A study of solid-state epimerisation within lactose powders and implications for milk derived ingredients stored in simulated tropical environmental zones.

Isolated from milk, lactose is a food ingredient and an excipient in medicines. Its chiral forms are known to undergo epimerisation in solution but understanding whether this chemical reaction occurs in lactose powders exposed to tropical environments is of great importance for medicine stability and food quality. Thus, the aim of this study was to investigate epimerisation within lactose powders stored under specified conditions that model hot and humid climates.

Stability of α-lactose monohydrate: The discovery of dehydration triggered solid-state epimerization.

Lactose is present as an excipient in nearly half of all solid medicines. Despite the assumption of chemical stability, in aqueous solution, the chiral composition of lactose is prone to change. It is not known whether such epimerisation could also occur as solid crystalline α-lactose undergoes thermal desorption of its hydrated water.