Mono- and Diglycerides of Fatty Acids are manufactured either by glycerolysis of hydrogenated edible oils or by direct esterification of glycerol with food-grade fatty acids (typically stearic or palmitic).
This yields a mixture of mono-, di- and tri-glycerides with 40-55% monoglyceride content. They are the most versatile and widely used emulsifier in the food industry.