According to the oil’s quality, China's edible oil can usually be divided into four grades including first, second, third and fourth grade (level four is the lowest grade), respectively, which are equivalent to the original classification including salad oil, advanced cooking oil, primary grade and secondary grade oil. The unclear expressions on the external packing such as "cooking oil" and “salad oil" without other detailed information will be banned. There are various types of edible oil in the market, however, they will only be divided into two categories that are physical pressure oil and chemical leaching oil if only taking the production process into consideration. These two types are only different in producing method and both safe to eat if they conform with national edible oil quality standards and hygiene standards. The following are several common vegetable oil in the market.
Peanut oil is transparent with light yellow color and fragrance smell, and easy to digest. Peanut oil contains more than 80% unsaturated fatty acids (including 41.2% oleic acid, 37.6% linoleic acid) as well as saturated fatty acids such as palmitic acid, stearic acid, and 19.9% peanut acid.
According to the contents stated above, the composition of fatty acids in peanut oil is good, easy to digest and be absorbed. Besides，peanut oil can help with baby's brain development. If lack of zinc, the baby will has dysplasia and mental retardation, The cephalin, lecithin and choline contained in peanut oil can effectively improve memory and very helpful to baby's intelligence development.
Cooking method: Fried cooking under 200 ℃.
2.The seed oil
Seed oil generally has dark yellow or brown color containing 0.4%～l.0% arachidic acid, 14% ~ 19% oleic acid, 12% ~ 24% linoleic acid, 31% ~ 55% erucic acid and 1% ~ 10% linolenic acid. Considering the nutritional value, the digest absorption rate of seed oil can reach to 99% and is beneficial to gall bladder function. Even under the liver’s pathological conditions, human body can still carry on the normal metabolism of seed oil. However, seed oil is lack of linoleic acid and other must needed fatty acids and the composition of fatty acid is imbalance, so the overall nutritional value is lower than general vegetable oil. In addition, the seed oil contains mass amount of erucic acid and sinalbin, which are generally considered to be the negative factors to body's growth. If eating with high grade cooking oil that is rich in linoleic acid, the nutritional value of seed oil will be increased.
3.The sesame oil
There are two types of sesame oil, common sesame oil and refined grinding sesame oil, which are the oil products made from sesame. The oil extracted from sesame, no matter it is common or refined oil, has the fatty acids containing 35.0% ~ 49.4% oleic acid, 37.7% ~ 48.4% linoleic acid, and 0.4% ~ 1.2% arachidic acid. The digestion and absorption rate of sesame oil can reach to 98%. There is no harmful composition to human body, instead, sesame oil is particularly rich in vitamin E and linoleic acid. Eating sesame oil can adjust the function of blood capillary, enhance organizational absorptive capacity for oxygen, improve blood circulation, promote gonad development and anti-aging. So the sesame oil is the high quality cooking oil that has good edible quality and nutritional value.
4.The cotton seed oil
Refined cotton seed oil generally is in orange yellow or brown color. The fatty acid contains 21.6% ~ 24.8% palmitic acid, 1.9% ~ 2.4% stearic acid, 0 ~ 0.1% arachidic acid, 18.0% ~ 30.7% oleic acid and 14.9% ~ 55.0% linoleic acid. The refined cotton seed oil is edible after removing the toxic materials such as gossypol. Cotton seed oil contains a large amount of essential fatty acids and good to eat with animal fat, because the linolic acid can effectively inhibit the increase of cholesterol in the blood and maintain the healthy condition of human body. The digestion and absorption rate of cotton oil is 98%.
The refined sunflower oil has clear light yellow or greenish yellow color with fragrance scent and pure taste. The composition of fatty acids in sunflower oil is influenced by climatic conditions. Sunflower oil produced in cold area contains 15% oleic acid and 70% linoleic acid, while in warm area it contains 65% oleic acid and 20% linoleic acid. Sunflower oil digestibility rate is 96.5%. It is rich in linoleic acid and have significantly effect to lower cholesterol, prevent hardening of the arteries and coronary heart disease. The proportion of linoleic acid and vitamin E is balanced, which is easy to be absorbed by human body. Thus, sunflower oil has high nutritional value and is good for human health.
