Characterization of sugar caking during silo storage using penetrometric tests

The caking of sucrose crystals during storage was investigated experimentally by using a laboratory silo, 0.6 L in volume. The extent of caking in the bulk of sugar was quantified from penetrometric tests. The extent of caking depends on various operating parameters, such as the flow-rate of inlet air, its humidity, as well as the temperature during the drying operation, prior to storage. It was noticed that a sudden decrease in the humidity of inlet air results in the phenomenon of caking. Nevertheless, this phenomenon is not irreversible, because sugar can be “uncaked” by introducing into the silo some humid air or steam from pure water.