FATTY ACIDS
- They are monocarboxylic organic acids (R.COOH) having a hydrocarbon chain of 4 - 30 carbon atoms.
- The polar carboxylic group is hydrophilic (Gk. hydro - water, phillic - to love) or water soluble.
- The remaining part of fatty acid, that is hydrocarbon chain is however nonpolar, hydrophobic (Gk. hydro - water, phobes- fear) or water insoluble.
- It is soluble in fat solvents and is, therefore, lipophilic.
- Substances like fatty acids which have both hydrophilic and hydrophobic components are called amphipathic.
- Fatty acids reduce surface tension of water; increase its wetting power and hence capacity to clean. Soap action in due to this phenomenon.
- Depending upon the absence or presence of double bonds, fatty acids are of two types-
(i) Saturated (ii) Unsaturated