Milk powder was agglomerated in a small batch fluidized bed using pure water sprayed from a two-fluid nozzle. The influence on particle growth of liquid flowrate, mass of powder in the bed, initial particle size and product type (skim milk and whole milk) was studied.

The increase in particle size was found to be a homogeneously increasing function of the mass ratio of the sprayed water to the powder in the bed. There was no difference between the fat and non-fat products. The increase in particle size, measured as mass median diameter, was irrespective of the initial particle size.

Agglomeration was shown to improve wettability and flowability and to reduce bulk density.

Barkouti, A. et al., Dairy Sci. & Technol. (2013) 93:523-535