Oil smoke is not an odd thing in our cooking work. When heated to certain temperature, the edible oil starts to smoke. And this temperature is called smoke point. Oil smoke could do a lot of damage to people. The irritating cooking smell surrounds us and we have dirty things on our clothes and the wall of the kitchen and such dirt is so difficult to clean. What’s more, oil smoke contains multiple substances that could make people stuck in sickness. One of the harmful substances is acrolein, which will increase cardiovascnlar and cerebrovascular diseases, while the benzpyrene is closely related to lung cancer. When the oil smoke particulate attaches on the skin, the pores will be blocked, accelerating the skin aging. The skin becomes rough and wrinkles, melanin manifolds and turns colored spot.
Smoke point is one of the quality indexes of edible oil. Oil that has lower smoke point is easier to smoke. Different edible oil has different smoke point, while for the same oil, the more refined one has higher smoke point, since the impurities in the crude oil cause the phenomenon of smoking. For unrefined edible oil, the smoke point of peanut oil is 160°C, for soybean oil it is 166°C, and for sesame oil it is 177°C. After refined, the impurities are removed, and their smoke point is almost all above 230°C. The refined oil has shallow color and light favor. At the consumer’s point, purer oil has higher smoke point, and not easily smokes. What is to be paid attention to is that, some beneficial constituents, such as vitamin E and phytosterin, are also removed during the process of refining.