How do you make soap?
All soap is made through the saponification process. Oils/fat and lye (sodium hyroxide) react and create soap. It is important to calculate the correct amount of lye needed based on the sap value for the fats in your soap. The sap value is the amount of lye needed to saponify your oils and turn them into soap. Each oil (such as olive, palm, or coconut) has a different sap value.
Once the calculations are done, you must mix the lye and and water together. Lye and water react and release heat has well as fumes. I often mix the lye and water
outside and I always wear eye protection. It is important to always add lye to water. Never add water to lye. I'm told the reaction is much more violent when reversed. While the lye/waters cools, it is time to melt the oils.
The oils are always melted in a stainless steel pan as lye will react with other metals. The oils melt slowly at a low temperature. In this photo I am melting coconut and palm oils.
When the solid oils are melted, I add the olive oil. The olive oil is
added last, so that it not subjected to any extra heat. It also helps to cool down the other oils. This is important as it is best to mix the lye and oils when they are at a similar temperature. I use a candy making thermometer to test temperatures.
When the temperatures are close, I add the lye to the oils and begin stirring. The mixture starts off clear and slowly begin to get more opaque. It also starts to thicken as the reaction begins.
Here, you can see that the oils are not clear any longer. Soap can be mixed by hand using a spatula, but this can take as long as an hour or more. Often I will mix by hand until the mixture starts to look like soap and then I will take the immersion blender out.
The immersion blender mixes at a much higher speed and it allows the soap to be ready in a matter of minutes. When the soap is ready, it traces. That mean it is thick enough that when you pour a spoonful back in, it will float on top and not sink back in like a liquid. It is an almost pudding like consistency.
When the soap traces, it is time to add the essential oils and herbs to scent and/or color it. This must be done quickly because the soap is beginning to get thicker. The essential oils are not added earlier because the stirring and pure lye (before a reaction has started) would likely destroy the scents.
One everything is mixed thoroughly, I pour it into the mold. The soap mold is lined with freezer paper so that I can easily remove the soap log in a few days. I will generally wrap the soap in a blanket to insula
te it. This helps keep it warm while the saponification reaction takes place.
After 2 days, I will remove the soap log from the mold. I'll usually leave it out of the mold for a few hours to harden up and then I will slice it into bars.
The bars need to cure for another 6-8 weeks while the saponification reaction continues. Two months later, the soap is ready to use!