The emulsification/internal gelation is an innovative technique for production of microparticles ionic polysaccharide. Emulsification is more feasible in particle size control and large-scale production. The aim of this study was the development of microparticles with Bifidobacterium BB-12 by emulsification/internal gelation and evaluation of these microparticles in different buffers. For the preparation of emulsions it was used a solution of 1.5% sodium alginate and it was mixed with the freeze-dried microorganism. This mixture was dispersed in oil containing a concentration of 1.5% Tween 80 with a rotation speed of 900 rpm using a stirrer. After the complete separation of microparticles, the oil was discarded and the capsules were filtered through sieves, washed and stored at 4 ° C. The behavior of the microcapsules was evaluated in buffer solutions with pH 4.5, 6.0 and 7.5. The solutions were submitted to shaking, and aliquots removed after 60, 120 and 180 minutes each. The microorganisms were enumerated on MRS agar supplemented by seeding depth and incubation at 37 °C in anaerobiosis for 72 hours. The results were submitted to statistical analysis (ANOVA and Tukey test).It was obtained counts logarithmic cycles of 12 cells per gram of bacteria after emulsification. It was found that a controlled release profile as a function of pH due to the retention of cells in solutions of pH 4.5 and complete release of the cells in solutions with pH 7.5 after 3 hours of reaction. This release profile shows that these particles have potential for application in food with a pH below 4.5, and to a possible controlled release in the intestine. Completing the emulsification process may be used to produce alginate microspheres for encapsulation of Bifidobacterium BB-12 resulting in particles with controlled release depending on pH.