Two grams of freshly spray-dried orange juice powders were spread on a Petri dish and were put in each desiccator. The lid of the desiccators were double sealed using three layers of a thin polythene film to ensure a sealed environment in the desiccators. The samples were taken out of the desiccators every two days to measure their weight using a four-figure (±0.0001 g) analytical balance (Mettler Toledo AB204-S, Switzerland) until the mass change of the sample was less than 0.001 g. After a constant weight was observed, the equilibrium moisture content of the samples was determined by oven drying at 85 C for 24 h using a fan-forced drying oven and was reported on a dry basis (Thermoline TD150F). The whole procedure was repeated three times for each temperature.