a deleterious effect on product color and quantity the reactants are provided to a suitable vessel and heated to a temperature of from about 110 to about 130 u00b0 c preferably under a vacuum to melt the reactants and to remove any volatile material present then the contents of the vessel are heated to a temperature of from about 165 to about 255 u00b0 c preferably from about 190 to about 250 u00b0 c more preferably from about 190 to about 230 u00b0 c the reaction is preferably conducted under vacuum conditions to facilitate the removal of water which drives the reaction to completion when the level of free fatty acid content falls to less than about 10 weight percent preferably less than about 6 weight percent the temperature of the reaction is increased to about 230 to about 240 u00b0 c at this time the level of foaming in the vessel has also dropped which is another indication that it is appropriate to raise the temperature of the vessel after the desired free fatty acid level is achieved it is preferable to initiate a steam sparge the steam sparge is an effective technique to remove excess or unreacted fatty acids from the reactor the reaction is complete when the fatty acid content falls below 1 weight percent preferably less than about 0 5 weight percent and more preferably less than about 0 2 weight percent one of the most effective aspects of the present invention is that the reaction is preferably performed neat wherein no solvents are added to the reaction mixture because the acid particularly fatty acids acts as both a reactant and solvent in addition.