Soap Making Process: From Wood Ashes to Animal Fat

The History of Soap Making

Soap was made from wood ashes and animal fat. I don't think it was a specific animal.

Final answer: Soap was historically made by boiling animal fats with potassium carbonate derived from wood ashes. The process yields glycerol and salts of fatty acids known as soaps, with the example of sodium stearate provided. These soaps can emulsify/dissolve fats and oils due to their hydrophilic heads and hydrophobic tails.

Explanation: Soap was traditionally made by boiling fats with a strongly basic solution made by leaching potassium carbonate, K₂CO₃, from wood ashes with hot water. This process involves treating animal fats, which contain polyesters of fatty acids (long-chain carboxylic acids), with a base like potassium carbonate or sodium hydroxide. The end products are glycerol and salts of fatty acids such as palmitic, oleic, and stearic acid, the latter of which are known as soaps. For instance, the sodium salt of stearic acid, sodium stearate, has the formula C₁7H35CO₂Na. Soaps have the ability to emulsify or dissolve lipids, fats, and oils due to their dual nature: their hydrophilic (water-loving) heads interact with water, and their hydrophobic (water-repelling) tails interact with the fats and oils.

What was historically used to make soap?

Animal fats were historically used to make soap, together with potassium carbonate derived from wood ashes.