Cold process soap making is a combinations of an art and science. The condensed version of this type of soap making is that there is a certain proportion of lye (sodium hydroxide) and water to fatty acids that forms a chemical reaction called “saponifaction.” During saponification, the oils and lye mix and become soap – the process takes approximately six weeks to fully complete.

Technically, all hand made soap is “Glycerin Soap.” In many commercial soaps, all the extra glycerin (formed naturally by the cold process soap making method) is harvested out. Thus, all handmade soap is glycerin rich (since hand made soap makers don’t harvest out glycerin in their soap).

There are variations on the cold process method. Hot process soap is an interesting take on the cold process method. The simple explanation is that you take all your ingredients, and add them to a pot (that is then placed over a heat source, such as a stove) and stir frequently until the soap goes through various stages.

Rebatching is another form of cold process soap making. You make your cold process soap from scratch, grate it up, place it over a heat source, in a kettle, with a little liquid (water works very well), and the mixture melts down into a mushy mess that you add colorant and fragrance too. This method is often used to preserve the scent or the healing properties of some essential oils.