids, such as walnut oil, almond oil, and perilla oil, is more beneficial to health.
Colorful Chicken Cubes
Soybean Oil—Stewing and Boiling
Soybean oil is processed from soybeans and is mainly produced in the Northeast, North, and East China regions.
Advantages: In soybean oil, linoleic acid is absolutely dominant, with a small amount of alpha-linolenic acid and very little saturated fatty acid. While linoleic acid has a limited effect on reducing the risk of heart disease, alpha-linolenic acid is more beneficial. Clinical nutritional experiments have confirmed that in addition to high cholesterol, the other two risk factors for coronary heart disease are high blood pressure and vascular embolism, and linolenic acid can help reduce these two factors. Soybean oil is rich in vitamin E, and its pale yellow color comes from a small amount of carotene.
Disadvantages: Since both linoleic acid and alpha-linolenic acid are not heat-resistant, especially alpha-linolenic acid, they can easily oxidize and polymerize after frying or repeated heating, which is very harmful to health.
Usage Advice: Soybean oil is best used for low-temperature cooking, such as for pastries, soups, stews, and fillings; it is not suitable for frying food at high temperatures for long periods. The fatty acid composition of corn oil, sunflower oil, and wheat germ oil is similar to that of soybean oil. If you eat a lot of soy products in your daily diet, you have already consumed substances from soy products, and your intake of polyunsaturated fatty acids is sufficient. Therefore, there is no need to use soybean oil, sunflower oil, or corn oil for cooking every day. You can use oils with more monounsaturated fatty acids, such as olive oil, tea seed oil, peanut oil, and rice bran oil, for cooking.
Chicken and Mushroom Stew
Flaxseed Oil—For Cold Dishes
Flaxseed oil, also known as linseed oil, is oil extracted from the seeds of the flax plant. Flax thrives in cold climates and is suitable for growing in regions like Shaanxi, Gansu, and Ningxia. Flaxseed oil is an ancient vegetable oil, and the character "胡" (hú) in its name refers to the ethnic minorities and regions in Northwest China.
Advantages: The essential fatty acid alpha-linolenic acid in flaxseed oil accounts for over 50%, far higher than the 5% in deep-sea fish oil and the 6%-12% in walnuts and pine nuts, earning it the nickname "land fish oil." Alpha-linolenic acid is an omega-3 fatty acid that can be converted in the human body into EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). These can reach the cell membranes of brain cells, the retina, and rod cells, accelerating the directional transmission of bioelectrical impulses in the brain, which is beneficial for thinking and increases memory capacity. Therefore, alpha-linolenic acid can enhance intelligence, memory, logical thinking skills, and protect eyesight. It can also regulate abnormal blood lipids, inhibit platelet aggregation, prevent thrombosis, and inhibit the production and metastasis of cancer cells.
Disadvantages: Flaxseed oil is prone to oxidation and polymerization and is the least heat-resistant of all the oils.
Usage Advice: Children, pregnant and postpartum women, and the elderly can choose flaxseed oil appropriately, as it is beneficial for intellectual development and delaying memory decline. Due to its high level of unsaturation, flaxseed oil should be consumed quickly after opening and is best used for cold dishes.
Cold-dressed Kelp Strips
Rapeseed Oil—Choose "Double-Low" Products
The golden yellow rapeseed flowers are always the most beautiful scenery in the south. Besides being admired for their beauty, rapeseed has a very high oil yield, making rapeseed oil a common vegetable oil for people in southern China.
Advantages: Regarding the nutritional value of rapeseed oil, Professor Wei Liping from the Hospital of Integrated Chinese and Western Medicine, Southern Medical University, says that first, its fatty acid composition is the closest to the human body's needs. Low-erucic acid rapeseed oil has low saturated fat content and high oleic acid content, and its proportion of the essential fatty acid alpha-linolenic acid is second only to flaxseed oil. Secondly, rapeseed oil contains beneficial phytosterols, which have physiological functions such as lowering cholesterol, reducing cardiovascular diseases, and preventing cancer. Finally, it has a high content of polyphenols, which have biological activities such as lowering cholesterol, scavenging free radicals, and anti-tumor effects, and are a source of natural antioxidants. In addition, rapeseed oil is also rich in vitamin E, carotenoids, and trace elements like selenium and iron.
Disadvantages: Professor Wei Liping says that some studies have pointed out that erucic acid in rapeseed oil is harmful to the human body and can increase cholesterol in animal kidneys; long-term intake can affect growth and development. The rapeseed oil we used to eat was the traditional "double-high" (high erucic acid, high glucosinolate) oil. After continuous research and breeding, the quality of rapeseed has now been improved to "double-low," meaning low erucic acid and low glucosinolate content. Therefore, we no longer need to worry about high erucic acid when consuming rapeseed oil.
Usage Advice: Rapeseed oil should be consumed as soon as possible after opening. If left for too long, its polyunsaturated fatty acids can easily be oxidized and damaged by oxygen in the air, producing substances that are harmful to the human body. Fortunately, rapeseed oil is rich in vitamin E, which enhances its antioxidant properties, protecting various unsaturated fatty acids from oxidation and spoilage. However, it is still advisable to buy small bottles and finish them quickly.
Fermented Black Bean Stir-fried Beans
Tea Seed Oil—An Alternative to Olive Oil
Tea seed oil, also known as camellia oil, is extracted from the seeds of the tea plant. In the hilly areas of Hunan, Jiangxi, and other places, the mountains are covered with tea plants, and tea seed oil has almost become a beautiful symbol of the local culture in Central and Southern China.
Advantages: The unsaturated fatty acids in tea seed oil are as high as 85%-97%, higher than in any other oil. Moreover, its oleic acid content (a monounsaturated fatty acid that helps lower "bad" cholesterol in the blood and raise "good" cholesterol, which is beneficial for controlling blood lipids) is around 80%, even higher than that of olive oil. In terms of nutritional value and health functions, tea seed oil is no inferior to olive oil, and it is cheaper, making it a great value for money, hence it is also known as "Oriental olive oil." Tea seed oil has good heat resistance.
Disadvantages: The polyunsaturated fatty acid content in tea seed oil is relatively low.
Usage Advice: Currently, some small-scale oil pressing workshops use traditional hot-pressing methods, which may have problems such as high impurity content, significant nutrient loss, and being prone to mold. It is recommended to purchase tea seed oil from major brands whenever possible. Tea seed oil is suitable for daily stir-frying and can also be used in cold dishes. It is best to pair tea seed oil with oils rich in polyunsaturated fatty acids, such as soybean oil and corn oil.
Guangxi Sour Bamboo Shoots with Soy Sauce Pork