Linseed oil is also called siritch. Linseed oil contains 9% ~ ll % saturated fatty acids, 13% ~ 29% oleic acid, 15% ~ 30% linoleic acid and 44% ~ 61% linoleic acid. Linseed oil has a special scent and the quality is lower than peanut oil, sesame oil and sunflower oil. In addition, high percentage of linoleic acid will bring down the storage stability and thermal stability. The nutritional value is also lower than the edible oil that contains high percentage of linoleic acid and oleic acid.
7.Safflower seed oil
Safflower seed oil contains 6% saturated fatty acid, 21% oleic acid and 73% linoleic acid. Due to its main component is linoleic acid, so the safflower has particularly high nutritional value and can prevent the serum cholesterol deposition in the blood vessel walls, good for prevention and treatment of atherosclerosis and benefit the cardiovascular health care. Moreover, safflower seed oil contains large amounts of vitamin E, oryzanol and other medicinal ingredients, so has been hailed as the new "healthy oil" or "healthy and nutritious oil".
The soybean oil has deeper color and lustre with special bean smell. It has low thermal stability and will generate bubbles while heating. Soybean oil contains lots of linoleic acid, easily be oxidized and produce more "bean smell" after oxidative degradation. If considering the edible quality, sesame oil, sunflower oil and peanut oil are better than soybean oil.
From the nutritional value point of view, soybean oil contains 7% ~ 10% palmitic acid, 2% ~ 5% stearic acid, 1% ~ 3% arachidic acid, 22% ~ 30% oleic acid, 50% ~ 60% linoleic acid and 5% ~ 9% linoleic acid. Soybean oil has balanced fatty acid composition and is rich in linoleic acid which can significantly reduce serum cholesterol and prevent cardiovascular disease. Besides, soybean oil contains rich amount of vitamin E, vitamin D and lecithin, which are very beneficial to human body’s health. In addition, the soybean oil’s digestion absorption rate can reach to 98%. Thus it is a good cooking oil with high nutritional value.
Olive oil has yellowish green color with a pleasing aroma and special taste and is still transparent under a low temperature (close to 10 ℃). So the first-round low pressure cold pressed olive oil is an ideal salad oil and cooking oil. In the production process of Olive oil, there isn’t any chemical processing. It contains provitamin A, vitamin D, vitamin E and the total amount of unsaturated fatty acids more than 80% which include more than 86% oleic acid, 1% ~ 5% linoleic acid and 0.9%arachidic acid. The digestive absorption rate can reach to 94%.Compared with corn oil, linoleic acid and vitamin E content is lower. Olive oil contains antioxidants called polyphenols, which can resist heart disease and cancer, and able to aggregate with squalene to slow down the growth of colon and skin cancer cell. As a result, the nutritional value of olive oil is quite high.
10.Rice bran oil
Refining rice bran oil has light yellow color with more than 80% unsaturated fatty acid. The oleic acid content is very high, so the digestion and absorption of rice bran oil is in high level. Except for natural tocopherol (average tocopherol content is 400 mg/kg), it contains squalene and a variety of ferulic acid ester, which can help with antioxidation and reducing blood fat. Rice bran oil is a good quality edible oil.
Walnut oil is rich in phospholipids and essential nutrients to brain, and is greatly benefit to promote the baby's intellectual development and maintain the normal operation of the nervous system function. Walnut oil also contains antioxidants such as squalene and polyphenol, which can help with the growth and development of the baby keeping the bone density, protecting the skin, preventing radiation and enhancing immunity. For infants, it is benefit to balance metabolism and improve the effect of the digestive system.
Cooking method: low temperature cooking or directly use
12.The tea seed oil
Camellia seed oil is one of the traditional woody edible vegetable oil in our country and referred to as the "Oriental olive oil" because the grease of camellia seed oil composition and nutrients are very much similar to olive oil. It can not only lower cholesterol, but also improve the baby’s immunity, enhance the digestive function of the gastrointestinal tract and promote the absorption of calcium which is especially important for babies under growing period. In addition, the camellia oil is close to the nature milk fat of human, so it is a good choice for babies. The vitamin E and antioxidants with tea seed oil can not only prevent disease, also has cosmetic effect for skin care.Cooking method: directly edible.