Acidolysis of Sunflower Oil with Rhizomucor miehei Lipases Immobilized on Modified Chitosan Microspheres

CAMILA A. PALLA; CONSUELO PACHECO; MARÍA E. CARRÍN

Buenos Aires

Congreso; XIII Congreso Argentino de Ciencia y Tecnología de Alimentos; 2011

Enzymatic lipid modification is of current interest to scientists and industrials, particularly to obtain trans-free fats and oils. An extra advantage is obtained when immobilized enzymes are used. Nowadays different lipases are commercially available immobilized on different supports but economical or operational problems could happen with them. The aim of this work was to obtain a proper biocatalyst, cheaper and difficult to be broken, in order to use it, in the future, into a fix-bed reactor. Chitosan microspheres were prepared for using as immobilization support. The hydrophilic nature of them was modified to a more hydrophobic one by reductive amination, and lipases from Rhizomucor miehei were adsorbed onto them by physical adsorption. Different variables in the immobilization protocol were analyzed: an initial soak of the support with ethanol or phosphate buffer and the addition or not of chilled acetone at the end of the process. The catalytic behavior of the obtained enzyme derivatives was evaluated in the acidolysis of sunflower oil with a mixture of palmitic—stearic acids at standardized conditions. The best results were obtained when the immobilization was performed using buffer media alone, achieving palmitic and stearic acid incorporations of 274.4 % and 320.7 %, respectively.