We succeeded in the immobilization of 190 mg of periodate oxidized glucoamylase per gram of macroporous polymer. The covalently immobilized enzyme had a specific activity of 1100 U/g. The temperature and pH optimum as well as kinetic parameters were determined. The immobilized enzyme was tested in different types of reactors for hydrolysis of concentrated maltose and starch hydrolysate syrups. The DE value of 98.6, obtained the immobilized enzyme, was slightly higher than that for the soluble form, when acting on 20% substrates. During continuous use in a packed bed reactor over a period of 4 weeks the immobilized enzyme produced 1300 kg of glucose per 1 L of reactor volume without any decrease in its activity. (c) 2006 Elsevier Inc. All rights reserved.