I know nothing about making soap, but want to learn. I would like to understand the process.
Making soap is pretty much
the same, no matter which type of fats/oils is used. Oils are mixed with a lye solution and stirred at a warm temperature.
This initiates a chemical reaction called saponification, which uses up the lye and transforms the triglicerides in the oils
into soap. Each oil has molecules of a different lengths, and therefore requires a particular amount of lye (sodium hydroxide)
to convert all
of its molecules to soap molecules, leaving no lye residue. The amount of lye required for each oil is expressed
as a SAP value.
Normally, you only want to saponify 95% or so of the oil, leaving a small quantity behind so that its emollient
or humectant or other
properties can be preserved to help nourish and condition the skin. This is achieved by calculating a lye
discount. There are dozens
and dozens of soapmaking lye calculators available online. They will do the math and tell you
exactly how much lye to use.
As you get more experienced you’ll learn to do the math yourself.