Businessmen found in the investigation that there was a factory in a yard near Zhang Gongdi, Hankou, which specialized in producing fake "thousand pages of tofu". The factory started production in April last year. The three security doors in the factory are closed every day, and all the curtains are closed at night when they don't go to work during the day. After receiving the report, the industrial and commercial departments of Dongxihu took advantage of the night to investigate and deal with the tofu factory near Zhang Gongdi. A worker surnamed Zhou confessed that soy protein isolate, soybean oil, modified starch, salt and monosodium glutamate were mixed on site according to a certain proportion, stirred with a blender, then added with ice cubes and pigments to continue stirring, put into a mold box, steamed in a steamer, and finally sealed and packaged.