The reaction between the oils and the lye causes the lye to be neutralized. This is called the saponification process. You can find more info about this process through a Google search if you wish to get a more in depth lesson on the chemistry side of soap making.LilyD said:We are making soap for my sister Dawn and she is allergic to pretty much anything that is chemical. She asked if we would make her some goat milk soap that is all natural but all the recipes that I have seen use lye. I just don't want to make a bunch and then have her not be able to use it.