Question: what is the difference between alpha and beta lactose?
Answer: Lactose has two anomers (stereo-isomers), α and β, differing only in the configuration of the hydroxyl group at the anomeric hemiacetal carbon. α has an axial hydroxyl whereas β hydroxyl is equatorial (Figure 1). 1-3 The β-isomer is obtained by crystallization above 93.5° C as a non-hygroscopic anhydrous form.