Highly stable novel silica/chitosan support for β-galactosidase immobilization for application in dairy technology

•Silica/chitosan biocatalyst for application in dairy technology.•Novel silica/chitosan composite support for β-galactosidase immobilization.•Morphological and textural characterization of silica/chitosan composite materials.•Application of the biocatalysts in lactose hydrolysis reaction in continuous operation system.•Biocatalyst with high activity for continuous use, showing mechanical stability.