Optimization of spray-drying process for the microencapsulation of (MCC 2974) in ultrasound hydrated finger millet milk.

Spray drying process was optimized for the development of probiotic finger millet milk powder. The independent parameters considered were inlet air temperature, maltodextrin content, and feed rate depending upon the preliminary trials. The major dependent quality parameters considered in the current work were moisture content, water activity, powder yield, encapsulation efficiency, and viability reduction. The desirability function was considered as a basis for the optimization of spray drying process. At the optimum process conditions of 151.68 °C of inlet air temperature, 100 mL/h of feed rate, and 29.32% of maltodextrin content, probiotic finger millet milk powder with 43.81% of powder yield and 84.97% of higher encapsulation efficiency could be achieved. The SEM analysis of the spray-dried powder confirmed the proper encapsulation of viable cells in the powder matrix. XRD analysis showed the amorphous powder structure suitable for other food applications. The promising results could be further utilized to produce non-dairy probiotic finger millet milk powder.