Growth and metabolism of selected strains of probiotic bacteria in milk- and water-based cereal puddings

Abstract

Abstract The growth and metabolism of four probiotic strains ( Lactobacillus acidophilus La5 and 1748, Bifidobacterium animalis Bb12, and Lactobacillus rhamnosus GG) were studied in milk- and water-based puddings containing both maize and rice flour. All pudding-formulations were produced both with and without the potential prebiotic polydextrose, Litesse™, to see if this addition had any effect on the growth, metabolism and survival of the probiotic strains. Puddings were analysed for viable cell count, pH and metabolites during fermentation (12 h, 37°C) and after refrigerated storage (21 d, 4–6°C). All strains showed good growth and survival in milk-based puddings (8–9.1 log cfu g −1 ), but L. rhamnosus GG was the only strain with an acceptable survival in water-based puddings (8 log cfu g −1 ). After storage, 560–9800 mg kg −1 lactic acid was produced, with significantly higher concentrations in milk-based puddings ( p L. rhamnosus GG, reaching 18 mg kg −1 in milk-based puddings. In most cases, puddings prepared with or without the addition of Litesse™ were not significantly different.