Fats and Oils: Saturation

Another distinction between fatty acids is whether their molecules are saturated, monounsaturated, or polyunsaturated. A fatty acid molecule consists of carbon, oxygen, and hydrogen atoms arranged (at least in most of the fatty acids in foodstuffs) in a straight chain. Each carbon atom, except those at the ends of the chain, may have two hydrogen atoms linked to it. If two adjacent carbon atoms lack these attached hydrogen atoms, they link to each other in a ‘double bond’, which is less stable than a normal single bond. A double bond is therefore a weak link in the chain, which may easily be undone in a chemical reaction.