Comparative biochemical characterization of soluble and chitosan immobilized β-galactosidase from Kluyveromyces lactis NRRL Y1564

► Kluyveromyces strains were screened for β-galactosidase production on whey. ► Kluyveromyces lactis NRRL β-galactosidase Y1564 was immobilized onto chitosan. ► High operational stability of the immobilized enzyme was observed. ► High storage stability of the immobilized enzyme was observed for 93 days at 4 °C.