Prof. Jan Delcour
Food Science Department and Nutrition Research Centre, Leuven Belgium
From wheat bran to ArabinoXylan OligoSaccharides: production, demonstration of prebiotic effects and regulatory aspects
Prebiotics are selectively fermented ingredients that allow specific changes, both in the composition and/or activity of the gastrointestinal microflora, that confer benefits upon host well-being and health. The most studied prebiotics are the fructans inulin and fructo-oligosaccharides. This presentation deals with the multidisciplinary effort which was undertaken to study the properties of arabinoxylan oligosaccharides (AXOS) as novel prebiotics. The work included the development of a pilot scale enzymatic process for extracting AXOS from wheat bran, a milling co-product rich in the dietary fibre arabinoxylan. Studies of their prebiotic effects in chickens and rats as well as in humans were also executed. A major feature of AXOS is that, in the colon, it is selectively fermented to short chain fatty acids in general and butyric acid (a fuel for colon mucosa cells) in particular. AXOS induces specific changes, both in the composition and/or activity of the gastrointestinal microflora, that confer benefits upon host well-being and health. It thus meets the criteria needed for classification as prebiotics. However, EFSA does not allow health claims which are based on changes in the gastro-intestinal microflora.