33G-11 |
|
C. E. MARTÍNEZ-SÁNCHEZ1, E. Herman-Lara1, H. S. Garcia2, B. Hernandez- Santos1, and J. Hernandez-Iturbide1. (1) Biochemical Engineering Dept., Instituto Tecnologico de Tuxtepec, Calz. Dr Victor Bravo Ahuja s/n, Col. 5 de Mayo, Tuxtepec, Oax., 68360, Mexico, (2) UNIDA, Instituto Tecnologico de Veracruz, M.A. de Quevedo # 2779, Col. Formando Hogar, Veracruz, Ver., 91897, Mexico Conjugated linoleic acid (CLA) is a term used for 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. Interesterification of chemically produced CLA may be a practical way for incorporation into edible fats and oils. The objective of this work was to prepare corn oil glycerides containing high concentration of CLA by acidolysis in a water restricted environment. Reaction conditions involved a batch reactor at temperatures of 50, 60 and 70 Celcius degree; enzymes from Rhizomucor miehei and Candida antarctica were used. CLA to corn oil ratio (w/w) of 1:7, 1:5, 1:1 and enzyme/substrate rates of 5, and 11 %, at moisture contents of 0.05, 1.0 and 2.0% were employed. A kinetic model for acidolysis previously derived was used to fit the data. Results suggested that enzyme from R. miehei was able to achieve greater CLA residues esterified at 50 Celcius degree, CLA: oil ratio of 1:1 and 5 % enzyme concentration. The non-especific lipase from C. antarctica reached highest acidolysis yield at 70 Celcius degree 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. meihei 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 employed to prepare edible oils rich in CLA residues via acidolysis reactions.
Session 33G, Nutraceuticals & Functional Foods: Lipid and probiotic functional foods
|