In theory, you can make soap by treating almost any fat or oil with sodium hydroxide or potassium hydroxide (for a 'soft' soap). Some recipes use animal fats like tallow (from beef) or lard (from pork). Others use vegetable oils, like coconut or olive oil. Soapmaking (or saponification as the chemical reaction is called), like any chemical experiment, is sensitive to the purity of the reactants, the reaction conditions used and the care with which you carry it out.

Making soap on Capraia 

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