Microbial technologies in the production of low-lactose dairy foods

Low-lactose milk products with 70% or more of the lactose hydrolysed by food grade p-galactosidase enzymes of yeasts or fungi have become widely accepted for alleviating the symptoms of lactose maldigestion. This condition limits the intake of nutritious dairy foods by large segments of the world's population. Alternative approaches recently proposed for dealing with lactose maldigestion include the supplementation of milk with dormant dairy cultures, treatment of milk with sonicated or permeabilized cultures as food-grade sources of beta-galactosidase and the use of cold-active enzymes to hydrolyse lactose in milk under refrigerated storage conditions.