Lactose : polymorphism, caking behaviour and use in pharmaceuticals

Lactose is an important ingredient used by the pharmaceutical industry, which is one of the largest consumers of the highly purified grades of this saccharide. Although the usual commercial product is crystalline a-lactose monohydrate, many users are unaware that lactose exists in numerous polymorphic and isomeric forms, each form possessing a range of unique particle characteristics such as flowability, compactibility, hygroscopicity, solubility, and shelf life (e.g. tendency to cake). Not all of these characteristics have been fully exploited by the pharmaceutical industry. This paper reports on work directed to better understanding how the characteristics of lactose particles affect their functional qualities