Effect of operational parameters of spouted bed dryer on the physical properties of milk powder

In this study, the effect of the inlet air temperature and milk flow rate on the physical properties of the milk powder obtained from the spouted bed dryer was investigated. Milk samples were dried at three levels of inlet air temperature (80, 100 and 120 ○C) and three levels of milk flow rate (1.333, 2.500, 3.556 ml/min). The effect of these factors on the physical properties (bulk density, tapped density, flowability, color, and moisture content) of the powders was evaluated. The effects of the mentioned factors on the physical properties of milk powder were determined and modeled using response surface methodology. The optimum inlet air temperature and the milk flow rate was obtained 93.82 ○C and 1.333 ml/min, respectively. Under these conditions, the desired values for each physical parameter were predicted and compared with the experimental data.