Glycerides

Glycerides are a family of esters formed from glycerol and fatty acids. The glycerol backbone has three hydroxyl groups, and each can be esterified with a fatty acid, yielding monoacylglycerols (one fatty acid), diacylglycerols (two), or triacylglycerols (three). The term glyceride generally refers to any member of this family.

Triacylglycerols, also called triglycerides or neutral fats, are the main storage form of lipids in animals and plants. They are hydrophobic and insoluble in water, allowing them to pack densely in adipose tissue for long-term energy storage. During digestion or mobilization, lipases hydrolyze triacylglycerols to glycerol and free fatty acids, which can be used by cells for energy through beta-oxidation and glycolytic pathways.

Mono- and diacylglycerols occur naturally in many foods and are also produced industrially. They function as emulsifiers and processing aids in the food industry, helping to stabilize mixtures of oil and water and to influence texture and shelf life. They can be formed by partial hydrolysis of triglycerides or by direct esterification of glycerol with fatty acids.

Biosynthesis of glycerides involves enzymatic esterification of glycerol with fatty acyl-CoA derivatives. Their composition—types and chain lengths of the fatty acids—affects melting behavior, nutritional properties, and physical state of fats and oils. In metabolism, glycerol released from glycerides can be converted to glycerol-3-phosphate and enter carbohydrate metabolism, while fatty acids are channeled to energy production or, in storage tissues, remain tied up as triacylglycerols.