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Saponification 101

"What soap is to the body, laughter is to the soul"

-Old Yiddish Proverb



Forget throwback Thursday because we're going way, way back. The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BC in ancient Babylon. The Ebers papyrus (Egypt, 1550 BC) indicates the ancient Egyptians bathed regularly and combined animal and vegetable oils with alkaline salts to create a soap-like substance. The word "soap" is a Roman word possibly deriving from a mythical place called Mt. Sapo, which is the Latin word for soap. This word first appeared in Pliny the Elder's Historia Naturalis. Soap and soap-like substances have been made for thousands of years from the Middle East to Europe to Africa to China. American colonial settlers brought their knowledge of soap making over to the "new world" and used wood ash from cooking fires to make a crude soap. Soap making today is just a modern spin on an ancient craft that's been around forever.


Like thousands of years ago, soap is still produced today by combing oils, butters, and fats with an alkaline material such as lye (sodium hydroxide) or potash (potassium hydroxide) and water. It's an acid-base reaction. Combining fatty acids with lye or potash and water is called saponification. If combined in the right proportions, a chemical reaction produces a salt (soap), water, and glycerin. When made correctly, soap does not contain any lye or potash in the finished product because it's all been chemically converted to a skin-safe soap. All soap is made with lye or potash. If someone tells you that they don't use lye or potash in their soap it's because they didn't produce it themselves, acquired it already made, and someone else produced it for them. 


Hand crafted soap is naturally rich in glycerin, a humectant that draws moisture to the skin. Folks will likely find themselves needing and using less lotion when switching to hand-made soap because of this. Commercial soaps are often stripped of their glycerin so that it can be sold separately at a premium price. While this makes the soap harder than hand made, it makes it harsher and drying to the skin. This is one of many reasons that hand made soap is just better.

There are a few different ways to hand-make soap. The Tree Hugger Soap Company® likes to use the cold-process method for their bar soap where less heat is applied to the mixture and the soap is poured into molds to completely saponify over a matter of days. Our bars are left to harden, or "cure" for several weeks.

This patient waiting makes for a harder, longer lasting bar that is gentle with a good lather. Our signature shea butter recipe cures for a minimum of a month, while our castile soaps which are entirely organic olive oil, must cure for 3 months because they contain no "hard" oils. Dang, that's a long time to wait,

but it's worth it. Each oil, fat, and butter saponifies differently and has different properties so combining a blend of well-balanced oils and butters makes for a good bar of soap and happy, grateful skin. 

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