Effect of Debranning and Process Temperature on the Production of Bioethanol and Distillers’ Dried Grain with Solubles from Triticale

Very high gravity (VHG) starch to ethanol fermentation with whole and debranned triticale grains using the conventional (warm) and cold (raw starch) conversion methods were compared, with regards to fermentation performance and the quality of the distillers’ dried grains with solubles (DDGS). For both the warm and cold process configurations, debranning increased final ethanol concentration, yield (as % of theoretical maximum) and productivity. Furthermore, debranning decreased the required enzyme dosage of the cold process by 20.7%. The improvements by debranning were achieved by nutrient-recycling from the protease-treated bran and germ hydrolysate to the fermentation slurries of these processes. DDGS produced by the cold debranned process configuration had the highest protein content of 44%, while the neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of 17.8% and 13.8%, respectively, were lower than DDGS from the whole grain, making it the more favourable animal feed ingredient, particularly for monogastric animals.