On the presence of Inulin and Oligofructose as natural ingredients in the western diet

Abstract

The classic definitions of inulin and oligofructose are constructively criticized. It is observed that inulin cannot unequivocally be described as a polydisperse 1-kestose-based (GFn) beta (2-->1) linear fructan chain, but that inulin always contains small amounts of Fm and branched molecules. This review article describes the presence of inulin and oligofructose in common foodstuffs. Historical data on human consumption add an extra dimension. Modern analytical techniques (HPLC, LGC, HPAEC-PAD) are used to check the variety of data mentioned in the literature throughout the past century. Methods to determine inulin and oligofructose in natural foodstuffs (cereals, fruit, and vegetables) are optimized and used to determine the loss of inulin during storage and during preparation of the food. These findings allow quantification of the amount of inulin and oligofructose in the average daily western diet. The daily per capita intake is estimated to range from 1 to 10 g, depending on geographic, demographic, and other related parameters (age, sex, season, etc.). Inulin and oligofructose are not measured by classic methods of dietary fiber analysis and consequently are often not mentioned in food tables. Their significant contribution (1 to 10 g/d/per capita) to the dietary fiber fraction (recommended at 25 g/d/per capita) is not taken into account in any nutritional recommendations. In view of this, inulin and oligofructose deserve more attention, both in food composition tables and in diet or nutrition studies.

Effects of the prebiotics inulin and lactulose on intestinal immunology and hematology of preruminant calves

“…Control groups were fed the pure replacer, and the other groups were fed the same milk replacer iso-energetically and iso-nitrogenically enriched with 2% (dry matter) of either inulin (Beneo ST, Orafti, Tienen, Belgium) or lactulose (Lactusat, Milei GmbH, Leutkirch, Germany). This concentration is approximately equivalent to suggestions on the consumption of dietary fiber in human diets (Van Loo et al, 1995). In a previous study, lactulose has been used in similar concentrations (Fleige et al, 2009).…”

“…Inulin is a natural b-(2-1)-linked fructo-oligosaccharide with up to 60 units common in plants used in the Western diet (Van Loo et al, 1995). It has been shown to lead to a shift in the intestinal bacterial flora toward more beneficial bifidobacteria , to impede carcinogenesis (Femia et al, 2002) or to stimulate the immune system (Schley and Field, 2002).…”

Oligofructose promotes satiety in healthy human: a pilot study

“…Food consumption was recorded daily during the period test (OFS and DM) by the subjects and analysed by our dietitian; a food frequency questionnaire and 24 h recall were recorded on the days before test meals to validate the self-daily food record. Reported energy, macronutrients and fibre intakes were calculated using the program Diet-Expert 2000, and fructans intake was calculated taking into account the content reported in food stuff by Van Loo et al (1995).…”

“…It is the case of dietary fructans, namely inulin-type fructans, which were recently recognized as dietary fibres Delzenne, 2003). They are commonly found in several vegetables and cereals (onion, garlic, wheat, etc) and in food products in which they are added for their nutritional or organoleptic properties (fat or sugar replacer) (Van Loo et al, 1995;Roberfroid and Delzenne, 1998). Animal studies suggest that dietary consumption of oligofructose (OFS) -a short-chain fructan obtained from inulinmight enhance satiety, thereby resulting in greater reductions in energy intake in normal, Zucker fa/fa rats and streptozotocin-treated diabetic rats (Daubioul et al, 2002;Cani et al, 2005a).…”

Altered gastrointestinal microbiota in irritable bowel syndrome and its modification by diet: probiotics, prebiotics and the low FODMAP diet

“…The compounds identified as having the most evidence for prebiotic effects are the inulin-type fructans (fructo-oligosaccharides, inulin, oligofructose) and galacto-oligosaccharides (GOS), many of which are widely distributed throughout the diet predominantly in grains, vegetables and pulses (88,89) . Total daily dietary intake of inulin and oligofructose in the UK and Europe in healthy individuals is 4 and 10 g/d, respectively (88)(89)(90) . Due to their indigestibility in the human small intestine, prebiotics become available for colonic bacterial fermentation.…”