Fatty acids are carbon chains with a methyl group at one end of the molecule and a carboxyl group at the other end. The length of carbon chains is usually 16 or 18 carbon atoms.
The C-H bonds in fatty acids are relatively non-polar. This is the reasonfatsmix poorly with water.
Figure 1.Types of fatty acid. a)Saturated fatty acid, b) Unsaturated fatty acid, c) Trans fatty acid