beta-Galactosidase immobilization for milk lactose hydrolysis: a simple experimental and modelling study of batch and continuous reactors.

The experiment described in this paper introduces students to the practical use of an enzyme (beta-galactosidase, or lactase) acting on a natural substrate. The enzyme is immobilized onto a cheap support, and the immobilized derivative is used in a packed-bed reactor for continuous milk lactose hydrolysis. The results are compared to those obtained for discontinuous batch reactors with soluble enzyme. A mathematical model of the two types of reactors is run, and its results are compared with the experimental data obtained.