Phenotypic and genotypic characterization of probiotic strain Bifidobacterium lactis BB-12 in baby cereal flakes enriched with inulin

Production of functional food containing probiotic bifidobacteria is increasing because of their beneficial effects on human health. The aim of this study was phenotypic and genotypic characterization of probiotic strain Bifidobacterium lactis BB-12 in wheat grits baby cereal flakes. Samples were prepared by adding lyophilised culture of Bifidobacterium lactis BB-12 to dehydrated wheat grits baby cereal flakes (with and without inulin). SDS-PAGE of whole cell proteins and RAPD-PCR were used for identification and characterization of this probiotic strain in baby cereal flakes. Samples were stored at 6 and 22 o C and were analyzed by plating on MRS agar in anaerobic conditions after 7 days, 14 days and 1, 2, 4, 8 and 12 month of storage. The initial number of probiotic strain Bifidobacterium lactis BB-12 has been 3.85 . 107 cfu/g of baby cereal flakes with Bifidobacterium lactis BB-12, and 4.45  107 cfu/g of baby cereal flakes with Bifidobacterium lactis BB-12 enriched with inulin. The survival of Bifidobacterium lactis BB-12 in baby cereal flakes was better when samples where stored at 6 o C and the number of viable probiotic bacteria was about 107 cfu/g after one year of storage. The viability of Bifidobacterium lactis BB-12 was reduced after one year storage at 22 o C by 3 and 2 log units with and without presence of inulin, respectively. The addition of inulin did not significantly influence the survival of probiotic strain Bifidobacterium lactis BB-12 during storage of baby cereal flakes at 6 o C.