Abstract
Refined olive oil was enriched with palmitic acid (PA) and docosahexaenoic acid (DHA) via lipase-catalyzed acidolysis reaction using Novozym 435 in hexane. The enrichment reaction was optimized by response surface methodology. Three independent variables, reaction time (12, 18, and 24 h), temperature (55, 60, and 65 °C), and substrate molar ratio (refined olive oil:DHA single cell oil free fatty acid:PA 1:1:6, 1:1:9, and 1:1:12) and three responses, total PA and DHA incorporation, and PA content at the
sn
-2 position were investigated. Results showed that PA was incorporated into the triacylglycerols(TAGs) of refined olive oil at up to 55.79 mol % while incorporation of PA at the
sn
-2 position and total DHA were found to be up to 33.63 and 3.54 mol %, respectively. Second-order models were generated for each of the three responses. A Chi-square test verified that the predicted values from the models were not significantly different from the observed ones. The prediction power of the models was further confirmed by a solvent-free scale-up reaction. The produced structured lipids have the potential to be used in infant formula.