ISO 1066:1975 Preview
Analysis of soaps -- Determination of glycerol content -- Titrimetric method
This standard was last reviewed and confirmed* in 2016.
*Therefore this version remains current
The determination is carried out in the following way: Decomposition of the soap with sulphuric acid, and extraction of the fatty acids with light petroleum. Oxidation of the glycerol by periodic acid to formic acid and formaldehyde, and titration of the formic acid produced using a pH meter.