1. Introduction
The hydrolysis of starch to products with low molecular
weight, catalyzed by a-amylases is one of the most
important commercial enzyme processes. The hydrolyzed
products are widely applied in food, paper and textile
industries [1–4]. Industrial development of enzymic reactors
requires the use of immobilized enzymes in order to reduce
the cost of the biocatalyst. To a large extent this procedure
prevents enzyme losses due to washout and at the same time
maintains biocatalyst at high concentrations [5–7]. Effective
enzyme immobilization can be achieved using several
techniques, one of which is encapsulation within a gel
matrix. This immobilization technique consists of enclosing
the enzyme in an aqueous solution inside a semipermeable
membrane capsule. Basically, there are two main advantages
of this immobilization method, the particle structure allows
contact between the substrate and enzyme to be achieved
and in addition it is possible to immobilize several enzymes