Optimization of microencapsulation of probiotics in raspberry juice by spray drying

Probiotics were microencapsulated in raspberry juice through spray drying. A combination of probiotics (Lactobacillus acidophilus NRRL B-4495 and Lactobacillus rhamnosus NRRL B-442) was chosen to offer high viability. Maltodextrin's role as a carbon source was also assessed for its prebiotic potential. Spray drying inlet temperature (°C), total solids: maltodextrin ratio, and inlet feed rate (mL/min) were fixed as independent variables while % recovery, % survival and color were the dependent outputs. High temperatures during spray drying are detrimental to probiotics and can be circumvented by sub-lethal thermal shock (50 °C for L. acidophilus and 52.5 °C for L. rhamnosus). Increasing the microencapsulating material concentration increased the survival rate of the probiotics. Non-dairy probiotic foods are becoming popular as they do not pose problems of lactose intolerance while they offer an alternative.