The reaction model of producing 1,3-dioleic-2-palmitate (OPO) from substrates of tripalmitate (PPP) and oil-tea camellia seed oil free fatty acid (FFA) catalyzed by Lipozyme RM IM was used to investigate the influence of solvent (acetone, tert-butanol, n-hexane), reaction time (0, 2, 4, 6, 8 h) and water activity (aw)(0.11, 0.53, 0.97) on acyl migration. The results showed that among the three solvents, acetone promoted the incorporation of oleic acid and limited acyl migration. While the highest contents of oleic acid in sn-1,3 position and palmitic acid in sn-2 position were observed when water activity was 0.53 no matter in different solvents, meaning that the water activity was the dominant factor influencing the selectivity of Lipozyme RM IM. From the view of the green, environment and safety, the non-solvent system could be used but the water activity should be carefully controlled to inhibit acyl migration. |