Alum contains aluminum ions, which hydrolyze into aluminum hydroxide. Aluminum hydroxide is a very good surfactant, which can form a film on the surface of vermicelli, which is beneficial to the loosening of vermicelli. At the same time, aluminum hydroxide has strong flocculation. As a result, fans become very energetic.
Alum has good flocculation effect and is often used as a water purifier among the people. Regular water plants in modern big cities do not use alum, but some small water plants that use surface water sometimes add some aluminum salt flocculants to the water to accelerate the sedimentation of sediment and other suspended matter in the water, making the tap water contain more aluminum. ion.
Alum is often added to some starchy foods such as vermicelli, vermicelli, vermicelli, jelly, jelly, etc. during production. After the flocculation effect of alum, the vermicelli and jelly will become very chewy and will not be easily cooked in boiling water.
