Here is a how it's made series about soap.
How is our soap made?
All soap is the result of a chemical reaction called the saponification process, that occurs between a lye solution and a fat or oil (such as Sweet Almond Oil or Coconut Oil). After the lye water and oils are combined, soap makers pour soap into moulds. It takes 24 - 48 hours for soap batter to saponify and enter the gel phase. During this time soap gets hot, up to 180°F. Once removed from the soap mould, it drys for an additional 24 hours before being cut into individual bars of soap.
Cold processed soap, in particular, allows the lye mixture to be neutralised without any outside sources of heat, called “curing”. This is quite a time-consuming process that allows for gradual saponification. It can take 3-6 weeks for the soap to cure. The lack of heat keeps the essential oils intact and in perfect condition to lather you in therapeutic goodness.
When you cold process soap, the fatty acid of the oils are broken down by the caustic soda (lye). They then form a chain which on one end loves water and on another end loves oil. You can see these chains in action while you’re lathering up. The oil-loving end grabs on to the dirt and grime, and the water-loving end hangs on to the water that rinses it all away.
On top of the oils necessary for soap making, we also plump up our soap with extra vegetable-based fats to ensure there is plenty left to remove any remaining lye. The extra fat or “super fat” remains intact, providing the moisturising qualities we all love.
What is Cold Process Soap?
Cold process soap is a method of producing soap that requires no extra heat to create the soap - it is therefore ‘cold'. That doesn't mean that things don't get hot - the combination of lye with natural butters and oils create its own heat. A chemical reaction between the ingredients takes place, leaving you, quite magically, with a block of soap. Making soap is definitely both art and science. We use the cold process method at Dorović to preserve the benefits of plant-derived oils and butters.