Medium-chain triglycerides (MCTs) are triglycerides whose fatty acids have an aliphatic tail of 6–12 carbon atoms. The fatty acids found in MCTs are called medium-chain fatty acids (MCFAs).Like all triglycerides, MCTs are composed of a glycerol backbone and three fatty acids. In the case of MCTs, 2 or 3 of the fatty acid chains attached to glycerol are medium-chain in length.Rich sources for commercial extraction of beneficial MCTs include palm kernel oil and coconut oil.ike all triglycerides, MCTs are composed of a glycerol backbone and three fatty acids. In the case of MCTs, 2 or 3 of the fatty acid chains attached to glycerol are medium-chain in length.