I get questions all the time about what we use to make soap. I've had people ask me for soap without lye. So, I thought I would do a series about that, since lye sounds kind of scary.
I hated chemistry in high school. No offence, but I have always been that girl who has to see it to believe it, and atoms, and electrons just don't make sense in my head. When I started learning to make soap a few years ago, I had to go back and restudy all of the chemistry to understand what I was doing. Even natural soaps have chemistry.
Sodium hydroxide or lye chemically changes in the presence of oil and butter. It creates heat and binds with the oils eventually becoming a solid mass we know as soap. When formulating a recipe, you have to take into account the properties of the oils and how they will react with the lye, as well has how much oil will be left over after the reaction. You want to have just the right amount left over at the end of the process known as saponification. If you don't have lye, then all you will have is a pot of oil and that isn't soap.
More next week in part 2 of What's in a soap.