Free fatty acids are the most important contributor to quality degradation in oils.
Fatty acids are “acids” because they meet the Bronsted/Lowry definition of an acid
as a compound which donates a hydrogen ion (H+) to another compound called a
base.
When fatty acids dissociate from the glycerin backbone exposing the hydrogen ion
(radical) they become “free fatty acids.”
Because of the activity of the hydrogen ion (radical) and the weak double carbon
bonds, free fatty acids readily combine and recombine in unpredictable and
indefinable ways to form extremely complex polymer networks