Saponification

Saponification is a process of cleaving esters into carboxylate salts and alcohols by the action of aqueous alkali.

These greasy materials, triesters called triglycerides, are usually mixtures derived from diverse fatty acids.

In the traditional saponification, the triglyceride is treated with lye, which cleaves the ester bonds, releasing fatty acid salts (soaps) and glycerol.

This process is more common where the amount of fatty tissue is high and the agents of decomposition are absent or only minutely present.

[3] Soap makers formulate their recipes with a small deficit of lye to account for the unknown deviation of saponification value between their oil batch and laboratory averages.

The neutralization method is used to produce industrial soaps such as those derived from magnesium, the transition metals, and aluminium.

Most early hard soaps were manufactured using animal fats and KOH extracted from wood ash; these were broadly solid.

As in the triglycerides they are formed from[6] the salts of these acids have weaker inter-molecular forces and thus lower melting points.

Saponification can occur in oil paintings over time, causing visible damage and deformation.

[9]: 16 The saponified regions may deform the painting's surface through the formation of visible lumps or protrusions that can scatter light.