Abstract:The effects of different processing parameters on the quality of powdered total-nutrition food for special medical purposes (FSMP) during the spray drying process were investigated to obtain the optimal preparation process for the spray-dried powder of total-nutrition FSMP. Using vitamin C (Vc) and oil encapsulation rates as evaluation indexes for powder quality, the spray drying processing parameters were optimized based on the Box-Behnken central composite method. The effects of spray drying parameters, such as inlet air temperature, injection speed, injection concentration, and air velocity, on the quality of powdered total-nutrition FSMP were investigated to determine the optimal spray drying process conditions. The storage stability of total-nutrition FSMP prepared by spray drying under different accelerated test conditions (high temperature, high humidity, and bag opening) were studied using the conventional dry mixing method as the control. The results showed that the optimal process conditions for wet spray drying of total-nutrition FSMP were injection concentration at 24%, inlet temperature of 132 ℃, injection speed of 13.5 mL/min, and air velocity of 30 Hz. The Vc and oil encapsulation rates of total-nutrition FSMP prepared using this process were 79.72% and 92.25%, respectively, and the blend uniformity was up to 99.68%. The results of accelerated testing demonstrated that compared to conventional dry mixing, this technique could effectively slow down lipid oxidation and the loss of Vc content, while also improving the storage stability of the powder. Therefore, our findings can provide technical support for improving the quality of powdered total-nutrition FSMP.
