Submitted to: BioResources
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/2/2012
Publication Date: 5/25/2012
Citation: Samala, A., Srinivasan, R., Yadav, M.P., Kim, T., Prewitt, L. 2012. Xylo-oligosaccharides production by autohydrolysis of corn fiber separated from DDGS. BioResources. 7(3):3038-3050. Interpretive Summary: In dry grind corn processing, ethanol is produced from the starch portion of the kernel and the remaining material is dried to produce distillers dried grains with solubles (DDGS). This relatively low value material is the only coproduct (other than carbon dioxide) and has a limited number of uses. In order to generate new value added coproducts and improve the economics of ethanol production, xylo-oligosaccharides (XOS) were produced from corn fiber separated from DDGS. For XOS production, a simple heating process in a closed vessel was used, which does not require any chemical treatment. It is very economical and takes a short time to complete the whole auto hydrolysis process. XOS are reported to have beneficial health properties and considered to be functional food ingredients. They are low in digestible sugars and are utilized as a "prebiotic", a compound used to stimulate the growth and activity of beneficial bacteria in the colon. This finding will be useful to commercial manufacturers who are trying to develop a new commercial product based upon fiber separated from DDGS. If successful, it will lead to new markets for DDGS, which will benefit U.S. corn processors and corn growers. The generation and recovery of additional valuable product from corn dry milling by-products will also indirectly help to reduce overall cost of fuel ethanol produced from corn kernels.
Technical Abstract: Xylo-oligosaccharides (XOS) are reported to have beneficial health properties, and are considered to be functional food ingredients. XOS was produced using corn fiber separated from distillers dried grains with solubles (DDGS). Corn fiber was treated with deionized water in a Parr-reactor, at temperatures ranging from 140 to 220 deg C to produce XOS by autohydrolysis and to determine the optimum temperature for XOS production. The reaction was conducted with 10 grams of corn fiber in 90 mL of deionized water. The holding time after desired temperature reached was 15 min. The maximum total yield of XOS in the solution was 17.9 to 18.6 wt% of the corn fiber at 170-180 deg C. There were no traces of formic acid and levulinic acid. This study showed that XOS can be produced from corn fiber, which may provide health benefits, including prebiotic and antioxidant activities.