Lactitol (CAS NO.: 585-86-4), with its other name of 4-O-beta-D-Galactopyranosyl-D-glucitol, could be produced through many synthetic methods.

Following is one of the synthesis routes: Lactitol is obtained by catalytic hydrogenation of lactose (I) in the presence of either, nickel catalysts such as Raney nickel (1-9), or ruthenium catalysts (10). Alternatively, lactose (I) is reduced by employing NaBH₄ (9).