Different immobilized lipases were screened for their ability to esterify free fatty acids (FFA) with monoacylglycerol (MAG) as acyl-group acceptor. A lipase from Rhizomucor miehei (Lipozyme RMIM) was the most suitable for lipase-catalyzed de-acidification-a promising alternative to conventional neutralization. A reduction of the FFA content to 0.6 % (w/w) was achieved by applying a substrate with an initial FFA-content of 6 % (w/w), the reaction at 50 °C for 22 h as well as the stepwise addition of a quadruple stoichiometric amount of MAG.