Saponification is the process during which the fatty acids turn into soap (sodium laurate, myristate, palmate, oleate and linoleate), and the Lye (NaOH or KOH) combines with glycerol oxide in the oils and turns into glycerine.
The amount of lye needed for this to happen is called the SAP value, and is different for each oil, butter or wax. The value is also different for Sodium Hydroxide (NaOH) and Potassium Hydroxide (KOH).
Our Golden Rules:
- Stick to either grams or ounces – don’t mix and match
- Use precise scales – soap making is a precise science
- Calculate the lye needed for each oil and then add them together to give you the total
- Superfat by at least 5% to prevent unsafe ‘Free Caustic Alkali’ in your soap
We recommend you use our downloadable calculator to work out how much lye you will need for you recipe, including adjustments for different water levels and superfatting.