This study focussed on the use of high voltage electrostatic fields to spray solutions of the nonspecific lipase Candida rugosa into high oleate sunflower oil and to determine rates of hydrolysis. Significant increases in reaction rate are reported. The kinetics were analysed using a modified reaction model for enzymatic reactions at free liquid interfaces. Similar data for hydrolysis rate within dispersions formed by mechanical agitation in a recycle reactor were similarly measured and interpreted. In both cases good agreement was obtained between the experimental measurements and the predicted results. (C) 2003 Society of Chemical Industry.