Pellet Quality of Corn-Based DDGS

The rapid growth of corn-based dry grind ethanol plants over the past decade in the US has resulted in a great increase in production of the coproduct DDGS (distillers dried grains with solubles). Since some physical properties like low bulk density and poor flowability can impact the market potential of DDGS, pelleting of DDGS can be one of the easiest ways to improve this situation. Pellet quality is the focus of this project. The pelleting process was conducted with three initial DDGS moisture contents and two different dies; a total of six runs were completed to produce DDGS pellets. The physical qualities of pelleted DDGS were determined by measuring durability, bulk density, angle of repose, and color of the pellets. The results showed that the durability ranged from 42% to 89%, the highest pellet durability occurred when the moisture content was 20% db and the die diameter was 1/8 in. The bulk density increased when the DDGS moisture content decreased, and the highest bulk density was observed when the moisture content was 10% db and the die diameter was 1/8 in.