Edible oil, which comes from animal fat or vegetable oil, is an indispensable nutrient in people’s daily life. The content of essential fatty acids in animal fat is less, and the nutritional value is lower; the content of unsaturated fatty acids in vegetable oil is more, and the melting point is lower, so the human body has high digestibility for it, and the nutritional value is higher due to the content of essential fatty acids. Therefore, we advocate vegetable oil as the main cooking oil in our life, but no matter which kind of oil we use, we should avoid high temperature heating.
Because the fat is heated by high temperature, the fat soluble vitamins, such as vitamin A, carotene and vitamin E, are destroyed, reducing the nutritional value of edible oil. However, please rest assured that the temperature of oil heating will not be too high, and the time is very short, which has no significant effect on the nutrition. However, in the food industry, the cooking oil used for fried food is repeatedly heated at high temperature. When heated, the temperature is high and the time is long. It will not only lose nutrients, but also produce toxic substances. The reason is that high temperature makes the fatty acids of oil polymerize, such as unsaturated linoleic acid and linolenic acid. After heating, the polymerization reaction takes place, forming monomers, dimers, trimers and other compounds. Studies have proved that the human body can not absorb and utilize its trimer, and other trimers are toxic to human body. When they enter the human body, they can cause stagnation of human growth, hepatomegaly, and even cancer. In particular, the repeated high-temperature heating of oil appears more polymers, which is more harmful to the body.
It can be seen that the food that has been repeatedly fried in our life should not be eaten more, such as fried oil sticks, fried sesame and other fried flavor snacks, and it is necessary to avoid regular food and more food, especially the operator should change oil frequently when frying food, and the one that should be poured out must be poured out, and the oil should not be repeatedly heated and used.