Sodium Hydroxide

It can't be denied that by itself, Sodium Hydroxide is neither soothing or skin loving, however it is a necessary part of the soapmaking process. Despite what people may claim, you can't make soap without Sodium Hydroxide (also known as caustic soda). Soapmaking begins with melted oils, and by adding a mixture of Sodium Hydroxide and water, a chemical reaction is started, called Saponification. The result of this reaction is soap, which is actually a salt.

So although caustic soda is used as an ingredient in the initial stages of soapmaking, there is absolutely none left in any self respecting bar of soap, because it has all been used up by the chemical reaction of saponification. React A with B and you end up with C - soapmaking works on this principle - the act of causing the chemical reaction changes the original ingredients and creates something completely new. In this case - Soap!

A correct recipe is essential for any soapmaker, and every batch is measured out in minute detail, always making sure there is more oil in the recipe than called for. This is called super-fatting, and makes sure the caustic soda is fully activated and used up as well as adding extra moisturising benefits to the soap because of the extra oil content.