ENZYMATIC ESTERIFICATION OF FATTY-ACID MIXTURES FROM MILK-FAT AND ANHYDROUS MILK-FAT WITH CANOLA OIL IN SUPERCRITICAL CARBON-DIOXIDE

The ester ethyl oleate was synthesized from oleic acid and ethanol by using the lipase, Candida cylindracea, immobilized on Celite 545 and in supercritical carbon dioxide (SC-CO2) as the solvent. The enzymatic esterification reaction is much faster in SC-CO2 than in organic solvents. This technique was then applied to the hydrolysis products of milk fat to determine the feasibility of using it as a process to enhance flavor. Gas chromatographic (GC) analysis of the ethyl esters showed that short-chain fatty acids (C4-C8) esterify more completely than long-chain fatty acids (C-16-C18). The technique was then applied to interesterify a mixture of triglycerides from canola oil (CNO) and anhydrous milk fat (AMF). The starting mixture contained predominantly C52-C56 triglycerides from the CNO and C32-C38 triglycerides from the AMF. The product exhibited predominantly the C42-C50 and C54 triglycerides.