The microparticulate carbohydrate is preferably water soluble, and subject to the foregoing proviso may for example be selected from hexoses such as glucose, fructose or galactose; disaccharides such as sucrose, lactose or maltose; pentoses such as arabinose, xylose or ribose; and polysaccharides such as ??-, ??- and ??-cyclodextrins, maltodextrin and glycogen; the term carbohydrate as used here