Understanding the Science Behind Cold Process Soap Making
Frequently asked about, let's delve into the science behind cold process soap making.
Cold process soap, the method I use, is a traditional technique involving alkali, water, oils, and butters. These ingredients, though typically not compatible, undergo a chemical process called saponification.
Contrary to its name, the cold process method requires some heat to melt the oils and butters. The lye solution, comprising sodium hydroxide and water, generates its own heat during mixing.
Combining the hot lye solution with oils and butters initiates saponification. This chemical reaction breaks down esters in oils and butters, releasing fatty acids and glycerol, resulting in the formation of soap rich in glycerin.
While essential for soap making, the lye solution is fully consumed during saponification, leaving no sodium hydroxide residue in the final product.
Following saponification, the soap enters the curing stage, where it's left to dry out for 4-6 weeks. During this time, any remaining traces of lye transform into soap, and the water content evaporates, resulting in a harder bar. The longer the curing period, the harder and longer-lasting the soap.
Understanding this process sheds light on the meticulous craftsmanship behind each handmade cold process soap bar.