Every time I make soap and mention my “lye water solution” I get questions about the lye.
All soap is made with sodium hydroxide, which is known as lye. Soap cannot be made without it.
People seem to think that melt & pour soap is not made with lye, because you’re just melting down the soap, adding fragrance, additives and pouring into a mold. But the truth is the manufacturer who made and is selling you the melt & pour soap base, has already made the soap go through the saponification stage with the lye. You are just getting the soap after it has saponified and all the oils have turned into soap, and now you don’t have to handle the lye. And since it was previously cured, you technically don’t even need to let the melt and pour soap cure, either.
The manufacturer of melt & pour soap mixes all their ingredients together – their oils and lye, lets the soap go through the saponification stage (where the oils turn into soap), they pour the soap into molds (usually blocks to be resold), and let the soap cure, and then they ship it out to you, however many months later. Then when you get it, you just melt it down and do what you want with it. But it was manufactured with lye because soap can’t be made without lye.
Lye is what causes the oils to turn into soap. No lye remains in the final soap, but it is required to make it.
Every soap you see in stores, markets, online, wherever… has been made with lye.
So the answer to the question regarding “do all of my soaps contain lye” – my soaps are made with lye, but no lye remains in the final soap. Within 24-48 hours after pouring the soap, no lye remains in it. The lye is used up in the saponification process.
So that’s the scoop on lye, and that is no lie.