Fermentation of banana media by using kappa-carrageenan immobilized Lactobacillus acidophilus

Fermentation media were prepared by using banana as the raw material, and cell immobilization of Lactobacillus acidophilus by kappa-carrageenan entrapment was applied to enhance the fermentation efficiency. Gel beads of diameters around 3.0 mm were prepared for the immobilized cells, ripe bananas were used for preparation of media, and both free and immobilized cells were employed to carry out the fermentation for 80 h. Cells leaked out from the gel beads and proliferated in the medium solution during the fermentation of immobilized cells. The final viable cell number reached 10(5) CFU/ml in the medium suspension, over 10(8) CFU/(ml gel) in gel beads for the immobilized cell fermentation and around 10(6) CFU/ml for the free cell fermentation. Immobilized cells withstand the adverse conditions in banana media resulting in better fermentation efficiency compared to free cells. Variation of fructooligosaccharides (FOS) in banana media was not significant in immobilized cell fermentation compared to free cell. Immobilized L. acidophilus fermented banana medium was found to possess synbiotic properties.