Lipase-Catalyzed Acidolysis of Palm Mid Fraction Oil with Palmitic and Stearic Fatty Acid Mixture for Production of Cocoa Butter Equivalent

Abstract

Cocoa butter equivalent (CBE) was prepared by enzymatic acidolysis reaction of substrate consisting of refined palm mid fraction oil and palmitic-stearic fatty acid mixture. The reactions were performed in a batch reactor at a temperature of 60 °C in an orbital shaker operated at 160 RPM. Different mass ratios of substrates were explored, and the composition of the five major triacylglycerols (TAGs) of the structured lipids was identified and quantified using cocoa butter certified reference material IRMM-801. The reaction resulted in production of cocoa butter equivalent with the TAGs' composition (1,3-dipalmitoyl-2-oleoyl-glycerol 30.7%, 1-palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol 40.1%, 1-palmitoy-2,3- dioleoyl glycerol 9.0%, 1,3-distearoyl-2-oleoyl-glycerol 14.5 %, and 1-stearoyl-2,3-dioleoyl glycerol 5.7%) and with onset melting temperature of 31.6 °C and peak temperature of 40.4 °C which are close to those of cocoa butter. The proposed kinetics model for the acidolysis reaction presented the experimental data very well. The results of this research showed that palm mid fraction oil TAGs could be restructured to produce value added product such as CBE.