1 Research Article A Method of Early-Phase Selection of Carrier for Aspergillus Oryzae β-Galactosidase Immobilization for Galactooligosaccharides Production † Jana Adamíková Monika Antošová Milan Polakovič Department of Chemical and Biochemical Engineering, Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovakia Correspondence: Professor Milan Polakovič Department of Chemical and Biochemical Engineering, Institute of Chemical and Environmental Engineering, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovakia. E-mail: milan.polakovic@stuba.sk Keywords: β-galactosidase; biocatalyst; galactooligosaccharides; immobilization; transglycosylation Abbreviations: GOS, galactooligosaccharides; ONPG, ortho-nitrophenyl-β-galactoside † This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: [10.1002/biot.201800120]. This article is protected by copyright. All rights reserved Received: February 25, 2018 / Revised: April 13, 2018 / Accepted: May 2, 2018