Fatty Acids

Buidling blocks of fat and oil molecules - The structure and composition of fatty acids determine the properties of the respective fats and oils 

All fats and oils have a similar basic structure: They are compounds of the alcohol glycerin and various fatty acids. 

Fatty acids consist of chains of carbon atoms (C) with varying lengths. Depending on the length, they are called short-chain, medium-chain, or long-chain fatty acids. If the carbon atoms in a chain are saturated with bonds to hydrogen atoms, they linked by only single bonds (C-C). They are hence called saturated fatty acids. If hydrogen atoms are missing, double bonds between carbon atoms must be formed. Therefore, carbon chains with at least one double bond are called unsaturated fatty acids (includes omega-3 fatty acids). Unsaturated fatty acids are further divided into mono-unsaturated fatty acids (one double bond) and poly-unsaturated fatty acids (two or more double bonds). The chain length and the number of double bonds determines the biochemical properties of fatty acids.

• Liquid oils contain mainly mono- or poly-unsaturated fatty acids with relatively short chains. Solid fats consist predominantly of long-chain saturated fatty acids. 

• The composition of fatty acids in foods influences the level of cholesterol in the blood. While saturated fatty acids increase the level of cholsterol in the blood, mono- or poly-unsaturated fatty acids can reduce cholesterol levels. 

Vegetable oils consist mostly of mono- or poly-unsaturated fatty acids. Animal fats consist mainly of saturated fatty acids.