Soap is a salt of a fatty acid. Soap is mainly made by two processes:
- SAPONIFICATION: the reaction of Neutral Oil with Alkali (i.e. Caustic Soda)
Vegetable Oils / Animal Fats + Caustic Soda = Soap + Glycerin.
- NEUTRALIZATION: the reaction of a Fatty Acid with Alkali (i.e. Caustic Soda)
Fatty Acids + Caustic Soda = Soap + Water.
Neutral Oils are composed by triglycerides: Fatty Acids and Glycerin. The fatty acids used in soap manufacturing have carbon chains composed from 8 to 20 carbons.
Soap produced using Neutral Oils (Vegetable Oils / Animal Fats) as raw materials contains some points of glycerine; soap produced using Fatty Acids as raw materials does not contains glycerine.