It occurred to me recently that most people probably have no idea what ingredients are used to make soap. Or how readily available they are.
Perfect blog material so here goes.
Soap is made by mixing natural butters and/or oils. (Vegetable or animal based can be used). Water and Sodium Hydroxide also known as lye.
When these are all mixed together a chemical reaction called saponification occurs and when that reaction is complete you will have soap.
What kind of soap you have however depends, to a degree on what butters and oils you use and this is where the variables come in.
So, the simple answer is, for a very basic soap you need oils, water and sodium hydroxide. You can add essential or fragrance oils for scent and other ingredients for colours if you fancy being creative but these are all optional.
So what butters and oils should you use. I am firmly of the opinion that keeping it simple, especially in the early days, is key. For that reason the recipe I use in my soap making workshops uses just 3 , olive oil for mildness, cocoa butter for skin care and to add hardness to the bar, and coconut oil for big bubbles and deep cleaning. These are all readily available, not too expensive and I like to remain palm free in my soap making. I am also a big fan of a simple coconut oil soap. If you would like a recipe for this you can find it here.
The options however are endless and the internet is littered with recipes ranging from basic to exotic so the sky really is the limit. If you needed a very mild gentle bar of soap for example, you would use a recipe that is high in olive oil. A deep cleaning gardeners or mechanics soap would ideally be higher in coconut oil which is great for lifting the dirt but could be too cleansing for a baby's delicate skin.
I am UK based and buy the bulk of my ingredients from online suppliers however there is nothing at all to prevent you using oils purchased from supermarkets or online providing they are pure and not mixed with other oils - this would pose a problem as your recipe would not work properly and may end up lye heavy which would mean your soap is caustic and could burn you.
Lye is readily available from many hardware stores but you do need to endure it is good quality 100% sodium hydroxide and not blended with anything else.
So in a nutshell.
Soap = water + oils + sodium hydroxide. Simples!