Milk fermented with yogurt cultures and Lactobacillus casei compared with yogurt and gelled milk: influence on intestinal microflora in healthy infants

Am J Clin Nutr. 1998 Jan;67(1):111-7. doi: 10.1093/ajcn/67.1.111.


Ingestion of fermented dairy products induces changes in the equilibrium and metabolism of the intestinal microflora and may thus exert a healthful influence on the host. We compared the effects of consumption of a traditional yogurt, a milk fermented with yogurt cultures and Lactobacillus casei (YC), and a nonfermented gelled milk on the fecal microflora of healthy infants. Thirty-nine infants aged 10-18 mo were randomly assigned to one of three groups in which they received 125 g/d of one of the three products for 1 mo. The following indexes were not modified during the supplementation period or for 1 wk after the end of supplementation: total number of anaerobes, bifidobacteria, bacteroides, and enterobacteria; pH; water content; concentrations of acetate, butyrate, propionate, and lactate; and bacterial enzyme activity of beta-galactosidase and alpha-glucosidase. In contrast, in the yogurt group the number of enterococci in fecal samples increased (P < 0.05), whereas the percentage of branched-chain and long-chain fatty acids, which are markers of proteolytic fermentation, decreased (P < 0.05). In the YC group, the percentage of children with > 6 log10 colony-forming units lactobacilli/g feces increased (P < 0.05), whereas the potentially harmful enzyme activity of beta-glucuronidase and beta-glucosidase decreased (P < 0.05). These decreases were particularly marked in those infants in the YC group in whom activity of the enzymes was initially unusually high.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / growth & development
  • Cohort Studies
  • Colony Count, Microbial
  • Dairy Products / microbiology*
  • Feces / chemistry
  • Feces / enzymology
  • Feces / microbiology
  • Fermentation
  • Follow-Up Studies
  • Food Microbiology*
  • Humans
  • Hydrogen-Ion Concentration
  • Infant
  • Infant Food / microbiology*
  • Infant Food / standards
  • Infant Nutritional Physiological Phenomena / physiology*
  • Intestinal Mucosa / metabolism
  • Intestines / enzymology
  • Intestines / microbiology*
  • Lactobacillus casei / metabolism
  • Milk / metabolism
  • Milk / microbiology
  • Time Factors
  • Water / analysis
  • Yogurt / microbiology


  • Water