One hundred percent of distiller's dried grains with solubles (DDGS) can be pelletized without adding a binding agent or anything else, according to US Agricultural Research Service (ARS) scientists.
ARS agricultural engineer Kurt Rosentrater has turned DDGS from corn-based ethanol production into high-quality pellets using processing equipment at a commercial feed mill. The heating used in pelletizing did not harm the high-protein, low-starch nutrient content. Rosentrater's work has been developed at the ARS North Central Agricultural Research Laboratory, in South Dakota, where he works with colleagues at ARS and at nearby South Dakota State University.
Cattle feed is currently the primary outlet for distiller's grain. But other livestock such as swine and poultry can also eat it. To date, there are no commercial DDGS pellets available for livestock, which limits the byproduct’s use in rangeland settings.
Fish raised for food in the growing aquaculture industry eat pelletized feed, but those pellets contain commercial fish meal as a protein source, not the less-expensive distiller's grain. Rosentrater is experimenting with adding soy and corn flour to distiller's grain to produce pelletized feeds, to see how far he can reduce the fish meal—or if he can eliminate it entirely.
This pelletizing work also promises to solve a growing problem of product deterioration—as well as hardening and caking problems during shipping and storage, which can clog the various chutes and bins that DDGS flows through. With an increasing supply of the byproduct, ethanol plants have to ship it greater distances to reach markets.