The Flow Properties of Starch Powders and Mixtures

The addition of small proportions of fine powders, particularly magnesium oxide, to maize starch, alters its flow properties in a manner which is contrary to the generally observed effects for fine powders. A measure of this effect is obtained by the angle of repose method and the disposition of the two components of the mixture is observed by the electron microscope. An explanation of this effect in terms of adhesion by Van der Waals' and valency forces is put forward.