Abstract The enzymatic synthesis of flavour esters by trans‐esterification from vinyl esters and alcohols catalysed by free Candida antarctica lipase B (CaLB) in ionic liquids has been studied. The influence of different parameters, such us pH, temperature and ionic liquid nature, on activity and selectivity has been carefully analysed, using as reaction model the synthesis of butyl butanoate. Finally, a broad range of flavour esters were sucessfully synthesized using the optimal operation conditions previously established. Copyright © 2008 John Wiley & Sons, Ltd.