Handcrafted soaps made from scratch require three ingredients to become soap: oil (animal or vegetable oil, not petroleum-based oil), water and lye.
Today, soaps are made from fats and oils that react with lye (sodium hydroxide). Solid fats like coconut oil, palm oil, tallow (rendered beef fat), or lard (rendered pork fat), are used to form bars of soap that stay hard and resist dissolving in the water left in the soap dish.
Cold process soap is made by mixing fatty acids and sodium hydroxide (lye) together. Fatty acids used in this method can be almost any oil, such as beef tallow, olive oil or hemp oil. Cold process soap making represents a combination of an art and science.
Through the ages soap has been used to cleanse, to cure skin sores, to dye hair, and as a salve or skin ointment. But today we generally use soap as a cleanser .
A look at how soap is made with the science of Chemistry.. Other anionic as well as nonionic surfactants are the main ingredients in today's detergents.