Any of a class of lipids consisting of various saturated
or unsaturated, monobasic organic acids, generally
R.COOH, usually in a straight chain. Chain length
ranges from one hydrogen atom (methanoic, or formic,
acid HCOOH) to nearly 30 carbon atoms.
fatty acids (more than 8-10 carbon atoms) most commonly
occurs as constituents of certain lipids, notably
glycerides, phospholipids, sterols, and waxes, in
which they are esterified with alcohols.
chain fatty acids generally have an even number of
carbon atoms; unbranched chains predominate over branched
chains. They may be saturated (e.g., palmitic hexadecanoic)
acid and stearic or unsaturated, with one double bond
(e.g. oleic cis-octodec-9-enoic-acid) or two or more
double bonds, in which case they are called polyunsaturated
fatty acids(e.g., linoleic acid and linolenic acid)
Short chain acids are pungent liquids, soluble in
As chain length increases, melting points
are raised and water-solubility decreases.