"A drop of incense" is made by chemical synthesis, and taking chemical synthetic substances is very harmful to human body, and long-term consumption will damage the liver. Therefore, long-term consumption of "a drop of incense" is harmful to health. "A drop of incense" is a chemical industrial product, which is very harmful to human body after eating, can damage the liver and cause cancer. It only takes one drop to turn a pot of clear water into a chicken-flavored soup, which can be adjusted at any time according to the needs of guests. At present, many roadside shops are using this "seasoning that can obviously improve the taste", among which rice noodle casserole shops, hot pot restaurants and street noodle restaurants are the most commonly used. The so-called three delicacies, spicy and spicy flavors are all produced by "a drop of incense" to induce customers to turn back. The taste of using a drop of incense is similar to that of the original soup, which saves raw materials and is usually mixed with sesame oil. In order to make diners have an appetite, we should first use the sense of smell of diners to make them come uninvited.