PRODUCTION OF CONCENTRATED FREEZE-DRIED CULTURES OF BIFIDOBACTERIUM-LONGUM IN KAPPA-CARRAGEENAN LOCUST BEAN GUM GEL

Bifidobacterium longum was immobilized in kappa-carrageenan/locust bea n gum gel beads, and cultured in a medium containing Lactobacillus MRS broth and whey-permeate. The same beads were incubated for 5 successi ve batch fermentations and freeze-dried following mixing with a protec tive solution. Viable population in the beads increased from 8 x 10(7) to 4.7 x 10(10) cfu/g after three batch fermentations, but no further increase in Viable cell population could be achieved in the last two fermentations. The freeze-dried culture contained 3 x 10(10) cfu/g wit h a survival rate of approximately 10%. Survival to freeze-drying of i mmobilized cells was as good as hat of classical free-cell cultures. S tability of freeze-dried cultures during storage at minus 17, 4 and 20 degrees C was not influenced by immobilization.