Fluidized bed granulation of gellan gum: Investigations of binder effect on physical, structural and rheological properties

Multiple binders such as maltodextrin, glucose and lactose at different concentrations were screened for the granulation of gellan gum (GG) in fluidized bed granulator to avoid limitations of powder GG such as dustiness, low dispersibility, wettability etc. Granulation was confirmed by analyzing physical, structural and rheological properties against commercial GG powder. Granulation significantly improved the particle size, flowability, dispersibility and wettability of GG without changing the native chemistry. Among the binders, lactose (10% w/ v) gave granules with highest particle size (D0.9 = 828 mu) and porosity (64%). The process retained the color and stability by decreasing water activity (aw < 0.30). However, binder type and concentration altered the flow and dynamic rheological properties of granular GG compared to non-granulated. Concisely, fluidized bed granulation seems to be a potential technique to improve processability of GG by overcoming existing limitations without altering the chemistry and functional properties at lower binder concentration.