Optimization of microencapsulation of probiotics in raspberry juice by spray drying

AimsProbiotics were microencapsulated in raspberry juice through spray drying.Methods & ResultsA 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.Conclusions & SignificanceHigh 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.

► Probiotic foods require a viability > 106-108 CFU/unit at consumption time. ► A non-dairy raspberry probiotic powder was developed. ► Sub lethal treatment before spray drying protected the probiotics during drying. ► Optimization of spray drying was performed with an overall desirability of 0.91.