Each fat molecule is composed of one glycerol and three fatty acid molecules. These molecules are also known as lipids, and while they can provide essential nutrients, over-consumption of lipids can have adverse effects on a person's health, notes the University of Massachusetts.
The University of Washington notes that the fat molecule is generated by condensation reactions that bond the three hydroxyls of glycerol to the carboxyl groups of the fatty acids via ester linkages. Due to this, these fat molecules are also known as triglycerides.
The degree of saturation of the hydrocarbon tails within the fatty acids determines the state of the fat molecule. If the fatty acid chains are saturated, containing only single bonds, they allow the compact packaging of the fat molecules. Consequently, like butter, these fats are solids at room temperature. In contrast, the hydrocarbon tails of unsaturated fatty acids are kinked due to the presence of double or triple bonds.
An example of such a fat is oil, which is liquid at room temperature. Although food scientists use the words “fats,” “oils” and “lipids” interchangeably, the term “fat” may be used for solid fat, “oil” for liquid fat and “lipid” for both solid and liquid fat, according to the University of Massachusetts. This distinction of terms ensures clarity.