Arabinoxylan, the major dietary fibre component of wheat bran, is important both from the technological and nutritional point of view. New enzymatic technologies were developed in the HEALTHGRAIN project to partly and selectively degrade arabinoxylan. The results offer potential for a new soluble fibre ingredient based on wheat bran.
The health benefits of cereal fibre, in particular in the prevention of lifestyle diseases such as diabetes, obesity, cardiovascular diseases, and cancer, are today generally recognized. Authoritative dietetic associations all around the world recommend consumption of cereal based products containing bran and fibre over products prepared from refined cereals. Arabinoxylan is the major dietary fibre component of both wheat and rye. It thus offers many possibilities for new ingredient manufacture.
Xylanase enzymes offer an efficient and specific tool to solubilise arabinoxylan polymers, and further to produce short-chain arabinoxylan oligosaccharides (AXOs). New xylanase enzymes were identified and characterized to have specific activities, and also to operate in the high temperature conditions during baking. One approach was to enzymatically solubilize AXOs in situ during the breadmaking process. An enzymatic process for AXOs production has already been developed (www.fugeia.be). Furthermore, extensive ball milling was shown to degrade arabinoxylans, offering tentative new possibilities for AXOs design.
A major feature of AXOs is that, in the colon, they are fermented to short chain fatty acids in general and butyric acid in particular. Butyric acid is important for the large intestinal mucosa cells. Arabinoxylan and AXOs are also known to be bifidogenic, ie they promote the growth of Bifidobacterium in the gut. The potential antioxidant power of AXOS deserves further studies.
The EU Integrated Project HEALTHGRAIN: The HEALTHGRAIN project has substantially strengthened the scientific basis for a new generation of cereal based products with enhanced health benefits. The project also has formed a network of research organizations, industries and organizations communicating to consumers that will continue as the HEALTHGRAIN Forum. It has been coordinated by Academy Professor Kaisa Poutanen from VTT Technical Research Centre of Finland. Results of the project will be presented in the HEALTHGRAIN Conference on May 5-7 in Lund, Sweden: www.healthgrain.org
Katholieke Universiteit Leuven: The KU Leuven carries out fundamental and applied research in all academic disciplines with a clear international orientation. Our annual research expenditures are around 230 million euro (exact sciences account for 44%, biomedical sciences for 30%, humanities for 19%, and interfacultary institutes for 7%); our scientific staff counts over 5,300 researchers, including 1,800 senior researchers, 10% are international scholars, up to 30% in the most advanced research domains. Applied research is supported by the well-experienced K.U.Leuven Research & Development, one of the most prominent technology transfer offices in Europe. For a short overview of main facts & figures: http://www.kuleuven.be/english/about.
Key references:
Swennen, K, Courtin, CM, Lindemans, GCJE, Delcour, JA, Large scale production and charac-terisation of wheat bran arabinoxylooligosaccharides, 2006, Journal of the Science of Food and Agriculture, 86, 1722-1731.
Eeckhaut, V, Van Immerseel, F, Dewulf, J, Pasmans, F, Haesebrouck, F, Ducatelle, R, Courtin, CM, Delcour, JA, Broekaert, WF, Arabinoxylooligosaccharides from wheat bran inhibit Salmonella colonization in broiler chickens, 2008, Poultry Science, 87, 2329-2334.
Courtin, CM, Swennen, K, Verjans, P, Delcour, JA, Stability of arabinoxylo-oligosaccharides, xylooligosaccharides and fructooligosaccharides, 2009, Food Chemistry, 112, 831-837.
Further information:
Jan A. Delcour or Christophe M. Courtin, Katholieke Universiteit Leuven
Kasteelpark Arenberg 20, 3001 Heverlee, Belgium
Email: jan.delcour@biw.kuleuven.be; christophe.courtin@biw.kuleuven.be,
Phone: +32 16 321634; Fax: +32 16 321997