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

Abstract

Oligosaccharides, the 3rd 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