Type of fat derived from glycerol and two fatty acids
General chemical structures of 1,2-diacylglycerols (top) and 1,3-diacylglycerols (bottom), where R1 and R2 are fatty acid side chains
A diglyceride, or diacylglycerol (DAG), is a glyceride consisting of two fatty acid chains covalently bonded to a glycerol molecule through ester linkages.[1] Two possible forms exist, 1,2-diacylglycerols and 1,3-diacylglycerols. Diglycerides are natural components of food fats, though minor in comparison to triglycerides.[2] DAGs can act as surfactants and are commonly used as emulsifiers in processed foods. DAG-enriched oil (particularly 1,3-DAG) has been investigated extensively as a fat substitute due to its ability to suppress the accumulation of body fat;[3][4] with total annual sales of approximately USD 200 million in Japan since its introduction in the late 1990s till 2009.[3]