β-galactosidase, commonly named lactase, is one of the most important enzymes used in dairy processing. This enzyme can be produced by different microorganisms, mainly from yeasts such as Kluyveromyces lactis, K. fragilis, K. marxianus, and from fungi like Aspergillus oryzae and A. niger. This enzyme catalyzes the hydrolysis of lactose to its constituent monosaccharides – glucose and galactose. Production of low lactose milk and whey is enabled by this process allowing intake of such dairy product to the people affected by lactase insufficiency. Besides, it is possible to use β-galactosidase for obtaining galacto-oligosaccharides known as very important prebiotic additives for food industry. This article reviews the possibility of β-galactosidase immobilization by different techniques as well as its application as biocatalysts in food industry, especially in dairy processing.
