The yield obtained in a Candida rugosa lipase-catalysed heptyl acetate synthesis via transesterification of 1-heptanol with vinyl acetate depends linearly on the concentration of lipases of each crude lyophilised powder. Thus, it is possible to characterise the amount of lipases present in the biocatalyst by calculating the parameter called Catalytic Performance (CP), defined as (% final yield) x (mg crude biocatalyst)(-1). On the other hand, the relative yield obtained in the C. rugosa lipase-catalysed transesterifications of different alcohols (1-heptanol. geraniol, nerol and cyclohexanol) with vinyl acetate as acyl donor depends on the proportion of isoenzymes of each crude biocatalyst. Therefore, it is possible to qualitatively evaluate the proportion of isoenzymes in those crude preparations and to predict the biocatalytical behaviour of each isoenzyme according to the alcohol employed. The methodology described is successfully used in two non-conventional asymmettic syntheses in organic media. (c) 2005 Elsevier Inc. All rights reserved.