Sanxiang Tea Museum has a Qing Dynasty made of wood "horizontal wedge press", this is the most primitive of the press machine. As industry advances, the power of the press shifts from manual to hydraulic and then electric. Now, the "squeeze mill" in the countryside is powered by electricity. Almost every village in the tea tree producing area has this kind of "soil squeezing workshop". Most of the tea seeds in China are squeezed out of these scattered soil mills, and the people in the oil industry call the "oil" produced by the soil". The sanitary conditions of these earthen workshops cannot be guaranteed, and the inspection and selection of tea seeds can only be done with the naked eye and human hands. Therefore, mixed impurities in tea seed, such as dust, gravel, dirt, waste dregs...... They will stir fry with the tea seed, steam and press, so the pressed oil is the product that does not meet the national food hygiene and safety standards. In accordance with the national food safety law, soil oil can not be sold directly.
However, on the question of soil oil, the food safety law was completely ineffective。 Not only tea, peanut oil, sesame oil, soil and soil etc。 Everfount every day from the farmers market in the press press, sold directly to consumers; the soil is often the virgin square neighbors, industrial and commercial law enforcement。
More seriously, the vast majority of soil oil benzopyrene content exceeded. Benzopyrene is a carcinogen, mainly exists in high temperature flue gas generated in the international agency for research on cancer (IARC) for the assessment of carcinogenic benzopyrene: the evidence is sufficient, as initiating activity. There are two reasons for the excessive amount of benzo pyrene in soil oil. First, there is no refining technology in the soil pressing room; two, in order to improve the oil production rate, the local workshops will stir the tea seed to 150 degrees or higher. However, camellia seed temperature higher than 60 degrees, will produce benzopyrene -! In fact, the high temperature can not only increase the oil yield, but also make tea oil more fragrant. The smell of tea from the tea seed starch in the Maillard reaction, fand generated after heating. Maillard put it plainly, that is, fried foods zoom yellow process. As the starch and fat zoom yellow, the fragrance comes out. That's why roast mutton smells better than boiled mutton. However, benzopyrene also follows these scents, so a healthy diet will avoid over frying.
"But cancer does not happen right away, and the people don't understand it。" Zhou Xinping is a real expert on benzopyrene。 Not only did he learn chemistry, but also because he almost made benzopyrene turn over!
Benzopyrene is not only produced in the process of frying heat。 Picked fresh Camellia fruit first exposure, so that the outer shell burst, after the shell to press。 Now many villages are paved with asphalt road, Camellia fruit on the road drying。 Asphalt contains a large amount of benzopyrene, camellia oil may be stained when drying。 The camellia seed oil from pressure, benzopyrene is easy to exceed the standard。