Effects of Fructooligofructoses Chain Length on the Bifidobacteria of the Human Colon: A Pilot Study

Abstract

Human gastrointestinal health may be improved by the consumption of prebiotic food ingredients such as fructooligo-fructoses. A study was initiated to determine the effect of fructooligofructoses of different chain lengths on gastrointes-tinal parameters. Nineteen healthy subjects aged 20 - 57 y took part in a 10-week cross-over designed study. Subjects consumed either inulin or oligofructose for 3 weeks followed by a 2-week washout period between treatments. Stool samples were collected five times (baseline, 2 treatments, 2 washout) and analyzed for bifidobacteria. Daily records were kept for stool frequency, stool consistency and flatulence frequency. Bifidobacteria counts (cfu/ml) were higher (trending toward significance) during inulin and oligofructose intakes (1.2 × 10 7 ± 4.8 × 10 7 and 2.0 × 10 8 ± 4.7 × 10 8 ) and washout periods (2.9 × 10 6 ± 6.5 × 10 6 and 1.1 × 10 7 ± 1.6 × 10 7 ) than baseline counts (2.2 × 10 5 ± 5.1 × 10 5 and 2.9 × 10 6 ± 6.5 × 10 6 ), respectively. Inulin and oligofructose treatment periods had a significant effect on stool consistency (watery/very hard) and flatulence frequency, but not stool frequency, when compared to baseline (P < 0.05). Further research is needed to confirm these results due to small sample size and the need for a longer washout period between treatments.