A lot of people ask me “How can homemade soap be gentle and good for your skin if it’s made with lye.” “Isn’t that caustic soda? .. The stuff you clean drains with?”
Yes it is! BUT it is impossible to make real soap without it.
First off, I want to give you a brief overview of exactly what soap is.
Soap is an alkali (like lye, aka sodium hydroxide) combined with fats. Together they go through a reaction called “saponification”, and the end result is soap. So, by the very definition of “soap”, you cannot have soap without lye.
Every oil needs a certain amount of lye to turn it into soap, all Aoraki Naturals’ soaps use more oil than is required, which means some of the oils are left behind and all of the lye is well and truly used up. This process is called “superfatting”. It ensures a skin-safe, gentle product and your skin benefits from the moisturising properties of the “unused” oils.
So why does “lye soap” have a reputation of being harsh? In days past, homemakers made soap using lye made from wood ash. Sophisticated scales for measuring were not available and often too much lye was used. When saponification occurred, some lye was left in the soap, making it harsh on the skin.
Hopefully that helps ease any worries you have with lye as an ingredient – remember every bar of soap you’ve used in your life started with a lye solution.