Sodium hydroxide, also known as Caustic Soda or Lye, is a product that is used in the creation of soap, detergent, paper, textiles and drinking water. It is a chemical base and comes packaged as a white solid.
Soap – Typically for cold-process soap making, lye is essential. It can also be used in hot-process soap making when mixed with the appropriate fat and oils. Caustic soda (lye) creates a chemical reaction known as saponificiation. This process is what breaks down the oils and turns them into soap.