Kluyveromyces lactis β-galactosidase immobilized on collagen: catalytic stability on batch and packed-bed reactor hydrolysis

The aim of this study was to evaluate the catalytic characteristics and operational stability of the tetrameric Kluyveromyces lactis β-galactosidase (KLG) enzyme immobilized on collagen. The support was submitted to four different treatments: aluminum, glutaraldehyde, acetic acid, and a combination of the methods with aluminum and glutaraldehyde. The four modified supports and the enzyme, both in its soluble and immobilized forms, were studied using thermogravimetric, differential exploratory calorimetry, infrared spectroscopy, and textural analyses. Operational pH, temperature and kinetic parameters of the soluble enzyme and of derivatives were characterized. Immobilized enzyme was applied in milk and whey lactose hydrolysis, via batch and continuous processing. There was no significant reduction ( p