International Dietary Fibre Conference (DF12) location:Rome, Italy date:7 - 9 May 2012
The modern consumer is aware of the link between food consumption and health. Therefore, the demand for functional foods, i.e. foods with health-promoting or disease-preventing characteristics, increases. Examples of functional foods are foods fortified with dietary fibre, probiotics, prebiotics, antioxidants and/or vitamins. Health effects of food containing a significant content of dietary fibre are not only assigned to the dietary fibre fraction, but also to associated antioxidants, vitamins and minerals. Previous research showed that dietary fibre compounds named arabinoxylan-oligosaccharides (AXOS), hydrolysis products of arabinoxylan, have prebiotic properties. Although AXOS molecules can carry ester-linked ferulic acid, a powerful antioxidant, the antioxidant capacity of AXOS preparations has been examined much less. To evaluate the antioxidant capacity and structure-function relationship of AXOS, ferulic acid enriched AXOS (f-AXOS) were obtained by use of Amberlite XAD-4 and successive elution with ethanol-water mixtures and ferulic acid depleted AXOS were obtained through treatment with ferulic acid esterase. Carbohydrate content and composition and ferulic acid content of f-AXOS and AXOS samples were determined. The antioxidant capacity of these fractions was determined by use of a Trolox equivalent antioxidant capacity (TEAC) assay. As AXOS are water soluble dietary fibre compounds, and possibly combine prebiotic and antioxidant activities, they are interesting compounds for incorporation in many functional foods, including AXOS enriched bread.