Glycosides assembled from galactose plus an alcohol are galactosides, and hydrolysis splits them back into galactose and the alcohol partner. Lactose itself is the classic example, a galactoside of glucose that lactase cleaves during digestion. Plant galactosides include flavour and pigment precursors, and their enzymatic breakdown releases aroma or colour in foods. Analysts hydrolyse them to confirm identity, and processors use beta-galactosidases to dismantle them in lactose-free dairy production. The reaction also runs in reverse to synthesise prebiotic galactooligosaccharides for functional foods.