Pressing and leaching are two methods of camellia oil extraction. Pressing method is to use physical pressing method, so the name means is by pressing, extreme pressure and production of oil, such as we take a pine seed, sunflower seeds hard pressure on a thin paper, will soon find that the paper is soaked with oil, and we buy oil is machine pressed, this oil due to the process is simple, the oil rate is low, at the same time, the nutritional maximization is preserved, so that this oil is better oil, the price is also slightly more expensive, but also the oil is more expensive. It is also slightly more expensive. Leaching is a method of extracting camellia oil from camellia seeds with edible grade solvents using physicochemical principles.
Since the oil yield of the pressing method is very low, so the common businessmen will use the two methods mentioned above to complement each other, that is, after the oil tea seeds are pressed to obtain the "pressed crude tea oil", the residual tea oil in the "oil cake", and then extracted by leaching to obtain the "leached crude tea oil", to obtain the "leached crude tea oil", and the "leached crude tea oil". The oil can be extracted from the oil cake, and then extracted by leaching method to obtain "leaching crude tea oil".
The benzo(a)pyrene exceeds the standard should appear in this link. In order to improve the oil yield, farmers may repeatedly bake and steam the tea seeds, such as temperature control is not good, it is easy to lead to the phenomenon of scorching, generation of benzo(a)pyrene, residue in the shell of the tea seeds; and after the pressing of benzo(a)pyrene residue in all the tea cake, in the extraction of residual oil in the tea cake, residual benzo(a)pyrene is also extracted out, through high temperature and solvent oil chemical reaction, ultimately leading to the leaching of the crude tea oil content of benzo(a)pyrene. The content of benzo(a)pyrene in the leached tea oil is increasing.