Rapeseed oil is divided into grade one, grade two, grade three and grade four, and grade one.
1, first-class oil and second-class oil are highly refined, and after degumming, deacidification, decoloration and deodorization, they have the characteristics of tasteless, light color, high smoke point, less cooking fume and difficult solidification at low temperature. After refining, the content of harmful components in primary and secondary oils is low, and at the same time, many nutrients are lost;
2. The refining degree of the third-grade oil and the fourth-grade oil is low, and only through simple degumming, deacidification and other procedures. Its color is dark, the smoke point is low, and the oil smoke is large in the cooking process. Due to the low refining degree, the impurity content in the third and fourth grade edible oil is high, and some carotene, chlorophyll, vitamin E and so on are also retained.
3. The purity of primary and secondary oils is high and the impurity content is low, which can be used for cooking at higher temperature, such as stir-frying. Third-and fourth-grade oils are not suitable for high-temperature heating, but can be used to make soups and stews.
Edible guide
1, oil has a certain shelf life, so don't eat oil that has been left for too long.
2, because there are some "green smells", it is not suitable for direct use in cold dishes.
3. Repeated use of oil after high temperature heating should be avoided.
4. The oleic acid content of unsaturated fatty acids in high-quality rapeseed oil is second only to olive oil, with an average content of about 6 1%. In addition, the content of oleic acid and linoleic acid in rapeseed oil, which is beneficial to human body, ranks first among all kinds of vegetable oils. Experts believe that there are many misunderstandings in edible oil consumption of urban and rural residents due to the strong recommendation of foreign grain merchants. Therefore, people should know more about the nutritional characteristics of rapeseed oil and actively advocate the consumption of rapeseed oil.
Rapeseed oil has a certain pungent smell, which is called "green smell" by the people. This smell is caused by a certain amount of glucosinolate in it, but the rapeseed with excellent varieties does not contain this substance.