ARS | Publication request: DDGs for Horticultural Applications

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 18, 2008
Publication Date: July 18, 2008
Citation: Vaughn, S.F. 2008. DDGs for horticultural applications. Meeting Abstract. 21.

Technical Abstract: Ethanol production using corn as the primary feedstock is rapidly expanding in the U.S. (>125% in the past four years) and, by 2012, production is estimated to reach 12 billion gallons. Corn is prepared for ethanol fermentation by either wet or dry milling. Due to the lower capital costs of dry milling plants, plants currently under construction in the U.S. cornbelt are of this type. In the conventional dry milling process, whole corn is ground and mixed with water to produce a slurry, which is subsequently cooked, liquified, saccharified, and fermented to produce ethanol. The remaining non-fermentables (germ, fiber) are recovered as a co-product termed dried distiller's grains (DDGs), which are used almost exclusively as animal feed. We have shown, through our research, that DDGs can be used for several horticultural applications, including as a soil amendment/organic fertilizer for high-value crops such as turfgrasses and tomatoes. In addition, we have found that valuable co-products, such as corn oil (for biodiesel production) and phytosterols (for food uses), can be removed by solvent extraction without affecting the horticultural properties of the DDGs. An additional positive result of the solvent extraction process is that the characteristic odor of the DDGs (a negative when applied as a fertilizer) is reduced substantially by solvent extraction. As the price of DDGs as animal feed is typically less than $100/ton, finding higher-value markets for DDGs could potentially create new products for these alternative uses as well as increased income for the ethanol industry.