Microencapsulation of a probiotic bacteria with alginate–gelatin and its properties

Abstract

Lactobacillus casei ATCC 393-loaded microcapsules based on alginate and gelatin had been prepared by extrusion method and the product could increase the cell numbers of L. casei ATCC 393 to be 10⁷ CFU g⁻¹ in the dry state of microcapsules. The microparticles homogeneously distributed with size of 1.1 ± 0.2 mm. Four kinds of microcapsules (S₁, S₂, S₃ and S₄) exhibited swelling in simulated gastric fluid (SGF) while the beads eroded and disintegrated rapidly in simulated intestinal fluid (SIF). Cells of L. casei ATCC 393 could be continuously released from the microcapsules during simulated gastrointestinal tract (GIT) and the release amounts and speeds in SIF were much higher and faster than that in SGF. Encapsulation in alginate–gelatin microcapsules successfully improved the survival of L. casei ATCC 393 and this approach might be useful in delivery of probiotic cultures as a functional food.

Key words: :

• Microcapsule
• lactobacillus casei ATCC 393
• relative humidity (RH)
• stability
• release

Acknowledgements

The authors are indebted to the financial support from NSFC (No. 30770582) and the ISTCP (No. 2006DFA33150).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.