Agglomeration of a model food powder: Effect of maltodextrin and gum Arabic dispersions on flow behavior and compacted mass

The process of agglomeration of particulate foods was studied by employing corn starch as a model system. The effect of different liquid binders (maltodextrin and gum Arabic) to the extent of 1-5% was used to study the changes in the characteristics of the powder. Rheological behavior of powder was quantified in terms of textural indices like maximum force, and energy of compression and decompression. The physical and functional properties of powder and that of the pressure-compacted masses were determined to understand the behavior of the particulate foods in presence of binder liquid. The compacted masses were subjected to compression testing to obtain textural indices like strain at failure and Young's modulus. The different concentrations of gum and maltodextrin improved the wettability of powder. The electron micrographs were used to observe the characteristics of agglomerated particles including shape and size. The latter varied between 30 and 100 mu m for agglomerated masses compared to 12 mu m for untreated corn starch powder. (C) 2009 Elsevier Ltd. All rights reserved.