Soaps are formed from the reaction of glycerides with sodium hydroxide. The product of the reaction is glycerol and salts of fatty acids. Fatty acids in the soap emulsify the oils in dirt, enabling the removal of oily dirt with water.
Partial glycerides are esters of glycerol with fatty acids, where not all the hydroxyl groups are esterified. Since some of its hydroxyl groups are free the molecule is polar. Short chain partial glycerides are more highly polarized, and have excellent solvent properties for many hard-to-solubilize drugs.