Nutritional composition, nitrogen-corrected true metabolizable energy, and amino acid digestibilities of new corn distillers dried grains with solubles produced by new fractionation processes

As ethanol production is increasing, new processes are being developed to maximize ethanol production from corn and to create new, more highly marketable corn distillers dried grains with or without solubles (DDGS or DDG, respectively). This current study evaluated coproducts produced from 2 new modified processes, the enzymatic milling (E-Mill) and the Elusieve process. The E-Mill process subjects the corn kernel to enzymes that hydrolyze starch and help in removing germ, pericarp, and endosperm fiber to create a modified higher protein, lower fiber DDG. The Elusieve process involves sieving the finished co-product, DDGS, and then elutriating (air classifying) to remove fiber from the DDGS samples. A precision-fed cecectomized rooster assay was conducted to determine TME_n and amino acid digestibilities of E-Mill DDG and several Elusieve DDGS samples produced using different screen sizes and elutriation air velocities. When compared with a conventionally processed DDGS, E-Mill DDG had increased protein (56.4 vs. 29.9%), increased TME_n (3.656 vs. 3.299 kcal/g of DM), and higher amino acid digestibilities. When DDGS was subjected to various Elusieve processes, the resulting DDGS samples generally had an increased protein content and TME_n. As expected, the higher fiber fractions obtained from the Elusieve process had reduced protein, amino acid concentrations, amino acid digestibilities, and TME_n in comparison to the lower fiber fractions produced from the Elusieve process. The results of this study indicate that the Elusieve and E-Mill processes can be used to increase the nutritional value of DDGS for poultry.