Development, characterization and viability study of probiotic microcapsules produced by complex coacervation followed by freeze-drying

Technique of complex coacervation was used to produce microcapsules of Lactobacillus acidophilus La-5 encapsulated in gelatin and gum arabic which were then freeze-drying. Microcapsules were characterized using scanning electron and optical microscopy, and resistance of probiotics was evaluated during release into a simulated gastrointestinal tract and storage at different temperatures. The complex coacervation process produced microcapsules with a high encapsulation efficiency (77.60% and 87.53%), ranging from 127.14-227.05 mu m with uniform distribution. Microencapsulation was an efficient approach to achieve significant protection of probiotics against simulated gastrointestinal conditions compared with free cells. Encapsulation also improved the viability of probiotics during storage at either -18 degrees C for 120 days, 7 degrees C for 105 days or 25 degrees C for 45 days. Therefore, complex coacervation was demonstrated to be adequate and promising for encapsulation of probiotics.