By: Billy BeerSlugger
So I’m taking a shower this morning and I’m in there just suds’n it up with my Irish Spring soap bar and it kind of dawns on me that I’m not really sure how soap works. Yea I know it supposed to get you clean but how and why?
Hopefully you’re taking a shower at least once a day for hygiene purposes but maybe you have run into the same questions I have about soap.
I did some research and here goes my best explanation of the phenomenon known as soap:
Soap is made up of sodium or potassium salts of fatty acids which are gotten when combining common oils or fats with a strong alkaline solution (usually lye) in a process known as saponification. The fats are hydrolyzed by the base, yielding alkali salts of fatty acids (crude soap) and glycerol. Glycerol is a substance found in most bar soaps I’m guessing because it is in my Irish Spring.
Soap is an excellent cleanser because of its ability to act as an emulsifying agent. An emulsifier is capable of dispersing one liquid into another immiscible liquid. This means that while oil (which attracts dirt) doesn’t naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.
Grease and oil are nonpolar and insoluble in water. When soap and soiling oils are mixed, the nonpolar hydrocarbon portion of the micelles break up the nonpolar oil molecules. A different type of micelle then forms, with nonpolar soiling molecules in the center. Thus, grease and oil and the ‘dirt’ attached to them are caught inside the micelle and can be rinsed away. Basically you can get more ball sweat bacteria and facial grease off of you with soap than you can with regular water, which is a good thing.
The earliest users of soap date back to around 2800 BC in Ancient Babylon. There was a found that was recipe written on a clay tablet.
The Ebers papyrus (Egypt, 1550 BC) indicates that ancient Egyptians bathed regularly and combined animal and vegetable oils with alkaline salts to create a soap-like substance. Egyptian documents mention that a soap-like substance was used in the preparation of wool for weaving.