Microencapsulation of probiotics in multi-polysaccharide microcapsules by electro-hydrodynamic atomization and incorporation into ice-cream formulation

Abstract Ca-alginate/chitosan microcapsules were made by electro-hydrodynamic processing. Two different microstructures were formed through the application of single- or double-stage procedures. Inulin or resistant starch, as prebiotic components, and Lactobacillus plantarum, as a probiotic strain, were incorporated into the microcapsules and viability of bacteria was monitored during the storage for 90 days. Microcapsules containing probiotic-prebiotic blends were employed as an ingredient in the formulation of ice-cream. The bacterial survival was also studied after the production and storage of the ice-cream. FTIR spectra confirmed the formation of polyelectrolyte complexes between alginate and chitosan. SEM images revealed that a chitosan layer thoroughly coated the Ca-alginate microcapsules formed through the double-stage procedure. After incorporation of either inulin or resistant starch into the microcapsules, the signal of the inulin was detected at 935 cm−1, and signals of the starch were traced at 1157 and 930 cm−1 in their FTIR spectra. Both polysaccharide matrices significantly improved probiotic survival during the storage of microcapsules. However, inulin-containing microcapsules showed a better performance than starch-containing ones as 7.23 ± 0.21 and 9.15 ± 0.33 log CFU g−1 of probiotics remained viable in them after storage at 25 and 4 °C, respectively. The microcapsules also improved the viability of probiotics after incorporating into the ice-cream as 7.37 ± 0.12 and 7.82 ± 0.39 log CFU g−1 of bacteria were viable after 90 days in inulin- and starch-containing microcapsules, respectively. These findings suggest that such microcapsules could be used as an ingredient for formulated functional foods.