Finally, the conditions under which maltodextrin lumps may form were revealed. Lumps observed for maltodextrin DE21, DE6, and IT6 tended to float just below the liquid surface, despite the fact that the true density of the material is greater than that of water (Table 1); this is an indication that the lumps contained entrapped air inside. The proposed mechanism for their formation is the development of a viscous gel-like layer around dry particles that is impermeable to water. The air entrapped along with the dry particles thus cannot be displaced by water, creating a greater buoyant force that lifts lumps towards the liquid surface.