1,2,3-Triacetylglycerol (I) and 1,2,3-trioctanoylglycerol (II) were (iso)propanolyzed at 50degreesC over 7% (triglyceride basis) of a lipase (from Candida antarctica) immobilized on a porous acrylic resin, H2O 2-3%, at 1- or 2-PrOH-to-acid residue (in triglyceride) ratios of 1:1, 2:1, 3:1, 5:1 and 10:1. II reacted much faster than did L Long-time reactions showed enzymatic decomposition of tri to monoglycerides to be irreversible (no tri, no diglycerides). The lipase was 1,3-specific and short-time reactions produced no glycerol. Intermediate products of 1- and 2-propanolysis of the triglycerides differed in yield.