Production of microcapsules containing Bifidobacterium BB-12 by emulsification/internal gelation

- Internal ionic gelation provides protection of probiotic cells.
- Encapsulation protected microorganism in gastrointestinal stress tests.
- Encapsulation positively influenced the survival of the microorganism in storage.

Emulsification/internal gelation is an encapsulation technique with great potential for protection of probiotics for use in food products. In this study, microparticles containing Bifidobacterium BB-12 produced by emulsification using sodium alginate as wall material with a slow release of calcium ions were evaluated. Probiotics survival was studied for resistance to simulated gastrointestinal conditions and stability during 120 days of storage. The characterization of the microparticles and stability in buffer solutions at different pH (4.5, 6.0, and 7.5) was investigated. Although the free cells presented low resistance, the encapsulated bacteria were resistant to the simulated gastrointestinal conditions, providing protection to Bifidobacterium BB-12. A loss of viability was observed for the encapsulated microorganisms at 7 °C and 25 °C after 120 days, while the best viability was obtained at frozen storage (−18 °C), with a counts of 7.31 log CFU g−1 at the end of storage. The microparticles presented stability in buffer pH 4.5 and total release of probiotics at pH 7.5. The study indicates that the emulsification/internal gelation has proven to be a viable technology for protection, application, and controlled release of probiotics.