15E-22 |
Lipase-catalyzed acidolysis of olive oil and conjugated linoleic acid in a microaqueous system |
J. C. Vinay1, C. E. Martinez1, C. G. Hill, Jr.2, and H. S. GARCIA1. (1) UNIDA, Instituto Tecnologico de Veracruz, M.A. de Quevedo # 2779, Col. Formando Hogar, Veracruz, Ver., 91897, Mexico, (2) Dept. of Chemical Engineering, University of Wisconsin-Madison, 1415 Engineering Dr., Madison, WI 53706 Conjugated linoleic acid (CLA) refers to a mixture of positional and geometric isomers of linoleic acid. This family of isomers has been studied for the past several years due to its nutraceutical properties. Interesterificaction of chemically-produced CLA may be a practical way for incorporation into edible fats and oils. The objective of this work was to prepare olive oil glycerides containing high concentrations of CLA by acidolysis in a water-restricted environment. Reaction conditions involved a batch reactor at temperatures of 45,55,65 and 75 °C, enzymes from Rizomucor miehei and Candida antarctica were used. CLA to olive oil ratios (w/w) of 1:9, 1:7, 1:5, 1:3, 1:1 and enzyme/substrate rates of 5, 8 and 11%, at moisture contents of 0.05, 0.6, 1.0, 2.0 and 4.0% were employed. A kinetic model for acidolysis previously derived was used to fit the data. Results suggest that the enzyme from R. miehei was able to achieve greater CLA residues esterified at 55 °C, a CLA:oil ratio of 1:1, and 5 % enzyme concentration. The non-specific lipase from C. antarctica reached highest acidolysis yield at 75 °C and 11 % enzyme concentration at the same conditions as for the former. Acidolysis reactions proceeded fast during the first hours with the enzyme from R. miehei performing better than that from C. antarctica. Water content affected both reaction rate and the presence of free fatty acids as well as mono- and diacylglycerides. Commercial enzyme preparations can be used to implement production of CLA-rich oils
Session 15E, Nutraceuticals & Functional Foods I
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