ISO 29822:2009 specifies the determination of the degree of isomerization of diacylglycerols in vegetable fats and oils. 1,2-Diacylglycerols are transformed to the more stable 1,3-isomers during storage or due to acidic catalysed reaction.
The mass fraction of 1,2-diacylglycerols can be used as a quality criterion for vegetable fats and oils.