Optimization of immobilization process on crab shell chitosan and its application in food processing

Abstract

Optimization of immobilization process on crab shell chitosan was carried out. The chitosan purified from the crab shell was used as the matrix for the immobilization of ?-galactosidase. The prepared matrix was activated with glutaraldehyde at different concentrations and different time intervals and coupling time was determined. Immobilization of ?-galactosidase on crab shell chitosan resulted in 72% immobilization yield. The parameters like the effect of pH, temperature, thermal stability and storage stability were determined. The study revealed that immobilized enzyme shows better thermal and storage stability than the free enzyme. The performance of the free and immobilized ?-galactosidase was tested in continuous stirred batch reactor to hydrolyze raffinose family oligosaccharides in soymilk. The oligosaccharide content of the soymilk was reduced by 77% in continuous reaction by immobilized ?-galactosidase. © 2008, Wiley Periodicals, Inc.