Polydextrose enrichment of infant formula acts as a prebiotic by increasing ileal lactobacilli and lactic acid concentration and decreasing pH

Oligosaccharides, the 3 rd largest component in human milk, are virtually absent from cow's milk and most infant formula. Polydextrose (PDX) is a proposed substitute for human milk oligosaccharides. One‐day old pigs were fed a cow‐milk‐based formula supplemented with PDX (0, 1.7, 4.3, 8.5 or 17 g/L) for 18 days (n=13). Additional reference groups included 12 pigs sampled at day 0 and 12 sow‐reared pigs sampled at day 18. Ileal lactobacillus CFU, but not bifidobacteria, increased linearly with increasing PDX (P = 0.02). Short chain fatty acids did not differ among treatments, but lactic acid increased linearly with PDX (P = 0.001). Lactic acid increased ten‐fold over control pigs in those supplemented with 8.5 and 17 g/L PDX. Accordingly, digesta pH decreased linearly (P < 0.05) as PDX increased, with a maximal reduction approaching 0.5 pH units in those fed 17 g/L. Ileal villus height, crypt depth, maltase, myeloperoxidase and the number of intraepithelial lymphocytes were not affected by dietary PDX (P > 0.1). Polydextrose enrichment of infant formula acted as a prebiotic by increasing lactic acid production and decreasing pH. Research supported by Mead Johnson Nutrition. Grant Funding Source: Mead Johnson Nutrition